queryparser/queryparser_internal.cc

Go to the documentation of this file.

/* Driver template for the LEMON parser generator.
** The author disclaims copyright to this source code.
*/
/* First off, code is included which follows the "include" declaration
** in the input file. */
#line 1 "queryparser/queryparser.lemony"

/* queryparser.lemony: build a Xapian::Query object from a user query string.
 *
 * Copyright (C) 2004,2005,2006,2007,2008,2009,2010 Olly Betts
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
 * USA
 */

#include <config.h>

#include "omassert.h"
#include "queryparser_internal.h"
#include <xapian/error.h>
#include <xapian/unicode.h>
#include "stringutils.h"

// Include the list of token values lemon generates.
#include "queryparser_token.h"

#include <algorithm>
#include <list>
#include <string>

#include <string.h>

using namespace std;

using namespace Xapian;

inline bool
U_isupper(unsigned ch) {
    return (ch < 128 && C_isupper((unsigned char)ch));
}

inline bool
U_isdigit(unsigned ch) {
    return (ch < 128 && C_isdigit((unsigned char)ch));
}

inline bool
U_isalpha(unsigned ch) {
    return (ch < 128 && C_isalpha((unsigned char)ch));
}

using Xapian::Unicode::is_whitespace;

inline bool
is_not_whitespace(unsigned ch) {
    return !is_whitespace(ch);
}

using Xapian::Unicode::is_wordchar;

inline bool
is_not_wordchar(unsigned ch) {
    return !is_wordchar(ch);
}

inline bool
is_digit(unsigned ch) {
    return (Unicode::get_category(ch) == Unicode::DECIMAL_DIGIT_NUMBER);
}

// FIXME: we used to keep trailing "-" (e.g. Cl-) but it's of dubious utility
// and there's the risk of hyphens getting stuck onto the end of terms...
inline bool
is_suffix(unsigned ch) {
    return ch == '+' || ch == '#';
}

inline bool
prefix_needs_colon(const string & prefix, unsigned ch)
{
    if (!U_isupper(ch)) return false;
    string::size_type len = prefix.length();
    return (len > 1 && prefix[len - 1] != ':');
}

using Unicode::is_currency;

struct filter_group_id {
    list<string> prefixes;

    Xapian::valueno valno;

    explicit filter_group_id(const list<string> & prefixes_)
        : prefixes(prefixes_), valno(Xapian::BAD_VALUENO) {}

    explicit filter_group_id(Xapian::valueno valno_)
        : prefixes(), valno(valno_) {}

    bool operator<(const filter_group_id & other) const {
        if (prefixes != other.prefixes) {
            return prefixes < other.prefixes;
        }
        return valno < other.valno;
    }
};

class Term {
    State * state;

  public:
    string name;
    list<string> prefixes;
    string unstemmed;
    QueryParser::stem_strategy stem;
    termpos pos;

    Term(const string &name_, termpos pos_) : name(name_), stem(QueryParser::STEM_NONE), pos(pos_) { }
    Term(const string &name_) : name(name_), stem(QueryParser::STEM_NONE), pos(0) { }
    Term(const string &name_, const list<string> &prefixes_)
        : name(name_), prefixes(prefixes_), stem(QueryParser::STEM_NONE), pos(0) { }
    Term(termpos pos_) : stem(QueryParser::STEM_NONE), pos(pos_) { }
    Term(State * state_, const string &name_, const list<string> &prefixes_,
         const string &unstemmed_,
         QueryParser::stem_strategy stem_ = QueryParser::STEM_NONE,
         termpos pos_ = 0)
        : state(state_), name(name_), prefixes(prefixes_), unstemmed(unstemmed_),
          stem(stem_), pos(pos_) { }

    string make_term(const string & prefix) const;

    void need_positions() {
        if (stem == QueryParser::STEM_SOME) stem = QueryParser::STEM_NONE;
    }

    termpos get_termpos() const { return pos; }

    filter_group_id get_filter_group_id() const { return filter_group_id(prefixes); }

    Query * as_wildcarded_query(State * state) const;

    Query * as_partial_query(State * state_) const;

    Query get_query() const;

    Query get_query_with_synonyms() const;

    Query get_query_with_auto_synonyms() const;
};

class State {
    QueryParser::Internal * qpi;

  public:
    Query query;
    const char * error;
    unsigned flags;

    State(QueryParser::Internal * qpi_, unsigned flags_)
        : qpi(qpi_), error(NULL), flags(flags_) { }

    string stem_term(const string &term) {
        return qpi->stemmer(term);
    }

    void add_to_stoplist(const Term * term) {
        qpi->stoplist.push_back(term->name);
    }

    void add_to_unstem(const string & term, const string & unstemmed) {
        qpi->unstem.insert(make_pair(term, unstemmed));
    }

    valueno value_range(Query & q, Term *a, Term *b) {
        list<ValueRangeProcessor *>::const_iterator i;
        for (i = qpi->valrangeprocs.begin(); i != qpi->valrangeprocs.end(); ++i) {
            string start = a->name;
            string end = b->name;
            Xapian::valueno valno = (**i)(start, end);
            if (valno != Xapian::BAD_VALUENO) {
                delete a;
                delete b;
                q = Query(Query::OP_VALUE_RANGE, valno, start, end);
                return valno;
            }
        }
        // FIXME: Do we want to report an error for this?  If not we need
        // to perform the above check in the tokeniser and if none of the
        // ValueRangeProcessor classes like the range, we rollback to
        // parsing the query without treating this as a range.  Needs
        // more thought and probably a look at queries users actually
        // enter.
        error = "Unknown range operation";
        return Xapian::BAD_VALUENO;
    }

    Query::op default_op() const { return qpi->default_op; }

    bool is_stopword(const Term *term) const {
        return qpi->stopper && (*qpi->stopper)(term->name);
    }

    Database get_database() const {
        return qpi->db;
    }
};

string
Term::make_term(const string & prefix) const
{
    string term;
    if (stem == QueryParser::STEM_SOME) term += 'Z';
    if (!prefix.empty()) {
        term += prefix;
        if (prefix_needs_colon(prefix, name[0])) term += ':';
    }
    if (stem != QueryParser::STEM_NONE) {
        term += state->stem_term(name);
    } else {
        term += name;
    }

    if (!unstemmed.empty())
        state->add_to_unstem(term, unstemmed);
    return term;
}

Query
Term::get_query_with_synonyms() const
{
    Query q = get_query();

    // Handle single-word synonyms with each prefix.
    list<string>::const_iterator piter;
    for (piter = prefixes.begin(); piter != prefixes.end(); ++piter) {
        // First try the unstemmed term:
        string term;
        if (!piter->empty()) {
            term += *piter;
            if (prefix_needs_colon(*piter, name[0])) term += ':';
        }
        term += name;

        Xapian::Database db = state->get_database();
        Xapian::TermIterator syn = db.synonyms_begin(term);
        Xapian::TermIterator end = db.synonyms_end(term);
        if (syn == end && stem != QueryParser::STEM_NONE) {
            // If that has no synonyms, try the stemmed form:
            term = 'Z';
            if (!piter->empty()) {
                term += *piter;
                if (prefix_needs_colon(*piter, name[0])) term += ':';
            }
            term += state->stem_term(name);
            syn = db.synonyms_begin(term);
            end = db.synonyms_end(term);
        }
        while (syn != end) {
            q = Query(Query::OP_OR, q, Query(*syn, 1, pos));
            ++syn;
        }
    }
    return q;
}

Query
Term::get_query_with_auto_synonyms() const
{
    if (state->flags & QueryParser::FLAG_AUTO_SYNONYMS)
        return get_query_with_synonyms();

    return get_query();
}

static void
add_to_query(Query *& q, Query::op op, Query * term)
{
    Assert(term);
    if (q) {
        *q = Query(op, *q, *term);
        delete term;
    } else {
        q = term;
    }
}

static void
add_to_query(Query *& q, Query::op op, const Query & term)
{
    if (q) {
        *q = Query(op, *q, term);
    } else {
        q = new Query(term);
    }
}

Query
Term::get_query() const
{
    Assert(prefixes.size() >= 1);
    list<string>::const_iterator piter = prefixes.begin();
    Query q(make_term(*piter), 1, pos);
    while (++piter != prefixes.end()) {
        q = Query(Query::OP_OR, q, Query(make_term(*piter), 1, pos));
    }
    return q;
}

Query *
Term::as_wildcarded_query(State * state_) const
{
    Database db = state_->get_database();
    vector<Query> subqs;
    list<string>::const_iterator piter;
    for (piter = prefixes.begin(); piter != prefixes.end(); ++piter) {
        string root = *piter;
        root += name;
        TermIterator t = db.allterms_begin(root);
        while (t != db.allterms_end(root)) {
            subqs.push_back(Query(*t, 1, pos));
            ++t;
        }
    }
    delete this;
    return new Query(Query::OP_OR, subqs.begin(), subqs.end());
}

Query *
Term::as_partial_query(State * state_) const
{
    Database db = state_->get_database();
    vector<Query> subqs;
    list<string>::const_iterator piter;
    for (piter = prefixes.begin(); piter != prefixes.end(); ++piter) {
        string root = *piter;
        root += name;
        TermIterator t = db.allterms_begin(root);
        while (t != db.allterms_end(root)) {
            subqs.push_back(Query(*t, 1, pos));
            ++t;
        }
        // Add the term, as it would normally be handled, as an alternative.
        subqs.push_back(Query(make_term(*piter), 1, pos));
    }
    delete this;
    return new Query(Query::OP_OR, subqs.begin(), subqs.end());
}

inline bool
is_phrase_generator(unsigned ch)
{
    // These characters generate a phrase search.
    if (rare(ch == 0)) return false;
    if (ch < 128) {
        // Ordered mostly by frequency of calls to this function done when
        // running queryparsertest.
        return (strchr(".-/:\\@", ch) != NULL);
    }
    switch (Unicode::get_category(ch)) {
        case Xapian::Unicode::NON_SPACING_MARK:
        case Xapian::Unicode::ENCLOSING_MARK:
        case Xapian::Unicode::COMBINING_SPACING_MARK:
            return true;
        case Xapian::Unicode::FORMAT:
            return (ch >= 0x200b &&
                    (ch <= 0x200d || ch == 0x2060 || ch == 0xfeff));
        default:
            return false;
    }
}

inline bool
is_stem_preventer(unsigned ch)
{
    return (ch && ch < 128 && strchr("(/\\@<>=*[{\"", ch) != NULL);
}

inline bool
should_stem(const string & term)
{
    const unsigned int SHOULD_STEM_MASK =
        (1 << Unicode::LOWERCASE_LETTER) |
        (1 << Unicode::TITLECASE_LETTER) |
        (1 << Unicode::MODIFIER_LETTER) |
        (1 << Unicode::OTHER_LETTER);
    Utf8Iterator u(term);
    return ((SHOULD_STEM_MASK >> Unicode::get_category(*u)) & 1);
}

inline unsigned check_infix(unsigned ch) {
    if (ch == '\'' || ch == '&' || ch == 0xb7 || ch == 0x5f4 || ch == 0x2027) {
        // Unicode includes all these except '&' in its word boundary rules,
        // as well as 0x2019 (which we handle below) and ':' (for Swedish
        // apparently, but we ignore this for now as it's problematic in
        // real world cases).
        return ch;
    }
    // 0x2019 is Unicode apostrophe and single closing quote.
    // 0x201b is Unicode single opening quote with the tail rising.
    if (ch == 0x2019 || ch == 0x201b) return '\'';
    return 0;
}

inline unsigned check_infix_digit(unsigned ch) {
    // This list of characters comes from Unicode's word identifying algorithm.
    switch (ch) {
        case ',':
        case '.':
        case ';':
        case 0x037e: // GREEK QUESTION MARK
        case 0x0589: // ARMENIAN FULL STOP
        case 0x060D: // ARABIC DATE SEPARATOR
        case 0x07F8: // NKO COMMA
        case 0x2044: // FRACTION SLASH
        case 0xFE10: // PRESENTATION FORM FOR VERTICAL COMMA
        case 0xFE13: // PRESENTATION FORM FOR VERTICAL COLON
        case 0xFE14: // PRESENTATION FORM FOR VERTICAL SEMICOLON
            return ch;
    }
    return 0;
}

struct yyParser;

