+
+// LINQ
+
+query_expression
+ : first_from_clause
+ {
+ ++lexer.query_parsing;
+ }
+ query_body
+ {
+ if (--lexer.query_parsing == 1)
+ lexer.query_parsing = 0;
+
+ Linq.AQueryClause from = $1 as Linq.AQueryClause;
+
+ from.Tail.Next = (Linq.AQueryClause)$3;
+ $$ = from;
+
+ current_block.SetEndLocation (lexer.Location);
+ current_block = current_block.Parent;
+ }
+ ;
+
+first_from_clause
+ : FROM IDENTIFIER IN expression
+ {
+ current_block = new Linq.QueryBlock (current_block, GetLocation ($1));
+ LocatedToken lt = (LocatedToken) $2;
+
+ current_block.AddVariable (Linq.ImplicitQueryParameter.ImplicitType.Instance, lt.Value, lt.Location);
+ $$ = new Linq.QueryExpression (lt, new Linq.QueryStartClause ((Expression)$4));
+ }
+ | FROM type IDENTIFIER IN expression
+ {
+ current_block = new Linq.QueryBlock (current_block, GetLocation ($1));
+ LocatedToken lt = (LocatedToken) $3;
+
+ Expression type = (Expression)$2;
+ current_block.AddVariable (type, lt.Value, lt.Location);
+ $$ = new Linq.QueryExpression (lt, new Linq.Cast (type, (Expression)$5));
+ }
+ ;
+
+from_clause
+ : FROM IDENTIFIER IN expression
+ {
+ LocatedToken lt = (LocatedToken) $2;
+
+ current_block.AddVariable (Linq.ImplicitQueryParameter.ImplicitType.Instance,
+ lt.Value, lt.Location);
+
+ $$ = new Linq.SelectMany (lt, (Expression)$4);
+ }
+ | FROM type IDENTIFIER IN expression
+ {
+ LocatedToken lt = (LocatedToken) $3;
+
+ Expression type = (Expression)$2;
+ current_block.AddVariable (type, lt.Value, lt.Location);
+ $$ = new Linq.SelectMany (lt, new Linq.Cast (type, (Expression)$5));
+ }
+ ;
+
+query_body
+ : opt_query_body_clauses select_or_group_clause opt_query_continuation
+ {
+ Linq.AQueryClause head = (Linq.AQueryClause)$2;
+
+ if ($3 != null)
+ head.Next = (Linq.AQueryClause)$3;
+
+ if ($1 != null) {
+ Linq.AQueryClause clause = (Linq.AQueryClause)$1;
+ clause.Tail.Next = head;
+ head = clause;
+ }
+
+ $$ = head;
+ }
+ ;
+
+select_or_group_clause
+ : SELECT expression
+ {
+ $$ = new Linq.Select ((Expression)$2, GetLocation ($1));
+ }
+ | GROUP expression BY expression
+ {
+ $$ = new Linq.GroupBy ((Expression)$2, (Expression)$4, GetLocation ($1));
+ }
+ ;
+
+opt_query_body_clauses
+ : /* empty */
+ | query_body_clauses
+ ;
+
+query_body_clauses
+ : query_body_clause
+ | query_body_clauses query_body_clause
+ {
+ ((Linq.AQueryClause)$1).Tail.Next = (Linq.AQueryClause)$2;
+ $$ = $1;
+ }
+ ;
+
+query_body_clause
+ : from_clause
+ | let_clause
+ | where_clause
+ | join_clause
+ | orderby_clause
+ ;
+
+let_clause
+ : LET IDENTIFIER ASSIGN expression
+ {
+ LocatedToken lt = (LocatedToken) $2;
+ current_block.AddVariable (Linq.ImplicitQueryParameter.ImplicitType.Instance,
+ lt.Value, lt.Location);
+ $$ = new Linq.Let (lt, (Expression)$4, GetLocation ($1));
+ }
+ ;
+
+where_clause
