Change the notation for calling functions with named parameters from

"val AS name" to "name := val", as per recent discussion.

This patch catches everything in the original named-parameters patch,
but I'm not certain that no other dependencies snuck in later (grepping
the source tree for all uses of AS soon proved unworkable).

In passing I note that we've dropped the ball at least once on keeping
ecpg's lexer (as opposed to parser) in sync with the backend.  It would
be a good idea to go through all of pgc.l and see if it's in sync now.
I didn't attempt that at the moment.

Author: tglsfdc

doc/src/sgml/syntax.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.144 2010/05/27 18:23:47 petere Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.145 2010/05/30 18:10:40 tgl Exp $ -->
 
 <chapter id="sql-syntax">
  <title>SQL Syntax</title>
@@ -2285,10 +2285,11 @@ SELECT concat_lower_or_upper('Hello', 'World');
     </indexterm>
 
     <para>
-     In named notation, each argument's name is specified using the
-     <literal>AS</literal> keyword.  For example:
+     In named notation, each argument's name is specified using
+     <literal>:=</literal> to separate it from the argument expression.
+     For example:
 <screen>
-SELECT concat_lower_or_upper('Hello' AS a, 'World' AS b);
+SELECT concat_lower_or_upper(a := 'Hello', b := 'World');
  concat_lower_or_upper 
 -----------------------
  hello world
@@ -2299,13 +2300,13 @@ SELECT concat_lower_or_upper('Hello' AS a, 'World' AS b);
      using named notation is that the arguments may be specified in any
      order, for example:
 <screen>
-SELECT concat_lower_or_upper('Hello' AS a, 'World' AS b, true AS uppercase);
+SELECT concat_lower_or_upper(a := 'Hello', b := 'World', uppercase := true);
  concat_lower_or_upper 
 -----------------------
  HELLO WORLD
 (1 row)
 
-SELECT concat_lower_or_upper('Hello' AS a, true AS uppercase, 'World' AS b);
+SELECT concat_lower_or_upper(a := 'Hello', uppercase := true, b := 'World');
  concat_lower_or_upper 
 -----------------------
  HELLO WORLD
@@ -2327,7 +2328,7 @@ SELECT concat_lower_or_upper('Hello' AS a, true AS uppercase, 'World' AS b);
     already mentioned, named arguments cannot precede positional arguments.
     For example:
 <screen>
-SELECT concat_lower_or_upper('Hello', 'World', true AS uppercase);
+SELECT concat_lower_or_upper('Hello', 'World', uppercase := true);
  concat_lower_or_upper 
 -----------------------
  HELLO WORLD

doc/src/sgml/xfunc.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.148 2010/05/16 04:35:04 rhaas Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.149 2010/05/30 18:10:40 tgl Exp $ -->
 
  <sect1 id="xfunc">
   <title>User-Defined Functions</title>
@@ -705,14 +705,14 @@ SELECT mleast(VARIADIC ARRAY[10, -1, 5, 4.4]);
      <literal>VARIADIC</>.  For example, this will work:
 
 <screen>
-SELECT mleast(VARIADIC ARRAY[10, -1, 5, 4.4] AS arr);
+SELECT mleast(VARIADIC arr := ARRAY[10, -1, 5, 4.4]);
 </screen>
 
      but not these:
 
 <screen>
-SELECT mleast(10 AS arr);
-SELECT mleast(ARRAY[10, -1, 5, 4.4] AS arr);
+SELECT mleast(arr := 10);
+SELECT mleast(arr := ARRAY[10, -1, 5, 4.4]);
 </screen>
     </para>
    </sect2>

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.711 2010/02/23 22:51:42 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.712 2010/05/30 18:10:40 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -444,8 +444,8 @@ static TypeName *TableFuncTypeName(List *columns);
  * 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 and COLON_EQUALS are unused in the core SQL grammar, and so will
- * always provoke parse errors.  They are needed by PL/pgsql.
+ * 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
@@ -10212,13 +10212,13 @@ func_arg_expr:  a_expr
 				{
 					$$ = $1;
 				}
-			| a_expr AS param_name
+			| param_name COLON_EQUALS a_expr
 				{
 					NamedArgExpr *na = makeNode(NamedArgExpr);
-					na->arg = (Expr *) $1;
-					na->name = $3;
+					na->name = $1;
+					na->arg = (Expr *) $3;
 					na->argnumber = -1;		/* until determined */
-					na->location = @3;
+					na->location = @1;
 					$$ = (Node *) na;
 				}
 		;
@@ -10698,7 +10698,7 @@ AexprConst: Iconst
 						if (IsA(arg, NamedArgExpr))
 							ereport(ERROR,
 								    (errcode(ERRCODE_SYNTAX_ERROR),
-								     errmsg("type modifier cannot have AS name"),
+								     errmsg("type modifier cannot have parameter name"),
 								     parser_errposition(arg->location)));
 					}
 					t->typmods = $3;