// Prototype the functions lemon generates.
static yyParser *ParseAlloc();
static void ParseFree(yyParser *);
static void Parse(yyParser *, int, Term *, State *);

void
QueryParser::Internal::add_prefix(const string &field, const string &prefix,
                                  bool filter)
{
    map<string, PrefixInfo>::iterator p = prefixmap.find(field);
    if (p == prefixmap.end()) {
       prefixmap.insert(make_pair(field, PrefixInfo(filter, prefix)));
    } else {
       // Check that this is the same type of filter as the existing one(s).
       if (p->second.filter != filter) {
           throw Xapian::InvalidOperationError("Can't use add_prefix() and add_bool_prefix() on the same field name");
       }
       p->second.prefixes.push_back(prefix);
    }
}

string
QueryParser::Internal::parse_term(Utf8Iterator &it, const Utf8Iterator &end,
                                  bool &was_acronym)
{
    string term;
    // Look for initials separated by '.' (e.g. P.T.O., U.N.C.L.E).
    // Don't worry if there's a trailing '.' or not.
    if (U_isupper(*it)) {
        string t;
        Utf8Iterator p = it;
        do {
            Unicode::append_utf8(t, *p++);
        } while (p != end && *p == '.' && ++p != end && U_isupper(*p));
        // One letter does not make an acronym!  If we handled a single
        // uppercase letter here, we wouldn't catch M&S below.
        if (t.length() > 1) {
            // Check there's not a (lower case) letter or digit
            // immediately after it.
            // FIXME: should I.B.M..P.T.O be a range search?
            if (p == end || !is_wordchar(*p)) {
                it = p;
                swap(term, t);
            }
        }
    }
    was_acronym = !term.empty();

    if (term.empty()) {
        unsigned prevch = *it;
        Unicode::append_utf8(term, prevch);
        while (++it != end) {
            unsigned ch = *it;
            if (!is_wordchar(ch)) {
                // Treat a single embedded '&' or "'" or similar as a word
                // character (e.g. AT&T, Fred's).  Also, normalise
                // apostrophes to ASCII apostrophe.
                Utf8Iterator p = it;
                ++p;
                if (p == end || !is_wordchar(*p)) break;
                unsigned nextch = *p;
                if (is_digit(prevch) &&
                    is_digit(nextch)) {
                    ch = check_infix_digit(ch);
                } else {
                    ch = check_infix(ch);
                }
                if (!ch) break;
            }
            Unicode::append_utf8(term, ch);
            prevch = ch;
        }
        if (it != end && is_suffix(*it)) {
            string suff_term = term;
            Utf8Iterator p = it;
            // Keep trailing + (e.g. C++, Na+) or # (e.g. C#).
            do {
                if (suff_term.size() - term.size() == 3) {
                    suff_term.resize(0);
                    break;
                }
                suff_term += *p;
            } while (is_suffix(*++p));
            if (!suff_term.empty() && (p == end || !is_wordchar(*p))) {
                // If the suffixed term doesn't exist, check that the
                // non-suffixed term does.  This also takes care of
                // the case when QueryParser::set_database() hasn't
                // been called.
                bool use_suff_term = false;
                string lc = Unicode::tolower(suff_term);
                if (db.term_exists(lc)) {
                    use_suff_term = true;
                } else {
                    lc = Unicode::tolower(term);
                    if (!db.term_exists(lc)) use_suff_term = true;
                }
                if (use_suff_term) {
                    term = suff_term;
                    it = p;
                }
            }
        }
    }
    return term;
}

class ParserHandler {
    yyParser * parser;

  public:
    explicit ParserHandler(yyParser * parser_) : parser(parser_) { }
    operator yyParser*() { return parser; }
    ~ParserHandler() { ParseFree(parser); }
};

Query
QueryParser::Internal::parse_query(const string &qs, unsigned flags,
                                   const string &default_prefix)
{
    // Set value_ranges if we may have to handle value ranges in the query.
    bool value_ranges;
    value_ranges = !valrangeprocs.empty() && (qs.find("..") != string::npos);

    termpos term_pos = 1;
    Utf8Iterator it(qs), end;

    State state(this, flags);

    // To successfully apply more than one spelling correction to a query
    // string, we must keep track of the offset due to previous corrections.
    int correction_offset = 0;
    corrected_query.resize(0);

    // Stack of prefixes, used for phrases and subexpressions.
    list<const PrefixInfo *> prefix_stack;

    // If default_prefix is specified, use it.  Otherwise, use any list
    // that has been set for the empty prefix.
    const PrefixInfo def_pfx(false, default_prefix);
    {
        const PrefixInfo * default_prefixinfo = &def_pfx;
        if (default_prefix.empty()) {
            map<string, PrefixInfo>::const_iterator f = prefixmap.find("");
            if (f != prefixmap.end()) default_prefixinfo = &(f->second);
        }

        // We always have the current prefix on the top of the stack.
        prefix_stack.push_back(default_prefixinfo);
    }

    ParserHandler pParser(ParseAlloc());

    unsigned newprev = ' ';
main_lex_loop:
    enum {
        DEFAULT, IN_QUOTES, IN_PREFIXED_QUOTES, IN_PHRASED_TERM, IN_GROUP,
        EXPLICIT_SYNONYM
    } mode = DEFAULT;
    while (it != end && !state.error) {
        bool last_was_operator = false;
        if (mode == EXPLICIT_SYNONYM) mode = DEFAULT;
        if (false) {
just_had_operator:
            if (it == end) break;
            mode = DEFAULT;
just_had_synonym_operator:
            last_was_operator = true;
        }
        if (mode == IN_PHRASED_TERM) mode = DEFAULT;
        if (is_whitespace(*it)) {
            newprev = ' ';
            ++it;
            it = find_if(it, end, is_not_whitespace);
            if (it == end) break;
        }

        if ((mode == DEFAULT || mode == IN_GROUP) && value_ranges) {
            // Scan forward to see if this could be the "start of range"
            // token.  Sadly this has O(n^2) tendencies, though at least
            // "n" is the number of words in a query which is likely to
            // remain fairly small.  FIXME: can we tokenise more elegantly?
            Utf8Iterator p = it;
            unsigned ch = 0;
            while (p != end) {
                if (ch == '.' && *p == '.') {
                    ++p;
                    if (p == end || *p <= ' ' || *p == ')') break;

                    string r;
                    do {
                        Unicode::append_utf8(r, *it++);
                    } while (it != p);
                    // Trim off the trailing "..".
                    r.resize(r.size() - 2);
                    Parse(pParser, RANGE_START, new Term(r), &state);
                    r.resize(0);
                    // Allow any character except whitespace and ')' in a
                    // RANGE_END.  Or should we be consistent with RANGE_START?
                    do {
                        Unicode::append_utf8(r, *p++);
                    } while (p != end && *p > ' ' && *p != ')');
                    Parse(pParser, RANGE_END, new Term(r), &state);
                    it = p;
                    goto main_lex_loop;
                }
                ch = *p;
                if (!(is_wordchar(ch) || is_currency(ch) ||
                      (ch < 128 && strchr("%,-./:@", ch)))) break;
                ++p;
            }
        }

        if (!is_wordchar(*it)) {
            unsigned prev = newprev;
            unsigned ch = *it++;
            newprev = ch;
            // Drop out of IN_GROUP mode.
            if (mode == IN_GROUP) mode = DEFAULT;
            switch (ch) {
              case '"': // Quoted phrase.
                if (mode == DEFAULT) {
                    // Skip whitespace.
                    it = find_if(it, end, is_not_whitespace);
                    if (it == end) {
                        // Ignore an unmatched " at the end of the query to
                        // avoid generating an empty pair of QUOTEs which will
                        // cause a parse error.
                        goto done;
                    }
                    if (*it == '"') {
                        // Ignore empty "" (but only if we're not already
                        // IN_QUOTES as we don't merge two adjacent quoted
                        // phrases!)
                        newprev = *it++;
                        break;
                    }
                }
                if (flags & QueryParser::FLAG_PHRASE) {
                    Parse(pParser, QUOTE, NULL, &state);
                    if (mode == DEFAULT) {
                        mode = IN_QUOTES;
                    } else {
                        // Remove the prefix we pushed for this phrase.
                        if (mode == IN_PREFIXED_QUOTES)
                            prefix_stack.pop_back();
                        mode = DEFAULT;
                    }
                }
                break;

              case '+': case '-': // Loved or hated term/phrase/subexpression.
                // Ignore + or - at the end of the query string.
                if (it == end) goto done;
                if (prev > ' ' && prev != '(') {
                    // Or if not after whitespace or an open bracket.
                    break;
                }
                if (is_whitespace(*it) || *it == '+' || *it == '-') {
                    // Ignore + or - followed by a space, or further + or -.
                    // Postfix + (such as in C++ and H+) is handled as part of
                    // the term lexing code in parse_term().
                    newprev = *it++;
                    break;
                }
                if (mode == DEFAULT && (flags & FLAG_LOVEHATE)) {
                    int token;
                    if (ch == '+') {
                        token = LOVE;
                    } else if (last_was_operator) {
                        token = HATE_AFTER_AND;
                    } else {
                        token = HATE;
                    }
                    Parse(pParser, token, NULL, &state);
                    goto just_had_operator;
                }
                // Need to prevent the term after a LOVE or HATE starting a
                // term group...
                break;

              case '(': // Bracketed subexpression.
                // Skip whitespace.
                it = find_if(it, end, is_not_whitespace);
                // Ignore ( at the end of the query string.
                if (it == end) goto done;
                if (prev > ' ' && strchr("()+-", prev) == NULL) {
                    // Or if not after whitespace or a bracket or '+' or '-'.
                    break;
                }
                if (*it == ')') {
                    // Ignore empty ().
                    newprev = *it++;
                    break;
                }
                if (mode == DEFAULT && (flags & FLAG_BOOLEAN)) {
                    prefix_stack.push_back(prefix_stack.back());
                    Parse(pParser, BRA, NULL, &state);
                }
                break;

              case ')': // End of bracketed subexpression.
                if (mode == DEFAULT && (flags & FLAG_BOOLEAN)) {
                    // Remove the prefix we pushed for the corresponding BRA.
                    // If brackets are unmatched, it's a syntax error, but
                    // that's no excuse to SEGV!
                    if (prefix_stack.size() > 1) prefix_stack.pop_back();
                    Parse(pParser, KET, NULL, &state);
                }
                break;

              case '~': // Synonym expansion.
                // Ignore at the end of the query string.
                if (it == end) goto done;
                if (mode == DEFAULT && (flags & FLAG_SYNONYM)) {
                    if (prev > ' ' && strchr("+-(", prev) == NULL) {
                        // Or if not after whitespace, +, -, or an open bracket.
                        break;
                    }
                    if (!is_wordchar(*it)) {
                        // Ignore if not followed by a word character.
                        break;
                    }
                    Parse(pParser, SYNONYM, NULL, &state);
                    mode = EXPLICIT_SYNONYM;
                    goto just_had_synonym_operator;
                }
                break;
            }
            // Skip any other characters.
            continue;
        }

        Assert(is_wordchar(*it));

        size_t term_start_index = it.raw() - qs.data();

        newprev = 'A'; // Any letter will do...

