Added syntactic sugar for record expressions and record patterns:

{ lbl } stands for { lbl = lbl }.


git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@9324 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Changes

@@ -3,6 +3,10 @@ Objective Caml 3.12.0:
 
 (Changes that can break existing programs are marked with a "*"  )
 
+Language features:
+- Shorthand notation for records: in expressions and patterns,
+    { lbl } stands for { lbl = lbl } and { M.lbl } for { M.lbl = lbl }
+
 Compilers and toplevel:
 - Added option '-no-app-funct' to turn applicative functors off.
   This option can help working around mysterious type incompatibilities

parsing/longident.ml

@@ -24,6 +24,11 @@ let rec flat accu = function
 
 let flatten lid = flat [] lid
 
+let last = function
+    Lident s -> s
+  | Ldot(lid, s) -> s
+  | Lapply(l1, l2) -> Misc.fatal_error "Longident.last"
+
 let rec split_at_dots s pos =
   try
     let dot = String.index_from s pos '.' in

parsing/longident.mli

@@ -20,4 +20,5 @@ type t =
   | Lapply of t * t
 
 val flatten: t -> string list
+val last: t -> string
 val parse: string -> t

parsing/parser.mly

@@ -191,6 +191,12 @@ let lapply p1 p2 =
   then Lapply(p1, p2)
   else raise (Syntaxerr.Error(Syntaxerr.Applicative_path (symbol_rloc())))
 
+let exp_of_label lbl =
+  mkexp (Pexp_ident(Lident(Longident.last lbl)))
+
+let pat_of_label lbl =
+  mkpat (Ppat_var(Longident.last lbl))
+
 %}
 
 /* Tokens */
@@ -1043,8 +1049,12 @@ record_expr:
 lbl_expr_list:
     label_longident EQUAL expr
       { [$1,$3] }
+  | label_longident
+      { [$1, exp_of_label $1] }
   | lbl_expr_list SEMI label_longident EQUAL expr
       { ($3, $5) :: $1 }
+  | lbl_expr_list SEMI label_longident
+      { ($3, exp_of_label $3) :: $1 }
 ;
 field_expr_list:
     label EQUAL expr
@@ -1137,7 +1147,9 @@ pattern_semi_list:
 ;
 lbl_pattern_list:
     label_longident EQUAL pattern               { [($1, $3)] }
+  | label_longident                             { [($1, pat_of_label $1)] }
   | lbl_pattern_list SEMI label_longident EQUAL pattern { ($3, $5) :: $1 }
+  | lbl_pattern_list SEMI label_longident       { ($3, pat_of_label $3) :: $1 }
 ;
 
 /* Primitive declarations */

parsing/parsetree.mli

@@ -46,7 +46,7 @@ and row_field =
     Rtag of label * bool * core_type list
   | Rinherit of core_type
 
-(* XXX Type expressions for the class language *)
+(* Type expressions for the class language *)
 
 type 'a class_infos =
   { pci_virt: virtual_flag;