%{
{{{ GRAMMAR_HEADER }}}
%}
#line 5 "third_party/libpg_query/grammar/grammar.y"
%pure-parser
%expect 0
%name-prefix="base_yy"
%locations

%parse-param {core_yyscan_t yyscanner}
%lex-param   {core_yyscan_t yyscanner}

%union
{
	core_YYSTYPE		core_yystype;
	/* these fields must match core_YYSTYPE: */
	int					ival;
	char				*str;
	const char			*keyword;
	const char          *conststr;

	char				chr;
	bool				boolean;
	PGJoinType			jtype;
	PGDropBehavior		dbehavior;
	PGOnCommitAction		oncommit;
	PGOnCreateConflict		oncreateconflict;
	PGList				*list;
	PGNode				*node;
	PGValue				*value;
	PGObjectType			objtype;
	PGTypeName			*typnam;
	PGObjectWithArgs		*objwithargs;
	PGDefElem				*defelt;
	PGSortBy				*sortby;
	PGWindowDef			*windef;
	PGJoinExpr			*jexpr;
	PGIndexElem			*ielem;
	PGAlias				*alias;
	PGRangeVar			*range;
	PGIntoClause			*into;
	PGCTEMaterialize			ctematerialize;
	PGWithClause			*with;
	PGInferClause			*infer;
	PGOnConflictClause	*onconflict;
	PGOnConflictActionAlias onconflictshorthand;
	PGAIndices			*aind;
	PGResTarget			*target;
	PGInsertStmt			*istmt;
	PGVariableSetStmt		*vsetstmt;
	PGOverridingKind       override;
	PGSortByDir            sortorder;
	PGSortByNulls          nullorder;
	PGIgnoreNulls          ignorenulls;
	PGConstrType           constr;
	PGLockClauseStrength lockstrength;
	PGLockWaitPolicy lockwaitpolicy;
	PGSubLinkType subquerytype;
	PGViewCheckOption viewcheckoption;
	PGInsertColumnOrder bynameorposition;
	PGLoadInstallType loadinstalltype;
	PGTransactionStmtType transactiontype;
}

%type <node> stmt
%type <list> stmtblock
%type <list> stmtmulti
{{{ TYPES }}}

/*
 * Non-keyword token types.  These are hard-wired into the "flex" lexer.
 * They must be listed first so that their numeric codes do not depend on
 * the set of keywords.  PL/pgSQL depends on this so that it can share the
 * same lexer.  If you add/change tokens here, fix PL/pgSQL to match!
 *
 * DOT_DOT is unused in the core SQL grammar, and so will always provoke
 * parse errors.  It is needed by PL/pgSQL.
 */
%token <str>	IDENT FCONST SCONST BCONST XCONST Op
%token <ival>	ICONST PARAM
%token			TYPECAST DOT_DOT COLON_EQUALS EQUALS_GREATER INTEGER_DIVISION POWER_OF LAMBDA_ARROW DOUBLE_ARROW
%token			LESS_EQUALS GREATER_EQUALS NOT_EQUALS

/*
 * If you want to make any keyword changes, update the keyword table in
 * src/include/parser/kwlist.h and add new keywords to the appropriate one
 * of the reserved-or-not-so-reserved keyword lists, below; search
 * this file for "Keyword category lists".
 */

/* ordinary key words in alphabetical order */
{{{ KEYWORDS }}}

/*
 * The grammar thinks these are keywords, but they are not in the kwlist.h
 * list and so can never be entered directly.  The filter in parser.c
 * creates these tokens when required (based on looking one token ahead).
 *
 * NOT_LA exists so that productions such as NOT LIKE can be given the same
 * precedence as LIKE; otherwise they'd effectively have the same precedence
 * as NOT, at least with respect to their left-hand subexpression.
 * NULLS_LA and WITH_LA are needed to make the grammar LALR(1).
 */
%token		NOT_LA NULLS_LA WITH_LA