        // A term, a prefix, or a boolean operator.
        const PrefixInfo * prefixinfo = NULL;
        if ((mode == DEFAULT || mode == IN_GROUP || mode == EXPLICIT_SYNONYM) &&
            !prefixmap.empty()) {
            // Check for a fieldname prefix (e.g. title:historical).
            Utf8Iterator p = find_if(it, end, is_not_wordchar);
            if (p != end && *p == ':' && ++p != end && *p > ' ' && *p != ')') {
                string field;
                p = it;
                while (*p != ':')
                    Unicode::append_utf8(field, *p++);
                map<string, PrefixInfo>::const_iterator f;
                f = prefixmap.find(field);
                if (f != prefixmap.end()) {
                    // Special handling for prefixed fields, depending on the
                    // type of the prefix.
                    unsigned ch = *++p;
                    prefixinfo = &(f->second);

                    if (prefixinfo->filter) {
                        // Drop out of IN_GROUP if we're in it.
                        if (mode == IN_GROUP)
                            mode = DEFAULT;
                        it = p;
                        string name;
                        if (it != end && *it == '"') {
                            // Quoted boolean term (can contain any character).
                            ++it;
                            while (it != end) {
                                if (*it == '"') {
                                    // Interpret "" as an escaped ".
                                    if (++it == end || *it != '"')
                                        break;
                                }
                                Unicode::append_utf8(name, *it++);
                            }
                        } else {
                            // Can't boolean filter prefix a subexpression, so
                            // just use anything following the prefix until the
                            // next space or ')' as part of the boolean filter
                            // term.
                            while (it != end && *it > ' ' && *it != ')')
                                Unicode::append_utf8(name, *it++);
                        }
                        // Build the unstemmed form in field.
                        field += ':';
                        field += name;
                        const list<string> & prefixes = prefixinfo->prefixes;
                        Term * token = new Term(&state, name, prefixes, field);
                        Parse(pParser, BOOLEAN_FILTER, token, &state);
                        continue;
                    }

                    if (ch == '"' && (flags & FLAG_PHRASE)) {
                        // Prefixed phrase, e.g.: subject:"space flight"
                        mode = IN_PREFIXED_QUOTES;
                        Parse(pParser, QUOTE, NULL, &state);
                        it = p;
                        newprev = ch;
                        ++it;
                        prefix_stack.push_back(prefixinfo);
                        continue;
                    }

                    if (ch == '(' && (flags & FLAG_BOOLEAN)) {
                        // Prefixed subexpression, e.g.: title:(fast NEAR food)
                        mode = DEFAULT;
                        Parse(pParser, BRA, NULL, &state);
                        it = p;
                        newprev = ch;
                        ++it;
                        prefix_stack.push_back(prefixinfo);
                        continue;
                    }

                    if (is_wordchar(ch)) {
                        // Prefixed term.
                        it = p;
                    } else {
                        // It looks like a prefix but isn't, so parse it as
                        // text instead.
                        prefixinfo = NULL;
                    }
                }
            }
        }

phrased_term:
        bool was_acronym;
        string term = parse_term(it, end, was_acronym);

        // Boolean operators.
        if ((mode == DEFAULT || mode == IN_GROUP) &&
            (flags & FLAG_BOOLEAN) &&
            // Don't want to interpret A.N.D. as an AND operator.
            !was_acronym &&
            !prefixinfo &&
            term.size() >= 2 && term.size() <= 4 && U_isalpha(term[0])) {

            string op = term;
            if (flags & FLAG_BOOLEAN_ANY_CASE) {
                for (string::iterator i = op.begin(); i != op.end(); ++i) {
                    *i = C_toupper(*i);
                }
            }
            if (op.size() == 3) {
                if (op == "AND") {
                    Parse(pParser, AND, NULL, &state);
                    goto just_had_operator;
                }
                if (op == "NOT") {
                    Parse(pParser, NOT, NULL, &state);
                    goto just_had_operator;
                }
                if (op == "XOR") {
                    Parse(pParser, XOR, NULL, &state);
                    goto just_had_operator;
                }
                if (op == "ADJ") {
                    if (it != end && *it == '/') {
                        size_t width = 0;
                        Utf8Iterator p = it;
                        while (++p != end && U_isdigit(*p)) {
                            width = (width * 10) + (*p - '0');
                        }
                        if (width && (p == end || is_whitespace(*p))) {
                            it = p;
                            Parse(pParser, ADJ, new Term(width), &state);
                            goto just_had_operator;
                        }
                    }

                    Parse(pParser, ADJ, NULL, &state);
                    goto just_had_operator;
                }
            } else if (op.size() == 2) {
                if (op == "OR") {
                    Parse(pParser, OR, NULL, &state);
                    goto just_had_operator;
                }
            } else if (op.size() == 4) {
                if (op == "NEAR") {
                    if (it != end && *it == '/') {
                        size_t width = 0;
                        Utf8Iterator p = it;
                        while (++p != end && U_isdigit(*p)) {
                            width = (width * 10) + (*p - '0');
                        }
                        if (width && (p == end || is_whitespace(*p))) {
                            it = p;
                            Parse(pParser, NEAR, new Term(width), &state);
                            goto just_had_operator;
                        }
                    }

                    Parse(pParser, NEAR, NULL, &state);
                    goto just_had_operator;
                }
            }
        }

        // If no prefix is set, use the default one.
        if (!prefixinfo) prefixinfo = prefix_stack.back();

        Assert(!prefixinfo->filter);

        {
            string unstemmed_term(term);
            term = Unicode::tolower(term);

            // Reuse stem_strategy - STEM_SOME here means "stem terms except
            // when used with positional operators".
            stem_strategy stem_term = stem_action;
            if (stem_term != STEM_NONE) {
                if (!stemmer.internal.get()) {
                    // No stemmer is set.
                    stem_term = STEM_NONE;
                } else if (stem_term == STEM_SOME) {
                    if (!should_stem(unstemmed_term) ||
                        (it != end && is_stem_preventer(*it))) {
                        // Don't stem this particular term.
                        stem_term = STEM_NONE;
                    }
                }
            }

            Term * term_obj = new Term(&state, term, prefixinfo->prefixes,
                                       unstemmed_term, stem_term, term_pos++);

            // Check spelling, if we're a normal term, and any of the prefixes
            // are empty.
            if ((flags & FLAG_SPELLING_CORRECTION) && !was_acronym) {
                list<string>::const_iterator prefixiter;
                for (prefixiter = prefixinfo->prefixes.begin();
                     prefixiter != prefixinfo->prefixes.end();
                     ++prefixiter) {
                    if (!prefixiter->empty())
                        continue;
                    if (!db.term_exists(term)) {
                        string suggestion = db.get_spelling_suggestion(term);
                        if (!suggestion.empty()) {
                            if (corrected_query.empty()) corrected_query = qs;
                            size_t term_end_index = it.raw() - qs.data();
                            size_t n = term_end_index - term_start_index;
                            size_t pos = term_start_index + correction_offset;
                            corrected_query.replace(pos, n, suggestion);
                            correction_offset += suggestion.size();
                            correction_offset -= n;
                        }
                    }
                    break;
                }
            }

            if (mode == IN_PHRASED_TERM) {
                Parse(pParser, PHR_TERM, term_obj, &state);
            } else {
                if (mode == DEFAULT || mode == IN_GROUP) {
                    if (it != end) {
                        if ((flags & FLAG_WILDCARD) && *it == '*') {
                            Utf8Iterator p(it);
                            ++p;
                            if (p == end || !is_wordchar(*p)) {
                                it = p;
                                // Wildcard at end of term (also known as
                                // "right truncation").
                                Parse(pParser, WILD_TERM, term_obj, &state);
                                continue;
                            }
                        }
                    } else {
                        if (flags & FLAG_PARTIAL) {
                            // Final term of a partial match query, with no
                            // following characters - treat as a wildcard.
                            Parse(pParser, PARTIAL_TERM, term_obj, &state);
                            continue;
                        }
                    }
                }

                // See if the next token will be PHR_TERM - if so, this one
                // needs to be TERM not GROUP_TERM.
                if (mode == IN_GROUP && is_phrase_generator(*it)) {
                    // FIXME: can we clean this up?
                    Utf8Iterator p = it;
                    do {
                        ++p;
                    } while (p != end && is_phrase_generator(*p));
                    // Don't generate a phrase unless the phrase generators are
                    // immediately followed by another term.
                    if (p != end && is_wordchar(*p)) {
                        mode = DEFAULT;
                    }
                }

                Parse(pParser, (mode == IN_GROUP ? GROUP_TERM : TERM),
                      term_obj, &state);
                if (mode != DEFAULT && mode != IN_GROUP) continue;
            }
        }

        if (it == end) break;

        if (is_phrase_generator(*it)) {
            // Skip multiple phrase generators.
            do {
                ++it;
            } while (it != end && is_phrase_generator(*it));
            // Don't generate a phrase unless the phrase generators are
            // immediately followed by another term.
            if (it != end && is_wordchar(*it)) {
                mode = IN_PHRASED_TERM;
                term_start_index = it.raw() - qs.data();
                goto phrased_term;
            }
        } else if (mode == DEFAULT || mode == IN_GROUP) {
            mode = DEFAULT;
            if (!last_was_operator && is_whitespace(*it)) {
                newprev = ' ';
                // Skip multiple whitespace.
                do {
                    ++it;
                } while (it != end && is_whitespace(*it));
                // Don't generate a group unless the terms are only separated
                // by whitespace.
                if (it != end && is_wordchar(*it)) {
                    mode = IN_GROUP;
                }
            }
        }
    }
done:
    if (!state.error) {
        // Implicitly close any unclosed quotes...
        if (mode == IN_QUOTES || mode == IN_PREFIXED_QUOTES)
            Parse(pParser, QUOTE, NULL, &state);
        Parse(pParser, 0, NULL, &state);
    }

    errmsg = state.error;
    return state.query;
}

struct ProbQuery {
    Query * query;
    Query * love;
    Query * hate;
    // filter is a map from prefix to a query for that prefix.  Queries with
    // the same prefix are combined with OR, and the results of this are
    // combined with AND to get the full filter.
    map<filter_group_id, Query> filter;

    ProbQuery() : query(0), love(0), hate(0) { }
    ~ProbQuery() {
        delete query;
        delete love;
        delete hate;
    }

    Query merge_filters() const {
        map<filter_group_id, Query>::const_iterator i = filter.begin();
        Assert(i != filter.end());
        Query q = i->second;
        while (++i != filter.end()) {
            q = Query(Query::OP_AND, q, i->second);
        }
        return q;
    }
};

class TermGroup {
    vector<Term *> terms;

  public:
    TermGroup() { }

    void add_term(Term * term) {
        terms.push_back(term);
    }

    Query * as_group(State *state) const;

    void destroy() { delete this; }

  protected:
    ~TermGroup() {
        vector<Term*>::const_iterator i;
        for (i = terms.begin(); i != terms.end(); ++i) {
            delete *i;
        }
    }
};