src/backend/parser/parse_func.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_func.c,v 1.223 2010/03/17 16:52:38 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_func.c,v 1.224 2010/05/30 18:10:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1386,12 +1386,12 @@ funcname_signature_string(const char *funcname, int nargs,
 	{
 		if (i)
 			appendStringInfoString(&argbuf, ", ");
-		appendStringInfoString(&argbuf, format_type_be(argtypes[i]));
 		if (i >= numposargs)
 		{
-			appendStringInfo(&argbuf, " AS %s", (char *) lfirst(lc));
+			appendStringInfo(&argbuf, "%s := ", (char *) lfirst(lc));
 			lc = lnext(lc);
 		}
+		appendStringInfoString(&argbuf, format_type_be(argtypes[i]));
 	}
 
 	appendStringInfoChar(&argbuf, ')');

src/backend/parser/scan.l

@@ -24,7 +24,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/scan.l,v 1.166 2010/01/16 17:39:55 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/scan.l,v 1.167 2010/05/30 18:10:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -317,8 +317,6 @@ ident_cont		[A-Za-z\200-\377_0-9\$]
 identifier		{ident_start}{ident_cont}*
 
 typecast		"::"
-
-/* these two token types are used by PL/pgsql, though not in core SQL */
 dot_dot			\.\.
 colon_equals	":="
 

src/backend/utils/adt/ruleutils.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.325 2010/02/26 02:01:09 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.326 2010/05/30 18:10:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -4537,8 +4537,8 @@ get_rule_expr(Node *node, deparse_context *context,
 			{
 				NamedArgExpr *na = (NamedArgExpr *) node;
 
+				appendStringInfo(buf, "%s := ", quote_identifier(na->name));
 				get_rule_expr((Node *) na->arg, context, showimplicit);
-				appendStringInfo(buf, " AS %s", quote_identifier(na->name));
 			}
 			break;
 

src/bin/psql/psqlscan.l

@@ -33,7 +33,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/bin/psql/psqlscan.l,v 1.33 2010/05/05 22:18:56 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/bin/psql/psqlscan.l,v 1.34 2010/05/30 18:10:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -345,8 +345,6 @@ ident_cont		[A-Za-z\200-\377_0-9\$]
 identifier		{ident_start}{ident_cont}*
 
 typecast		"::"
-
-/* these two token types are used by PL/pgsql, though not in core SQL */
 dot_dot			\.\.
 colon_equals	":="
 

src/interfaces/ecpg/preproc/parse.pl

@@ -1,5 +1,5 @@
 #!/usr/bin/perl
-# $PostgreSQL: pgsql/src/interfaces/ecpg/preproc/parse.pl,v 1.7 2010/01/02 16:58:11 momjian Exp $
+# $PostgreSQL: pgsql/src/interfaces/ecpg/preproc/parse.pl,v 1.8 2010/05/30 18:10:41 tgl Exp $
 # parser generater for ecpg
 # call with backend parser as stdin
 #
@@ -41,6 +41,8 @@
 $replace_string{'NULLS_FIRST'} = 'nulls first';
 $replace_string{'NULLS_LAST'} = 'nulls last';
 $replace_string{'TYPECAST'} = '::';
+$replace_string{'DOT_DOT'} = '..';
+$replace_string{'COLON_EQUALS'} = ':=';
 
 # specific replace_types for specific non-terminals - never include the ':'
 # ECPG-only replace_types are defined in ecpg-replace_types

src/interfaces/ecpg/preproc/pgc.l

@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/interfaces/ecpg/preproc/pgc.l,v 1.173 2010/03/21 10:49:51 meskes Exp $
+ *	  $PostgreSQL: pgsql/src/interfaces/ecpg/preproc/pgc.l,v 1.174 2010/05/30 18:10:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -230,6 +230,8 @@ identifier		{ident_start}{ident_cont}*
 
 array			({ident_cont}|{whitespace}|[\[\]\+\-\*\%\/\(\)\>\.])*
 typecast		"::"
+dot_dot			\.\.
+colon_equals	":="
 
 /*
  * "self" is the set of chars that should be returned as single-character
@@ -595,6 +597,8 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})(.*\\{space})*.
 					}
 <xdc>{xdcinside}	{ addlit(yytext, yyleng); }
 <SQL>{typecast}		{ return TYPECAST; }
+<SQL>{dot_dot}		{ return DOT_DOT; }
+<SQL>{colon_equals}	{ return COLON_EQUALS; }
 <SQL>{informix_special}	{
 			  /* are we simulating Informix? */
 				if (INFORMIX_MODE)