/* Precedence: lowest to highest */
%nonassoc	SET				/* see */
%left		UNION EXCEPT
%left		INTERSECT
%left		LAMBDA_ARROW DOUBLE_ARROW
%left		OR
%left		AND
%right		NOT
%nonassoc	IS ISNULL NOTNULL	/* IS sets precedence for IS NULL, etc */
%nonassoc	'<' '>' '=' LESS_EQUALS GREATER_EQUALS NOT_EQUALS
%nonassoc	BETWEEN IN_P GLOB LIKE ILIKE SIMILAR NOT_LA
%nonassoc	ESCAPE			/* ESCAPE must be just above LIKE/ILIKE/SIMILAR */
%left		POSTFIXOP		/* dummy for postfix Op rules */
/*
 * To support target_el without AS, we must give IDENT an explicit priority
 * between POSTFIXOP and Op.  We can safely assign the same priority to
 * various unreserved keywords as needed to resolve ambiguities (this can't
 * have any bad effects since obviously the keywords will still behave the
 * same as if they weren't keywords).  We need to do this for PARTITION,
 * RANGE, ROWS to support opt_existing_window_name; and for RANGE, ROWS
 * so that they can follow a_expr without creating postfix-operator problems;
 * for GENERATED so that it can follow b_expr;
 * and for NULL so that it can follow b_expr in without creating
 * postfix-operator problems.
 *
 * To support CUBE and ROLLUP in GROUP BY without reserving them, we give them
 * an explicit priority lower than '(', so that a rule with CUBE '(' will shift
 * rather than reducing a conflicting rule that takes CUBE as a function name.
 * Using the same precedence as IDENT seems right for the reasons given above.
 *
 * The frame_bound productions UNBOUNDED PRECEDING and UNBOUNDED FOLLOWING
 * are even messier: since UNBOUNDED is an unreserved keyword (per spec!),
 * there is no principled way to distinguish these from the productions
 * a_expr PRECEDING/FOLLOWING.  We hack this up by giving UNBOUNDED slightly
 * lower precedence than PRECEDING and FOLLOWING.  At present this doesn't
 * appear to cause UNBOUNDED to be treated differently from other unreserved
 * keywords anywhere else in the grammar, but it's definitely risky.  We can
 * blame any funny behavior of UNBOUNDED on the SQL standard, though.
 */
%nonassoc	UNBOUNDED		/* ideally should have same precedence as IDENT */
%nonassoc	IDENT GENERATED NULL_P PARTITION RANGE ROWS GROUPS PRECEDING FOLLOWING CUBE ROLLUP ENUM_P
%left		Op OPERATOR		/* multi-character ops and user-defined operators */
%left		'+' '-'
%left		'*' '/' '%' INTEGER_DIVISION
%left		'^' POWER_OF
/* Unary Operators */
%left		AT				/* sets precedence for AT TIME ZONE */
%left		COLLATE
%right		UMINUS
%left		'[' ']'
%left		'(' ')'
%left		TYPECAST
%left		'.'
/*
 * These might seem to be low-precedence, but actually they are not part
 * of the arithmetic hierarchy at all in their use as JOIN operators.
 * We make them high-precedence to support their use as function names.
 * They wouldn't be given a precedence at all, were it not that we need
 * left-associativity among the JOIN rules themselves.
 */
%left		JOIN CROSS LEFT FULL RIGHT INNER_P NATURAL POSITIONAL PIVOT UNPIVOT ANTI SEMI ASOF
/* kluge to keep from causing shift/reduce conflicts */
%right		PRESERVE STRIP_P IGNORE_P RESPECT_P

%%

/*
 *	The target production for the whole parse.
 */
stmtblock:	stmtmulti
			{
				pg_yyget_extra(yyscanner)->parsetree = $1;
			}
		;

/*
 * At top level, we wrap each stmt with a PGRawStmt node carrying start location
 * and length of the stmt's text.  Notice that the start loc/len are driven
 * entirely from semicolon locations (@2).  It would seem natural to use
 * @1 or @3 to get the true start location of a stmt, but that doesn't work
 * for statements that can start with empty nonterminals (opt_with_clause is
 * the main offender here); as noted in the comments for YYLLOC_DEFAULT,
 * we'd get -1 for the location in such cases.
 * We also take care to discard empty statements entirely.
 */
stmtmulti:	stmtmulti ';' stmt
				{
					if ($1 != NIL)
					{
						/* update length of previous stmt */
						updateRawStmtEnd(llast_node(PGRawStmt, $1), @2);
					}
					if ($3 != NULL)
						$$ = lappend($1, makeRawStmt($3, @2 + 1));
					else
						$$ = $1;
				}
			| stmt
				{
					if ($1 != NULL)
						$$ = list_make1(makeRawStmt($1, 0));
					else
						$$ = NIL;
				}
		;

{{{ STATEMENTS }}}

{{{ GRAMMAR RULES }}}

{{{ KEYWORD_DEFINITIONS }}}

%%

{{{ GRAMMAR_SOURCE }}}