Query *
TermGroup::as_group(State *state) const
{
    Query::op default_op = state->default_op();
    vector<Query> subqs;
    subqs.reserve(terms.size());
    if (state->flags & QueryParser::FLAG_AUTO_MULTIWORD_SYNONYMS) {
        // Check for multi-word synonyms.
        Database db = state->get_database();

        string key;
        vector<Term*>::const_iterator begin = terms.begin();
        vector<Term*>::const_iterator i = begin;
        while (i != terms.end()) {
            TermIterator synkey(db.synonym_keys_begin((*i)->name));
            TermIterator synend(db.synonym_keys_end((*i)->name));
            if (synkey == synend) {
                // No multi-synonym matches.
                if (state->is_stopword(*i)) {
                    state->add_to_stoplist(*i);
                } else {
                    subqs.push_back((*i)->get_query_with_auto_synonyms());
                }
                begin = ++i;
                continue;
            }
            key.resize(0);
            while (i != terms.end()) {
                if (!key.empty()) key += ' ';
                key += (*i)->name;
                ++i;
                synkey.skip_to(key);
                if (synkey == synend || !startswith(*synkey, key)) break;
            }
            // Greedily try to match as many consecutive words as possible.
            TermIterator syn, end;
            while (true) {
                syn = db.synonyms_begin(key);
                end = db.synonyms_end(key);
                if (syn != end) break;
                if (--i == begin) break;
                key.resize(key.size() - (*i)->name.size() - 1);
            }
            if (i == begin) {
                // No multi-synonym matches.
                if (state->is_stopword(*i)) {
                    state->add_to_stoplist(*i);
                } else {
                    subqs.push_back((*i)->get_query_with_auto_synonyms());
                }
                begin = ++i;
                continue;
            }

            vector<Query> subqs2;
            vector<Term*>::const_iterator j;
            for (j = begin; j != i; ++j) {
                if (state->is_stopword(*j)) {
                    state->add_to_stoplist(*j);
                } else {
                    subqs2.push_back((*j)->get_query());
                }
            }
            Query q_original_terms(default_op, subqs2.begin(), subqs2.end());
            subqs2.clear();

            // Use the position of the first term for the synonyms.
            Xapian::termpos pos = (*begin)->pos;
            begin = i;
            while (syn != end) {
                subqs2.push_back(Query(*syn, 1, pos));
                ++syn;
            }
            Query q_synonym_terms(Query::OP_OR, subqs2.begin(), subqs2.end());
            subqs2.clear();
            subqs.push_back(Query(Query::OP_OR,
                                  q_original_terms, q_synonym_terms));
        }
    } else {
        vector<Term*>::const_iterator i;
        for (i = terms.begin(); i != terms.end(); ++i) {
            if (state->is_stopword(*i)) {
                state->add_to_stoplist(*i);
            } else {
                subqs.push_back((*i)->get_query_with_auto_synonyms());
            }
        }
    }
    delete this;
    if (subqs.empty()) return NULL;
    return new Query(default_op, subqs.begin(), subqs.end());
}

class TermList {
    vector<Term *> terms;
    size_t window;

    bool uniform_prefixes;

    list<string> prefixes;

    Query * as_opwindow_query(Query::op op, Xapian::termcount w_delta) const {
        Query * q = NULL;
        size_t n_terms = terms.size();
        Xapian::termcount w = w_delta + terms.size();
        if (uniform_prefixes) {
            list<string>::const_iterator piter;
            for (piter = prefixes.begin(); piter != prefixes.end(); ++piter) {
                vector<Query> subqs;
                subqs.reserve(n_terms);
                vector<Term *>::const_iterator titer;
                for (titer = terms.begin(); titer != terms.end(); ++titer) {
                    Term * t = *titer;
                    subqs.push_back(Query(t->make_term(*piter), 1, t->pos));
                }
                add_to_query(q, Query::OP_OR,
                             Query(op, subqs.begin(), subqs.end(), w));
            }
        } else {
            vector<Query> subqs;
            subqs.reserve(n_terms);
            vector<Term *>::const_iterator titer;
            for (titer = terms.begin(); titer != terms.end(); ++titer) {
                subqs.push_back((*titer)->get_query());
            }
            q = new Query(op, subqs.begin(), subqs.end(), w);
        }

        delete this;
        return q;
    }

  public:
    TermList() : window(0), uniform_prefixes(true) { }

    void add_positional_term(Term * term) {
        if (terms.empty()) {
            prefixes = term->prefixes;
        } else if (uniform_prefixes && prefixes != term->prefixes)  {
            prefixes.clear();
            uniform_prefixes = false;
        }
        term->need_positions();
        terms.push_back(term);
    }

    void adjust_window(size_t alternative_window) {
        if (alternative_window > window) window = alternative_window;
    }

    Query * as_phrase_query() const {
        return as_opwindow_query(Query::OP_PHRASE, 0);
    }

    Query * as_near_query() const {
        // The common meaning of 'a NEAR b' is "a within 10 terms of b", which
        // means a window size of 11.  For more than 2 terms, we just add one
        // to the window size for each extra term.
        size_t w = window;
        if (w == 0) w = 10;
        return as_opwindow_query(Query::OP_NEAR, w - 1);
    }

    Query * as_adj_query() const {
        // The common meaning of 'a ADJ b' is "a at most 10 terms before b",
        // which means a window size of 11.  For more than 2 terms, we just add
        // one to the window size for each extra term.
        size_t w = window;
        if (w == 0) w = 10;
        return as_opwindow_query(Query::OP_PHRASE, w - 1);
    }

    void destroy() { delete this; }

  protected:
    ~TermList() {
        vector<Term *>::const_iterator t;
        for (t = terms.begin(); t != terms.end(); ++t) {
            delete *t;
        }
    }
};

// Helper macro for converting a boolean operation into a Xapian::Query.
#define BOOL_OP_TO_QUERY(E, A, OP, B, OP_TXT) \
    do {\
        if (!A || !B) {\
            state->error = "Syntax: <expression> "OP_TXT" <expression>";\
            yy_parse_failed(yypParser);\
            return;\
        }\
        E = new Query(OP, *A, *B);\
        delete A;\
        delete B;\
    } while (0)

#line 1381 "queryparser/queryparser_internal.cc"
/* Next is all token values, in a form suitable for use by makeheaders.
** This section will be null unless lemon is run with the -m switch.
*/
/* 
** These constants (all generated automatically by the parser generator)
** specify the various kinds of tokens (terminals) that the parser
** understands. 
**
** Each symbol here is a terminal symbol in the grammar.
*/
/* Make sure the INTERFACE macro is defined.
*/
#ifndef INTERFACE
# define INTERFACE 1
#endif
/* The next thing included is series of defines which control
** various aspects of the generated parser.
**    YYCODETYPE         is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 terminals
**                       and nonterminals.  "int" is used otherwise.
**    YYNOCODE           is a number of type YYCODETYPE which corresponds
**                       to no legal terminal or nonterminal number.  This
**                       number is used to fill in empty slots of the hash 
**                       table.
**    YYFALLBACK         If defined, this indicates that one or more tokens
**                       have fall-back values which should be used if the
**                       original value of the token will not parse.
**    YYACTIONTYPE       is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 rules and
**                       states combined.  "int" is used otherwise.
**    ParseTOKENTYPE     is the data type used for minor tokens given 
**                       directly to the parser from the tokenizer.
**    YYMINORTYPE        is the data type used for all minor tokens.
**                       This is typically a union of many types, one of
**                       which is ParseTOKENTYPE.  The entry in the union
**                       for base tokens is called "yy0".
**    YYSTACKDEPTH       is the maximum depth of the parser's stack.
**    ParseARG_SDECL     A static variable declaration for the %extra_argument
**    ParseARG_PDECL     A parameter declaration for the %extra_argument
**    ParseARG_STORE     Code to store %extra_argument into yypParser
**    ParseARG_FETCH     Code to extract %extra_argument from yypParser
**    YYNSTATE           the combined number of states.
**    YYNRULE            the number of rules in the grammar
**    YYERRORSYMBOL      is the code number of the error symbol.  If not
**                       defined, then do no error processing.
*/
#define YYCODETYPE unsigned char
#define YYNOCODE 39
#define YYACTIONTYPE unsigned char
#define ParseTOKENTYPE Term *
typedef union {
  ParseTOKENTYPE yy0;
  int yy8;
  ProbQuery * yy12;
  TermList * yy27;
  Query * yy73;
  TermGroup * yy76;
  int yy77;
} YYMINORTYPE;
#define YYSTACKDEPTH 100
#define ParseARG_SDECL State * state;
#define ParseARG_PDECL ,State * state
#define ParseARG_FETCH State * state = yypParser->state
#define ParseARG_STORE yypParser->state = state
#define YYNSTATE 75
#define YYNRULE 52
#define YYERRORSYMBOL 23
#define YYERRSYMDT yy77
#define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
#define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
#define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)