+ : WHERE boolean_expression
+ {
+ $$ = new Linq.Where ((Expression)$2, GetLocation ($1));
+ }
+ ;
+
+join_clause
+ : JOIN IDENTIFIER IN expression ON expression EQUALS expression opt_join_into
+ {
+ Location loc = GetLocation ($1);
+ LocatedToken lt = (LocatedToken) $2;
+ current_block.AddVariable (Linq.ImplicitQueryParameter.ImplicitType.Instance,
+ lt.Value, lt.Location);
+
+ if ($9 == null) {
+ $$ = new Linq.Join (lt, (Expression)$4, (Expression)$6,
+ (Expression)$8, loc);
+ } else {
+ LocatedToken lt_into = (LocatedToken) $9;
+ $$ = new Linq.GroupJoin (lt, (Expression)$4, (Expression)$6,
+ (Expression)$8, lt_into, loc);
+ }
+ }
+ | JOIN type IDENTIFIER IN expression ON expression EQUALS expression opt_join_into
+ {
+ Location loc = GetLocation ($1);
+ LocatedToken lt = (LocatedToken) $3;
+ current_block.AddVariable ((Expression)$2, lt.Value, lt.Location);
+
+ Linq.Cast cast = new Linq.Cast ((Expression)$2, (Expression)$5);
+ if ($10 == null) {
+ $$ = new Linq.Join (lt, cast, (Expression)$7,
+ (Expression)$9, loc);
+ } else {
+ LocatedToken lt_into = (LocatedToken) $10;
+ $$ = new Linq.GroupJoin (lt, cast, (Expression)$7,
+ (Expression)$9, lt_into, loc);
+ }
+ }
+ ;
+
+opt_join_into
+ : /* empty */
+ | INTO IDENTIFIER
+ {
+ $$ = $2;
+ }
+ ;
+
+orderby_clause
+ : ORDERBY orderings
+ {
+ $$ = $2;
+ }
+ ;
+
+orderings
+ : order_by
+ | order_by COMMA orderings_then_by
+ {
+ ((Linq.AQueryClause)$1).Next = (Linq.AQueryClause)$3;
+ $$ = $1;
+ }
+ ;
+
+orderings_then_by
+ : then_by
+ {
+ $$ = $1;
+ }
+ | orderings_then_by COMMA then_by
+ {
+ ((Linq.AQueryClause)$1).Tail.Next = (Linq.AQueryClause)$3;
+ $$ = $1;
+ }
+ ;
+
+order_by
+ : expression
+ {
+ $$ = new Linq.OrderByAscending ((Expression)$1);
+ }
+ | expression ASCENDING
+ {
+ $$ = new Linq.OrderByAscending ((Expression)$1);
+ }
+ | expression DESCENDING
+ {
+ $$ = new Linq.OrderByDescending ((Expression)$1);
+ }
+ ;
+
+then_by
+ : expression
+ {
+ $$ = new Linq.ThenByAscending ((Expression)$1);
+ }
+ | expression ASCENDING
+ {
+ $$ = new Linq.ThenByAscending ((Expression)$1);
+ }
+ | expression DESCENDING
+ {
+ $$ = new Linq.ThenByDescending ((Expression)$1);
+ }
+ ;
+
+
+opt_query_continuation
+ : /* empty */
+ | INTO IDENTIFIER
+ {
+ // query continuation block is not linked with query block but with block
+ // before. This means each query can use same range variable names for
+ // different identifiers.
+
+ current_block.SetEndLocation (GetLocation ($1));
+ current_block = current_block.Parent;
+ current_block = new Linq.QueryBlock (current_block, GetLocation ($1));
+
+ LocatedToken lt = (LocatedToken) $2;
+ current_block.AddVariable (Linq.ImplicitQueryParameter.ImplicitType.Instance,
+ lt.Value, lt.Location);
+ }
+ query_body
+ {
+ $$ = new Linq.QueryExpression ((LocatedToken) $2,
+ (Linq.AQueryClause)$4);
+ }
+ ;
+