/* Next are that tables used to determine what action to take based on the
** current state and lookahead token.  These tables are used to implement
** functions that take a state number and lookahead value and return an
** action integer.  
**
** Suppose the action integer is N.  Then the action is determined as
** follows
**
**   0 <= N < YYNSTATE                  Shift N.  That is, push the lookahead
**                                      token onto the stack and goto state N.
**
**   YYNSTATE <= N < YYNSTATE+YYNRULE   Reduce by rule N-YYNSTATE.
**
**   N == YYNSTATE+YYNRULE              A syntax error has occurred.
**
**   N == YYNSTATE+YYNRULE+1            The parser accepts its input.
**
**   N == YYNSTATE+YYNRULE+2            No such action.  Denotes unused
**                                      slots in the yy_action[] table.
**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as
**
**      yy_action[ yy_shift_ofst[S] + X ]
**
** If the index value yy_shift_ofst[S]+X is out of range or if the value
** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
** and that yy_default[S] should be used instead.  
**
** The formula above is for computing the action when the lookahead is
** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
** YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**
**  yy_action[]        A single table containing all actions.
**  yy_lookahead[]     A table containing the lookahead for each entry in
**                     yy_action.  Used to detect hash collisions.
**  yy_shift_ofst[]    For each state, the offset into yy_action for
**                     shifting terminals.
**  yy_reduce_ofst[]   For each state, the offset into yy_action for
**                     shifting non-terminals after a reduce.
**  yy_default[]       Default action for each state.
*/
static const YYACTIONTYPE yy_action[] = {
 /*     0 */   128,    1,    2,    3,   13,   43,   46,   60,   70,   19,
 /*    10 */    30,   32,   34,   37,   71,    4,    6,   62,   65,   73,
 /*    20 */    54,   69,   75,   26,   23,   24,   68,   44,   21,   25,
 /*    30 */    40,   12,    2,    5,   13,   43,   46,   60,   70,   29,
 /*    40 */    30,   32,   34,   37,   12,    2,    7,   13,   43,   46,
 /*    50 */    60,   70,   31,   30,   32,   34,   37,   12,    2,    9,
 /*    60 */    13,   43,   46,   60,   70,   33,   30,   32,   34,   37,
 /*    70 */    12,    2,   11,   13,   43,   46,   60,   70,   35,   30,
 /*    80 */    32,   34,   37,   41,    2,    3,   13,   43,   46,   60,
 /*    90 */    70,   36,   30,   32,   34,   37,   12,    2,   72,   13,
 /*   100 */    43,   46,   60,   70,   38,   30,   32,   34,   37,   12,
 /*   110 */     2,   74,   13,   43,   46,   60,   70,   76,   30,   32,
 /*   120 */    34,   37,   10,    4,    6,   62,   65,   39,   54,   69,
 /*   130 */    49,   56,   23,   24,   68,   44,   42,   25,   40,   59,
 /*   140 */    47,   62,   65,   45,   54,   69,   48,   28,   23,   24,
 /*   150 */    68,   44,   55,   25,   40,   27,   92,  102,  102,   92,
 /*   160 */    54,   15,   92,   92,   23,   24,  102,  102,   92,   25,
 /*   170 */    40,  106,   92,  106,  106,  106,  106,   18,   20,    8,
 /*   180 */    10,    4,    6,   92,   17,   16,   54,   52,   92,   92,
 /*   190 */    23,   24,   51,  106,   92,   25,   40,   54,   52,   92,
 /*   200 */    92,   23,   24,   58,   54,   52,   25,   40,   23,   24,
 /*   210 */    64,   92,   92,   25,   40,   54,   52,   92,   92,   23,
 /*   220 */    24,   67,   92,   92,   25,   40,   92,   14,   22,   92,
 /*   230 */    30,   32,   34,   37,   50,   92,   92,   53,   92,   30,
 /*   240 */    32,   34,   37,   57,   92,   92,   53,   92,   30,   32,
 /*   250 */    34,   37,   54,   15,   92,   92,   23,   24,   92,   92,
 /*   260 */    92,   25,   40,   61,   22,   92,   30,   32,   34,   37,
 /*   270 */    92,   63,   92,   92,   53,   92,   30,   32,   34,   37,
 /*   280 */    66,   92,   92,   53,   92,   30,   32,   34,   37,  107,
 /*   290 */    92,  107,  107,  107,  107,   92,   18,   20,   92,   92,
 /*   300 */    92,   92,   92,   17,   16,   92,   92,   92,   92,   92,
 /*   310 */    92,  107,
};
static const YYCODETYPE yy_lookahead[] = {
 /*     0 */    24,   25,   26,   27,   28,   29,   30,   31,   32,   12,
 /*    10 */    34,   35,   36,   37,    5,    4,    5,    8,    9,   10,
 /*    20 */    11,   12,    0,   33,   15,   16,   17,   18,   12,   20,
 /*    30 */    21,   25,   26,   27,   28,   29,   30,   31,   32,   12,
 /*    40 */    34,   35,   36,   37,   25,   26,   27,   28,   29,   30,
 /*    50 */    31,   32,   14,   34,   35,   36,   37,   25,   26,   27,
 /*    60 */    28,   29,   30,   31,   32,   13,   34,   35,   36,   37,
 /*    70 */    25,   26,   27,   28,   29,   30,   31,   32,    6,   34,
 /*    80 */    35,   36,   37,   25,   26,   27,   28,   29,   30,   31,
 /*    90 */    32,   12,   34,   35,   36,   37,   25,   26,   27,   28,
 /*   100 */    29,   30,   31,   32,    7,   34,   35,   36,   37,   25,
 /*   110 */    26,   27,   28,   29,   30,   31,   32,    0,   34,   35,
 /*   120 */    36,   37,    3,    4,    5,    8,    9,   12,   11,   12,
 /*   130 */     8,    9,   15,   16,   17,   18,   22,   20,   21,   17,
 /*   140 */    18,    8,    9,   19,   11,   12,   19,   12,   15,   16,
 /*   150 */    17,   18,   12,   20,   21,   20,   38,    8,    9,   38,
 /*   160 */    11,   12,   38,   38,   15,   16,   17,   18,   38,   20,
 /*   170 */    21,    0,   38,    2,    3,    4,    5,    6,    7,    2,
 /*   180 */     3,    4,    5,   38,   13,   14,   11,   12,   38,   38,
 /*   190 */    15,   16,   17,   22,   38,   20,   21,   11,   12,   38,
 /*   200 */    38,   15,   16,   17,   11,   12,   20,   21,   15,   16,
 /*   210 */    17,   38,   38,   20,   21,   11,   12,   38,   38,   15,
 /*   220 */    16,   17,   38,   38,   20,   21,   38,   31,   32,   38,
 /*   230 */    34,   35,   36,   37,   29,   38,   38,   32,   38,   34,
 /*   240 */    35,   36,   37,   29,   38,   38,   32,   38,   34,   35,
 /*   250 */    36,   37,   11,   12,   38,   38,   15,   16,   38,   38,
 /*   260 */    38,   20,   21,   31,   32,   38,   34,   35,   36,   37,
 /*   270 */    38,   29,   38,   38,   32,   38,   34,   35,   36,   37,
 /*   280 */    29,   38,   38,   32,   38,   34,   35,   36,   37,    0,
 /*   290 */    38,    2,    3,    4,    5,   38,    6,    7,   38,   38,
 /*   300 */    38,   38,   38,   13,   14,   38,   38,   38,   38,   38,
 /*   310 */    38,   22,
};
#define YY_SHIFT_USE_DFLT (-4)
static const short yy_shift_ofst[] = {
 /*     0 */   117,   22,   -4,  177,    9,   -4,  133,   -4,  133,  119,
 /*    10 */   133,   11,   -4,  149,   -4,  290,   -4,   -4,   -3,   -4,
 /*    20 */    16,   -4,   -4,   -4,   -4,   27,  135,   -4,   -4,   -4,
 /*    30 */    38,   -4,   52,   -4,   72,   79,   -4,   97,  115,   -4,
 /*    40 */   133,  114,   -4,   -4,  124,   -4,  122,  127,   -4,  175,
 /*    50 */    -4,   -4,  290,   -4,  140,   -4,  186,   -4,   -4,   -4,
 /*    60 */   241,   -4,  193,   -4,   -4,  204,   -4,   -4,   -4,  171,
 /*    70 */   289,  133,   -4,  133,   -4,
};
#define YY_REDUCE_USE_DFLT (-25)
static const short yy_reduce_ofst[] = {
 /*     0 */   -24,  -25,  -25,  -25,    6,  -25,   19,  -25,   32,  -25,
 /*    10 */    45,  -25,  -25,  196,  -25,  -25,  -25,  -25,  -25,  -25,
 /*    20 */   -25,  -25,  -25,  -25,  -25,  -10,  -25,  -25,  -25,  -25,
 /*    30 */   -25,  -25,  -25,  -25,  -25,  -25,  -25,  -25,  -25,  -25,
 /*    40 */    58,  -25,  -25,  -25,  -25,  -25,  -25,  -25,  -25,  205,
 /*    50 */   -25,  -25,  -25,  -25,  -25,  -25,  214,  -25,  -25,  -25,
 /*    60 */   232,  -25,  242,  -25,  -25,  251,  -25,  -25,  -25,  -25,
 /*    70 */   -25,   71,  -25,   84,  -25,
};
static const YYACTIONTYPE yy_default[] = {
 /*     0 */    85,   84,   77,  127,   85,   78,   85,   79,   85,   82,
 /*    10 */    85,   83,   84,   86,   91,  104,  119,  121,  127,  123,
 /*    20 */   127,  125,  105,  108,  109,  127,  127,  110,  118,  117,
 /*    30 */   111,  120,  112,  122,  113,  127,  124,  114,  127,  126,
 /*    40 */    85,   84,  115,   87,  127,   88,  127,  127,   89,  127,
 /*    50 */    93,  101,  106,  107,  127,  116,  127,   95,   97,   99,
 /*    60 */   103,   90,  127,   92,  100,  127,   94,   96,   98,  104,
 /*    70 */   105,   85,   80,   85,   81,
};
#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))

/* The next table maps tokens into fallback tokens.  If a construct
** like the following:
** 
**      %fallback ID X Y Z.
**
** appears in the grammar, then ID becomes a fallback token for X, Y,
** and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
** but it does not parse, the type of the token is changed to ID and
** the parse is retried before an error is thrown.
*/
#ifdef YYFALLBACK
static const YYCODETYPE yyFallback[] = {
};
#endif /* YYFALLBACK */

/* The following structure represents a single element of the
** parser's stack.  Information stored includes:
**
**   +  The state number for the parser at this level of the stack.
**
**   +  The value of the token stored at this level of the stack.
**      (In other words, the "major" token.)
**
**   +  The semantic value stored at this level of the stack.  This is
**      the information used by the action routines in the grammar.
**      It is sometimes called the "minor" token.
*/
struct yyStackEntry {
  yyStackEntry() {
    stateno = 0;
    major = 0;
  }
  yyStackEntry(int stateno_, int major_, YYMINORTYPE minor_)
  {
    stateno = stateno_;
    major = major_;
    minor = minor_;
  }
  int stateno;       /* The state-number */
  int major;         /* The major token value.  This is the code
                     ** number for the token at this stack level */
  YYMINORTYPE minor; /* The user-supplied minor token value.  This
                     ** is the value of the token  */
};

/* The state of the parser is completely contained in an instance of
** the following structure */
struct yyParser {
  int yyerrcnt;                 /* Shifts left before out of the error */
  ParseARG_SDECL                /* A place to hold %extra_argument */
  vector<yyStackEntry> yystack; /* The parser's stack */
};
typedef struct yyParser yyParser;

/* Prototype this here so we can call it from a rule action (ick). */
static void yy_parse_failed(yyParser *);

#include "omdebug.h"

#ifdef XAPIAN_DEBUG_VERBOSE
/* For tracing shifts, the names of all terminals and nonterminals
** are required.  The following table supplies these names */
static const char *const yyTokenName[] = {
  "$",             "ERROR",         "OR",            "XOR",         
  "AND",           "NOT",           "NEAR",          "ADJ",         
  "LOVE",          "HATE",          "HATE_AFTER_AND",  "SYNONYM",     
  "TERM",          "GROUP_TERM",    "PHR_TERM",      "WILD_TERM",   
  "PARTIAL_TERM",  "BOOLEAN_FILTER",  "RANGE_START",   "RANGE_END",   
  "QUOTE",         "BRA",           "KET",           "error",       
  "query",         "expr",          "prob_expr",     "bool_arg",    
  "prob",          "term",          "stop_prob",     "stop_term",   
  "compound_term",  "phrase",        "phrased_term",  "group",       
  "near_expr",     "adj_expr",    
};

/* For tracing reduce actions, the names of all rules are required.
*/
static const char *const yyRuleName[] = {
 /*   0 */ "query ::= expr",
 /*   1 */ "query ::=",
 /*   2 */ "expr ::= prob_expr",
 /*   3 */ "expr ::= bool_arg AND bool_arg",
 /*   4 */ "expr ::= bool_arg NOT bool_arg",
 /*   5 */ "expr ::= bool_arg AND NOT bool_arg",
 /*   6 */ "expr ::= bool_arg AND HATE_AFTER_AND bool_arg",
 /*   7 */ "expr ::= bool_arg OR bool_arg",
 /*   8 */ "expr ::= bool_arg XOR bool_arg",
 /*   9 */ "bool_arg ::= expr",
 /*  10 */ "bool_arg ::=",
 /*  11 */ "prob_expr ::= prob",
 /*  12 */ "prob_expr ::= term",
 /*  13 */ "prob ::= RANGE_START RANGE_END",
 /*  14 */ "prob ::= stop_prob RANGE_START RANGE_END",
 /*  15 */ "prob ::= stop_term stop_term",
 /*  16 */ "prob ::= prob stop_term",
 /*  17 */ "prob ::= LOVE term",
 /*  18 */ "prob ::= stop_prob LOVE term",
 /*  19 */ "prob ::= HATE term",
 /*  20 */ "prob ::= stop_prob HATE term",
 /*  21 */ "prob ::= HATE BOOLEAN_FILTER",
 /*  22 */ "prob ::= stop_prob HATE BOOLEAN_FILTER",
 /*  23 */ "prob ::= BOOLEAN_FILTER",
 /*  24 */ "prob ::= stop_prob BOOLEAN_FILTER",
 /*  25 */ "prob ::= LOVE BOOLEAN_FILTER",
 /*  26 */ "prob ::= stop_prob LOVE BOOLEAN_FILTER",
 /*  27 */ "stop_prob ::= prob",
 /*  28 */ "stop_prob ::= stop_term",
 /*  29 */ "stop_term ::= TERM",
 /*  30 */ "stop_term ::= compound_term",
 /*  31 */ "term ::= TERM",
 /*  32 */ "term ::= compound_term",
 /*  33 */ "compound_term ::= WILD_TERM",
 /*  34 */ "compound_term ::= PARTIAL_TERM",
 /*  35 */ "compound_term ::= QUOTE phrase QUOTE",
 /*  36 */ "compound_term ::= phrased_term",
 /*  37 */ "compound_term ::= group",
 /*  38 */ "compound_term ::= near_expr",
 /*  39 */ "compound_term ::= adj_expr",
 /*  40 */ "compound_term ::= BRA expr KET",
 /*  41 */ "compound_term ::= SYNONYM TERM",
 /*  42 */ "phrase ::= TERM",
 /*  43 */ "phrase ::= phrase TERM",
 /*  44 */ "phrased_term ::= TERM PHR_TERM",
 /*  45 */ "phrased_term ::= phrased_term PHR_TERM",
 /*  46 */ "group ::= TERM GROUP_TERM",
 /*  47 */ "group ::= group GROUP_TERM",
 /*  48 */ "near_expr ::= TERM NEAR TERM",
 /*  49 */ "near_expr ::= near_expr NEAR TERM",
 /*  50 */ "adj_expr ::= TERM ADJ TERM",
 /*  51 */ "adj_expr ::= adj_expr ADJ TERM",
};

/*
** This function returns the symbolic name associated with a token
** value.
*/
static const char *ParseTokenName(int tokenType){
  if( tokenType>0 && size_t(tokenType)<(sizeof(yyTokenName)/sizeof(yyTokenName[0])) ){
    return yyTokenName[tokenType];
  }
  return "Unknown";
}

/*
** This function returns the symbolic name associated with a rule
** value.
*/
static const char *ParseRuleName(int ruleNum){
  if( ruleNum>0 && size_t(ruleNum)<(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
    return yyRuleName[ruleNum];
  }
  return "Unknown";
}
#endif /* XAPIAN_DEBUG_VERBOSE */

/* 
** This function allocates a new parser.
** The only argument is a pointer to a function which works like
** malloc.
**
** Inputs:
** None.
**
** Outputs:
** A pointer to a parser.  This pointer is used in subsequent calls
** to Parse and ParseFree.
*/
static yyParser *ParseAlloc(){
  return new yyParser;
}

/* The following function deletes the value associated with a
** symbol.  The symbol can be either a terminal or nonterminal.
** "yymajor" is the symbol code, and "yypminor" is a pointer to
** the value.
*/
static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
  switch( yymajor ){
    /* Here is inserted the actions which take place when a
    ** terminal or non-terminal is destroyed.  This can happen
    ** when the symbol is popped from the stack during a
    ** reduce or during error processing or when a parser is 
    ** being destroyed before it is finished parsing.
    **
    ** Note: during a reduce, the only symbols destroyed are those
    ** which appear on the RHS of the rule, but which are not used
    ** inside the C code.
    */
    case 1:
    case 2:
    case 3:
    case 4:
    case 5:
    case 6:
    case 7:
    case 8:
    case 9:
    case 10:
    case 11:
    case 12:
    case 13:
    case 14:
    case 15:
    case 16:
    case 17:
    case 18:
    case 19:
    case 20:
    case 21:
    case 22:
#line 1376 "queryparser/queryparser.lemony"
{delete (yypminor->yy0);}
#line 1817 "queryparser/queryparser_internal.cc"
      break;
    case 25:
    case 26:
    case 27:
    case 29:
    case 31:
    case 32:
#line 1447 "queryparser/queryparser.lemony"
{delete (yypminor->yy73);}
#line 1827 "queryparser/queryparser_internal.cc"
      break;
    case 28:
    case 30:
#line 1543 "queryparser/queryparser.lemony"
{delete (yypminor->yy12);}
#line 1833 "queryparser/queryparser_internal.cc"
      break;
    case 33:
    case 34:
    case 36:
    case 37:
#line 1744 "queryparser/queryparser.lemony"
{(yypminor->yy27)->destroy();}
#line 1841 "queryparser/queryparser_internal.cc"
      break;
    case 35:
#line 1778 "queryparser/queryparser.lemony"
{(yypminor->yy76)->destroy();}
#line 1846 "queryparser/queryparser_internal.cc"
      break;
    default:  break;   /* If no destructor action specified: do nothing */
  }
}

/*
** Pop the parser's stack once.
**
** If there is a destructor routine associated with the token which
** is popped from the stack, then call it.
**
** Return the major token number for the symbol popped.
*/
static int yy_pop_parser_stack(yyParser *pParser){
  YYCODETYPE yymajor;
  if( pParser->yystack.empty() ) return 0;
  yyStackEntry *yytos = &pParser->yystack.back();

  DEBUGLINE(QUERYPARSER, "Popping " << ParseTokenName(yytos->major));
  yymajor = (YYCODETYPE)yytos->major;
  yy_destructor( yymajor, &yytos->minor);
  pParser->yystack.pop_back();
  return yymajor;
}

/* 
** Deallocate and destroy a parser.  Destructors are all called for
** all stack elements before shutting the parser down.
**
** Inputs:
** A pointer to the parser.  This should be a pointer
** obtained from ParseAlloc.
*/
static void ParseFree(
  yyParser *pParser           /* The parser to be deleted */
){
  if( pParser==0 ) return;
  while( !pParser->yystack.empty() ) yy_pop_parser_stack(pParser);
  delete pParser;
}

/*
** Find the appropriate action for a parser given the terminal
** look-ahead token iLookAhead.
**
** If the look-ahead token is YYNOCODE, then check to see if the action is
** independent of the look-ahead.  If it is, return the action, otherwise
** return YY_NO_ACTION.
*/
static int yy_find_shift_action(
  yyParser *pParser,        /* The parser */
  int iLookAhead            /* The look-ahead token */
){
  int i;
  /* if( pParser->yystack.empty() ) return YY_NO_ACTION;  */
  int stateno = pParser->yystack.back().stateno;
 
  i = yy_shift_ofst[stateno];
  if( i==YY_SHIFT_USE_DFLT ){
    return yy_default[stateno];
  }
  if( iLookAhead==YYNOCODE ){
    return YY_NO_ACTION;
  }
  i += iLookAhead;
  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
#ifdef YYFALLBACK
    int iFallback;            /* Fallback token */
    if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
           && (iFallback = yyFallback[iLookAhead])!=0 ){
      DEBUGLINE(QUERYPARSER,
                "FALLBACK " << ParseTokenName(iLookAhead) << " => " <<
                ParseTokenName(iFallback));
      return yy_find_shift_action(pParser, iFallback);
    }
#endif
    return yy_default[stateno];
  }else{
    return yy_action[i];
  }
}

/*
** Find the appropriate action for a parser given the non-terminal
** look-ahead token iLookAhead.
**
** If the look-ahead token is YYNOCODE, then check to see if the action is
** independent of the look-ahead.  If it is, return the action, otherwise
** return YY_NO_ACTION.
*/
static int yy_find_reduce_action(
  yyParser *pParser,        /* The parser */
  int iLookAhead            /* The look-ahead token */
){
  int i;
  int stateno = pParser->yystack.back().stateno;
 
  i = yy_reduce_ofst[stateno];
  if( i==YY_REDUCE_USE_DFLT ){
    return yy_default[stateno];
  }
  if( iLookAhead==YYNOCODE ){
    return YY_NO_ACTION;
  }
  i += iLookAhead;
  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
    return yy_default[stateno];
  }else{
    return yy_action[i];
  }
}

/*
** Perform a shift action.
*/
static void yy_shift(
  yyParser *yypParser,          /* The parser to be shifted */
  int yyNewState,               /* The new state to shift in */
  int yyMajor,                  /* The major token to shift in */
  YYMINORTYPE *yypMinor         /* Pointer to the minor token to shift in */
){
  /* Here code is inserted which will execute if the parser
  ** stack every overflows.  We use std::vector<> for our stack
  ** so we'll never need this code.
  */
#if 0
#endif
#ifdef XAPIAN_DEBUG_VERBOSE
  unsigned i;
  DEBUGLINE(QUERYPARSER, "Shift " << yyNewState);
  string stack("Stack:");
  for (i = 0; i < yypParser->yystack.size(); i++) {
    stack += ' ';
    stack += ParseTokenName(yypParser->yystack[i].major);
  }
  DEBUGLINE(QUERYPARSER, stack);
#endif
  yypParser->yystack.push_back(yyStackEntry(yyNewState, yyMajor, *yypMinor));
}

/* The following table contains information about every rule that
** is used during the reduce.
*/
static const struct {
  YYCODETYPE lhs;         /* Symbol on the left-hand side of the rule */
  unsigned char nrhs;     /* Number of right-hand side symbols in the rule */
} yyRuleInfo[] = {
  { 24, 1 },
  { 24, 0 },
  { 25, 1 },
  { 25, 3 },
  { 25, 3 },
  { 25, 4 },
  { 25, 4 },
  { 25, 3 },
  { 25, 3 },
  { 27, 1 },
  { 27, 0 },
  { 26, 1 },
  { 26, 1 },
  { 28, 2 },
  { 28, 3 },
  { 28, 2 },
  { 28, 2 },
  { 28, 2 },
  { 28, 3 },
  { 28, 2 },
  { 28, 3 },
  { 28, 2 },
  { 28, 3 },
  { 28, 1 },
  { 28, 2 },
  { 28, 2 },
  { 28, 3 },
  { 30, 1 },
  { 30, 1 },
  { 31, 1 },
  { 31, 1 },
  { 29, 1 },
  { 29, 1 },
  { 32, 1 },
  { 32, 1 },
  { 32, 3 },
  { 32, 1 },
  { 32, 1 },
  { 32, 1 },
  { 32, 1 },
  { 32, 3 },
  { 32, 2 },
  { 33, 1 },
  { 33, 2 },
  { 34, 2 },
  { 34, 2 },
  { 35, 2 },
  { 35, 2 },
  { 36, 3 },
  { 36, 3 },
  { 37, 3 },
  { 37, 3 },
};

static void yy_accept(yyParser*);  /* Forward Declaration */

/*
** Perform a reduce action and the shift that must immediately
** follow the reduce.
*/
static void yy_reduce(
  yyParser *yypParser,         /* The parser */
  int yyruleno                 /* Number of the rule by which to reduce */
){
  int yygoto;                     /* The next state */
  int yyact;                      /* The next action */
  YYMINORTYPE yygotominor;        /* The LHS of the rule reduced */
  yyStackEntry *yymsp;            /* The top of the parser's stack */
  int yysize;                     /* Amount to pop the stack */
  ParseARG_FETCH;
  yymsp = &yypParser->yystack.back();
#ifdef XAPIAN_DEBUG_VERBOSE
  DEBUGLINE(QUERYPARSER, "Reduce [" << ParseRuleName(yyruleno) << "].");
#endif

  switch( yyruleno ){
  /* Beginning here are the reduction cases.  A typical example
  ** follows:
  **   case 0:
  **  #line <lineno> <grammarfile>
  **     { ... }           // User supplied code
  **  #line <lineno> <thisfile>
  **     break;
  */
      case 0:
#line 1429 "queryparser/queryparser.lemony"
{
    // Save the parsed query in the State structure so we can return it.
    if (yymsp[0].minor.yy73) {
        state->query = *yymsp[0].minor.yy73;
        delete yymsp[0].minor.yy73;
    } else {
        state->query = Query();
    }
}
#line 2089 "queryparser/queryparser_internal.cc"
        break;
      case 1:
#line 1439 "queryparser/queryparser.lemony"
{
    // Handle a query string with no terms in.
    state->query = Query();
}
#line 2097 "queryparser/queryparser_internal.cc"
        break;
      case 2:
      case 9:
#line 1450 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy73; }
#line 2103 "queryparser/queryparser_internal.cc"
        break;
      case 3:
#line 1453 "queryparser/queryparser.lemony"
{ BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-2].minor.yy73, Query::OP_AND, yymsp[0].minor.yy73, "AND");   yy_destructor(4,&yymsp[-1].minor);
}
#line 2109 "queryparser/queryparser_internal.cc"
        break;
      case 4:
#line 1455 "queryparser/queryparser.lemony"
{
    // 'NOT foo' -> '<alldocuments> NOT foo'
    if (!yymsp[-2].minor.yy73 && (state->flags & QueryParser::FLAG_PURE_NOT)) {
        yymsp[-2].minor.yy73 = new Query("", 1, 0);
    }
    BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-2].minor.yy73, Query::OP_AND_NOT, yymsp[0].minor.yy73, "NOT");
  yy_destructor(5,&yymsp[-1].minor);
}
#line 2121 "queryparser/queryparser_internal.cc"
        break;
      case 5:
#line 1464 "queryparser/queryparser.lemony"
{ BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-3].minor.yy73, Query::OP_AND_NOT, yymsp[0].minor.yy73, "AND NOT");   yy_destructor(4,&yymsp[-2].minor);
  yy_destructor(5,&yymsp[-1].minor);
}
#line 2128 "queryparser/queryparser_internal.cc"
        break;
      case 6:
#line 1467 "queryparser/queryparser.lemony"
{ BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-3].minor.yy73, Query::OP_AND_NOT, yymsp[0].minor.yy73, "AND");   yy_destructor(4,&yymsp[-2].minor);
  yy_destructor(10,&yymsp[-1].minor);
}
#line 2135 "queryparser/queryparser_internal.cc"
        break;
      case 7:
#line 1470 "queryparser/queryparser.lemony"
{ BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-2].minor.yy73, Query::OP_OR, yymsp[0].minor.yy73, "OR");   yy_destructor(2,&yymsp[-1].minor);
}
#line 2141 "queryparser/queryparser_internal.cc"
        break;
      case 8:
#line 1473 "queryparser/queryparser.lemony"
{ BOOL_OP_TO_QUERY(yygotominor.yy73, yymsp[-2].minor.yy73, Query::OP_XOR, yymsp[0].minor.yy73, "XOR");   yy_destructor(3,&yymsp[-1].minor);
}
#line 2147 "queryparser/queryparser_internal.cc"
        break;
      case 10:
#line 1482 "queryparser/queryparser.lemony"
{
    // Set the argument to NULL, which enables the bool_arg-using rules in
    // expr above to report uses of AND, OR, etc which don't have two
    // arguments.
    yygotominor.yy73 = NULL;
}
#line 2157 "queryparser/queryparser_internal.cc"
        break;
      case 11:
#line 1494 "queryparser/queryparser.lemony"
{
    yygotominor.yy73 = yymsp[0].minor.yy12->query;
    yymsp[0].minor.yy12->query = NULL;
    // Handle any "+ terms".
    if (yymsp[0].minor.yy12->love) {
        if (yymsp[0].minor.yy12->love->empty()) {
            // +<nothing>.
            delete yygotominor.yy73;
            yygotominor.yy73 = yymsp[0].minor.yy12->love;
        } else if (yygotominor.yy73) {
            swap(yygotominor.yy73, yymsp[0].minor.yy12->love);
            add_to_query(yygotominor.yy73, Query::OP_AND_MAYBE, yymsp[0].minor.yy12->love);
        } else {
            yygotominor.yy73 = yymsp[0].minor.yy12->love;
        }
        yymsp[0].minor.yy12->love = NULL;
    }
    // Handle any boolean filters.
    if (!yymsp[0].minor.yy12->filter.empty()) {
        if (yygotominor.yy73) {
            add_to_query(yygotominor.yy73, Query::OP_FILTER, yymsp[0].minor.yy12->merge_filters());
        } else {
            // Make the query a boolean one.
            yygotominor.yy73 = new Query(Query::OP_SCALE_WEIGHT, yymsp[0].minor.yy12->merge_filters(), 0.0);
        }
    }
    // Handle any "- terms".
    if (yymsp[0].minor.yy12->hate && !yymsp[0].minor.yy12->hate->empty()) {
        if (!yygotominor.yy73) {
            // Can't just hate!
            yy_parse_failed(yypParser);
            return;
        }
        *yygotominor.yy73 = Query(Query::OP_AND_NOT, *yygotominor.yy73, *yymsp[0].minor.yy12->hate);
    }
    // FIXME what if yygotominor.yy73 && yygotominor.yy73->empty() (all terms are stopwords)?
    delete yymsp[0].minor.yy12;
}
#line 2199 "queryparser/queryparser_internal.cc"
        break;
      case 12:
      case 30:
      case 32:
#line 1533 "queryparser/queryparser.lemony"
{
    yygotominor.yy73 = yymsp[0].minor.yy73;
}
#line 2208 "queryparser/queryparser_internal.cc"
        break;
      case 13:
#line 1545 "queryparser/queryparser.lemony"
{
    Query range;
    Xapian::valueno valno = state->value_range(range, yymsp[-1].minor.yy0, yymsp[0].minor.yy0);
    if (valno == BAD_VALUENO) {
        yy_parse_failed(yypParser);
        return;
    }
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->filter[filter_group_id(valno)] = range;
}
#line 2222 "queryparser/queryparser_internal.cc"
        break;
      case 14:
#line 1556 "queryparser/queryparser.lemony"
{
    Query range;
    Xapian::valueno valno = state->value_range(range, yymsp[-1].minor.yy0, yymsp[0].minor.yy0);
    if (valno == BAD_VALUENO) {
        yy_parse_failed(yypParser);
        return;
    }
    yygotominor.yy12 = yymsp[-2].minor.yy12;
    Query & q = yygotominor.yy12->filter[filter_group_id(valno)];
    q = Query(Query::OP_OR, q, range);
}
#line 2237 "queryparser/queryparser_internal.cc"
        break;
      case 15:
#line 1568 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->query = yymsp[-1].minor.yy73;
    if (yymsp[0].minor.yy73) add_to_query(yygotominor.yy12->query, state->default_op(), yymsp[0].minor.yy73);
}
#line 2246 "queryparser/queryparser_internal.cc"
        break;
      case 16:
#line 1574 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = yymsp[-1].minor.yy12;
    // If yymsp[0].minor.yy73 is a stopword, there's nothing to do here.
    if (yymsp[0].minor.yy73) add_to_query(yygotominor.yy12->query, state->default_op(), yymsp[0].minor.yy73);
}
#line 2255 "queryparser/queryparser_internal.cc"
        break;
      case 17:
#line 1580 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    if (state->default_op() == Query::OP_AND) {
        yygotominor.yy12->query = yymsp[0].minor.yy73;
    } else {
        yygotominor.yy12->love = yymsp[0].minor.yy73;
    }
  yy_destructor(8,&yymsp[-1].minor);
}
#line 2268 "queryparser/queryparser_internal.cc"
        break;
      case 18:
#line 1589 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = yymsp[-2].minor.yy12;
    if (state->default_op() == Query::OP_AND) {
        /* The default op is AND, so we just put loved terms into the query
         * (in this case the only effect of love is to ignore the stopword
         * list). */
        add_to_query(yygotominor.yy12->query, Query::OP_AND, yymsp[0].minor.yy73);
    } else {
        add_to_query(yygotominor.yy12->love, Query::OP_AND, yymsp[0].minor.yy73);
    }
  yy_destructor(8,&yymsp[-1].minor);
}
#line 2284 "queryparser/queryparser_internal.cc"
        break;
      case 19:
#line 1601 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->hate = yymsp[0].minor.yy73;
  yy_destructor(9,&yymsp[-1].minor);
}
#line 2293 "queryparser/queryparser_internal.cc"
        break;
      case 20:
#line 1606 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = yymsp[-2].minor.yy12;
    add_to_query(yygotominor.yy12->hate, Query::OP_OR, yymsp[0].minor.yy73);
  yy_destructor(9,&yymsp[-1].minor);
}
#line 2302 "queryparser/queryparser_internal.cc"
        break;
      case 21:
#line 1611 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->hate = new Query(yymsp[0].minor.yy0->get_query());
    delete yymsp[0].minor.yy0;
  yy_destructor(9,&yymsp[-1].minor);
}
#line 2312 "queryparser/queryparser_internal.cc"
        break;
      case 22:
#line 1617 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = yymsp[-2].minor.yy12;
    add_to_query(yygotominor.yy12->hate, Query::OP_OR, yymsp[0].minor.yy0->get_query());
    delete yymsp[0].minor.yy0;
  yy_destructor(9,&yymsp[-1].minor);
}
#line 2322 "queryparser/queryparser_internal.cc"
        break;
      case 23:
#line 1623 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->filter[yymsp[0].minor.yy0->get_filter_group_id()] = yymsp[0].minor.yy0->get_query();
    delete yymsp[0].minor.yy0;
}
#line 2331 "queryparser/queryparser_internal.cc"
        break;
      case 24:
#line 1629 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = yymsp[-1].minor.yy12;
    // We OR filters with the same prefix...
    Query & q = yygotominor.yy12->filter[yymsp[0].minor.yy0->get_filter_group_id()];
    q = Query(Query::OP_OR, q, yymsp[0].minor.yy0->get_query());
    delete yymsp[0].minor.yy0;
}
#line 2342 "queryparser/queryparser_internal.cc"
        break;
      case 25:
#line 1637 "queryparser/queryparser.lemony"
{
    // LOVE BOOLEAN_FILTER(yymsp[0].minor.yy0) is just the same as BOOLEAN_FILTER
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->filter[yymsp[0].minor.yy0->get_filter_group_id()] = yymsp[0].minor.yy0->get_query();
    delete yymsp[0].minor.yy0;
  yy_destructor(8,&yymsp[-1].minor);
}
#line 2353 "queryparser/queryparser_internal.cc"
        break;
      case 26:
#line 1644 "queryparser/queryparser.lemony"
{
    // LOVE BOOLEAN_FILTER(yymsp[0].minor.yy0) is just the same as BOOLEAN_FILTER
    yygotominor.yy12 = yymsp[-2].minor.yy12;
    // We OR filters with the same prefix...
    Query & q = yygotominor.yy12->filter[yymsp[0].minor.yy0->get_filter_group_id()];
    q = Query(Query::OP_OR, q, yymsp[0].minor.yy0->get_query());
    delete yymsp[0].minor.yy0;
  yy_destructor(8,&yymsp[-1].minor);
}
#line 2366 "queryparser/queryparser_internal.cc"
        break;
      case 27:
#line 1659 "queryparser/queryparser.lemony"
{ yygotominor.yy12 = yymsp[0].minor.yy12; }
#line 2371 "queryparser/queryparser_internal.cc"
        break;
      case 28:
#line 1661 "queryparser/queryparser.lemony"
{
    yygotominor.yy12 = new ProbQuery;
    yygotominor.yy12->query = yymsp[0].minor.yy73;
}
#line 2379 "queryparser/queryparser_internal.cc"
        break;
      case 29:
#line 1675 "queryparser/queryparser.lemony"
{
    if (state->is_stopword(yymsp[0].minor.yy0)) {
        yygotominor.yy73 = NULL;
        state->add_to_stoplist(yymsp[0].minor.yy0);
    } else {
        yygotominor.yy73 = new Query(yymsp[0].minor.yy0->get_query_with_auto_synonyms());
    }
    delete yymsp[0].minor.yy0;
}
#line 2392 "queryparser/queryparser_internal.cc"
        break;
      case 31:
#line 1694 "queryparser/queryparser.lemony"
{
    yygotominor.yy73 = new Query(yymsp[0].minor.yy0->get_query_with_auto_synonyms());
    delete yymsp[0].minor.yy0;
}
#line 2400 "queryparser/queryparser_internal.cc"
        break;
      case 33:
#line 1711 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy0->as_wildcarded_query(state); }
#line 2405 "queryparser/queryparser_internal.cc"
        break;
      case 34:
#line 1714 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy0->as_partial_query(state); }
#line 2410 "queryparser/queryparser_internal.cc"
        break;
      case 35:
#line 1717 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[-1].minor.yy27->as_phrase_query();   yy_destructor(20,&yymsp[-2].minor);
  yy_destructor(20,&yymsp[0].minor);
}
#line 2417 "queryparser/queryparser_internal.cc"
        break;
      case 36:
#line 1720 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy27->as_phrase_query(); }
#line 2422 "queryparser/queryparser_internal.cc"
        break;
      case 37:
#line 1722 "queryparser/queryparser.lemony"
{
    yygotominor.yy73 = yymsp[0].minor.yy76->as_group(state);
}
#line 2429 "queryparser/queryparser_internal.cc"
        break;
      case 38:
#line 1727 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy27->as_near_query(); }
#line 2434 "queryparser/queryparser_internal.cc"
        break;
      case 39:
#line 1730 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[0].minor.yy27->as_adj_query(); }
#line 2439 "queryparser/queryparser_internal.cc"
        break;
      case 40:
#line 1733 "queryparser/queryparser.lemony"
{ yygotominor.yy73 = yymsp[-1].minor.yy73;   yy_destructor(21,&yymsp[-2].minor);
  yy_destructor(22,&yymsp[0].minor);
}
#line 2446 "queryparser/queryparser_internal.cc"
        break;
      case 41:
#line 1735 "queryparser/queryparser.lemony"
{
    yygotominor.yy73 = new Query(yymsp[0].minor.yy0->get_query_with_synonyms());
    delete yymsp[0].minor.yy0;
  yy_destructor(11,&yymsp[-1].minor);
}
#line 2455 "queryparser/queryparser_internal.cc"
        break;
      case 42:
#line 1746 "queryparser/queryparser.lemony"
{
    yygotominor.yy27 = new TermList;
    yygotominor.yy27->add_positional_term(yymsp[0].minor.yy0);
}
#line 2463 "queryparser/queryparser_internal.cc"
        break;
      case 43:
      case 45:
#line 1751 "queryparser/queryparser.lemony"
{
    yygotominor.yy27 = yymsp[-1].minor.yy27;
    yygotominor.yy27->add_positional_term(yymsp[0].minor.yy0);
}
#line 2472 "queryparser/queryparser_internal.cc"
        break;
      case 44:
#line 1763 "queryparser/queryparser.lemony"
{
    yygotominor.yy27 = new TermList;
    yygotominor.yy27->add_positional_term(yymsp[-1].minor.yy0);
    yygotominor.yy27->add_positional_term(yymsp[0].minor.yy0);
}
#line 2481 "queryparser/queryparser_internal.cc"
        break;
      case 46:
#line 1780 "queryparser/queryparser.lemony"
{
    yygotominor.yy76 = new TermGroup;
    yygotominor.yy76->add_term(yymsp[-1].minor.yy0);
    yygotominor.yy76->add_term(yymsp[0].minor.yy0);
}
#line 2490 "queryparser/queryparser_internal.cc"
        break;
      case 47:
#line 1786 "queryparser/queryparser.lemony"
{
    yygotominor.yy76 = yymsp[-1].minor.yy76;
    yygotominor.yy76->add_term(yymsp[0].minor.yy0);
}
#line 2498 "queryparser/queryparser_internal.cc"
        break;
      case 48:
      case 50:
#line 1797 "queryparser/queryparser.lemony"
{
    yygotominor.yy27 = new TermList;
    yygotominor.yy27->add_positional_term(yymsp[-2].minor.yy0);
    yygotominor.yy27->add_positional_term(yymsp[0].minor.yy0);
    if (yymsp[-1].minor.yy0) {
        yygotominor.yy27->adjust_window(yymsp[-1].minor.yy0->get_termpos());
        delete yymsp[-1].minor.yy0;
    }
}
#line 2512 "queryparser/queryparser_internal.cc"
        break;
      case 49:
      case 51:
#line 1807 "queryparser/queryparser.lemony"
{
    yygotominor.yy27 = yymsp[-2].minor.yy27;
    yygotominor.yy27->add_positional_term(yymsp[0].minor.yy0);
    if (yymsp[-1].minor.yy0) {
        yygotominor.yy27->adjust_window(yymsp[-1].minor.yy0->get_termpos());
        delete yymsp[-1].minor.yy0;
    }
}
#line 2525 "queryparser/queryparser_internal.cc"
        break;
  }
  yygoto = yyRuleInfo[yyruleno].lhs;
  yysize = yyRuleInfo[yyruleno].nrhs;
  yypParser->yystack.resize(yypParser->yystack.size() - yysize);
  yyact = yy_find_reduce_action(yypParser,yygoto);
  if( yyact < YYNSTATE ){
    yy_shift(yypParser,yyact,yygoto,&yygotominor);
  }else if( yyact == YYNSTATE + YYNRULE + 1 ){
    yy_accept(yypParser);
  }
}

/*
** The following code executes when the parse fails
*/
static void yy_parse_failed(
  yyParser *yypParser           /* The parser */
){
  ParseARG_FETCH;
  DEBUGLINE(QUERYPARSER, "Fail!");
  while( !yypParser->yystack.empty() ) yy_pop_parser_stack(yypParser);
  /* Here code is inserted which will be executed whenever the
  ** parser fails */
#line 1380 "queryparser/queryparser.lemony"

    // If we've not already set an error message, set a default one.
    if (!state->error) state->error = "parse error";
#line 2555 "queryparser/queryparser_internal.cc"
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}

/*
** The following code executes when a syntax error first occurs.
*/
static void yy_syntax_error(
  yyParser *yypParser,           /* The parser */
  int yymajor,                   /* The major type of the error token */
  YYMINORTYPE yyminor            /* The minor type of the error token */
){
  ParseARG_FETCH;
  (void)yymajor;
  (void)yyminor;
#define TOKEN (yyminor.yy0)
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}

/*
** The following is executed when the parser accepts
*/
static void yy_accept(
  yyParser *yypParser           /* The parser */
){
  ParseARG_FETCH;
  DEBUGLINE(QUERYPARSER, "Accept!");
  while( !yypParser->yystack.empty() ) yy_pop_parser_stack(yypParser);
  /* Here code is inserted which will be executed whenever the
  ** parser accepts */
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}

/* The main parser program.
** The first argument is a pointer to a structure obtained from
** "ParseAlloc" which describes the current state of the parser.
** The second argument is the major token number.  The third is
** the minor token.  The fourth optional argument is whatever the
** user wants (and specified in the grammar) and is available for
** use by the action routines.
**
** Inputs:
** <ul>
** <li> A pointer to the parser (an opaque structure.)
** <li> The major token number.
** <li> The minor token number.
** <li> An option argument of a grammar-specified type.
** </ul>
**
** Outputs:
** None.
*/
static void Parse(
  yyParser *yypParser,         /* The parser */
  int yymajor,                 /* The major token code number */
  ParseTOKENTYPE yyminor       /* The value for the token */
  ParseARG_PDECL               /* Optional %extra_argument parameter */
){
  YYMINORTYPE yyminorunion;
  int yyact;            /* The parser action. */
  int yyendofinput;     /* True if we are at the end of input */
  int yyerrorhit = 0;   /* True if yymajor has invoked an error */

  /* (re)initialize the parser, if necessary */
  if( yypParser->yystack.empty() ){
    if( yymajor==0 ) return;
    yypParser->yystack.push_back(yyStackEntry());
    yypParser->yyerrcnt = -1;
  }
  yyminorunion.yy0 = yyminor;
  yyendofinput = (yymajor==0);
  ParseARG_STORE;

  DEBUGLINE(QUERYPARSER, "Input " << ParseTokenName(yymajor) << " " <<
            (yyminor ? yyminor->name : "<<null>>"));

  do{
    yyact = yy_find_shift_action(yypParser,yymajor);
    if( yyact<YYNSTATE ){
      yy_shift(yypParser,yyact,yymajor,&yyminorunion);
      yypParser->yyerrcnt--;
      if( yyendofinput && !yypParser->yystack.empty() ){
        yymajor = 0;
      }else{
        yymajor = YYNOCODE;
      }
    }else if( yyact < YYNSTATE + YYNRULE ){
      yy_reduce(yypParser,yyact-YYNSTATE);
    }else if( yyact == YY_ERROR_ACTION ){
      int yymx;
      DEBUGLINE(QUERYPARSER, "Syntax Error!");
#ifdef YYERRORSYMBOL
      /* A syntax error has occurred.
      ** The response to an error depends upon whether or not the
      ** grammar defines an error token "ERROR".  
      **
      ** This is what we do if the grammar does define ERROR:
      **
      **  * Call the %syntax_error function.
      **
      **  * Begin popping the stack until we enter a state where
      **    it is legal to shift the error symbol, then shift
      **    the error symbol.
      **
      **  * Set the error count to three.
      **
      **  * Begin accepting and shifting new tokens.  No new error
      **    processing will occur until three tokens have been
      **    shifted successfully.
      **
      */
      if( yypParser->yyerrcnt<0 ){
        yy_syntax_error(yypParser,yymajor,yyminorunion);
      }
      yymx = yypParser->yystack.back().major;
      if( yymx==YYERRORSYMBOL || yyerrorhit ){
        DEBUGLINE(QUERYPARSER, "Discard input token " << ParseTokenName(yymajor));
        yy_destructor((YYCODETYPE)yymajor,&yyminorunion);
        yymajor = YYNOCODE;
      }else{
         while(
          !yypParser->yystack.empty() &&
          yymx != YYERRORSYMBOL &&
          (yyact = yy_find_shift_action(yypParser,YYERRORSYMBOL)) >= YYNSTATE
        ){
          yy_pop_parser_stack(yypParser);
        }
        if( yypParser->yystack.empty() || yymajor==0 ){
          yy_destructor((YYCODETYPE)yymajor,&yyminorunion);
          yy_parse_failed(yypParser);
          yymajor = YYNOCODE;
        }else if( yymx!=YYERRORSYMBOL ){
          YYMINORTYPE u2;
          u2.YYERRSYMDT = 0;
          yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2);
        }
      }
      yypParser->yyerrcnt = 3;
      yyerrorhit = 1;
#else  /* YYERRORSYMBOL is not defined */
      /* This is what we do if the grammar does not define ERROR:
      **
      **  * Report an error message, and throw away the input token.
      **
      **  * If the input token is $, then fail the parse.
      **
      ** As before, subsequent error messages are suppressed until
      ** three input tokens have been successfully shifted.
      */
      if( yypParser->yyerrcnt<=0 ){
        yy_syntax_error(yypParser,yymajor,yyminorunion);
      }
      yypParser->yyerrcnt = 3;
      yy_destructor((YYCODETYPE)yymajor,&yyminorunion);
      if( yyendofinput ){
        yy_parse_failed(yypParser);
      }
      yymajor = YYNOCODE;
#endif
    }else{
      yy_accept(yypParser);
      yymajor = YYNOCODE;
    }
  }while( yymajor!=YYNOCODE && !yypParser->yystack.empty() );
  return;
}

// Select C++ syntax highlighting in vim editor: vim: syntax=cpp

---