Extend pg_cast castimplicit column to a three-way value; this allows us

to be flexible about assignment casts without introducing ambiguity in
operator/function resolution.  Introduce a well-defined promotion hierarchy
for numeric datatypes (int2->int4->int8->numeric->float4->float8).
Change make_const to initially label numeric literals as int4, int8, or
numeric (never float8 anymore).
Explicitly mark Func and RelabelType nodes to indicate whether they came
from a function call, explicit cast, or implicit cast; use this to do
reverse-listing more accurately and without so many heuristics.
Explicit casts to char, varchar, bit, varbit will truncate or pad without
raising an error (the pre-7.2 behavior), while assigning to a column without
any explicit cast will still raise an error for wrong-length data like 7.3.
This more nearly follows the SQL spec than 7.2 behavior (we should be
reporting a 'completion condition' in the explicit-cast cases, but we have
no mechanism for that, so just do silent truncation).
Fix some problems with enforcement of typmod for array elements;
it didn't work at all in 'UPDATE ... SET array[n] = foo', for example.
Provide a generalized array_length_coerce() function to replace the
specialized per-array-type functions that used to be needed (and were
missing for NUMERIC as well as all the datetime types).
Add missing conversions int8<->float4, text<->numeric, oid<->int8.
initdb forced.

src/include/parser/parse_target.h

@@ -1,13 +1,13 @@
 /*-------------------------------------------------------------------------
  *
  * parse_target.h
- *
+ *	  handle target lists
  *
  *
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parse_target.h,v 1.26 2002/09/04 20:31:45 momjian Exp $
+ * $Id: parse_target.h,v 1.27 2002/09/18 21:35:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -16,6 +16,7 @@
 
 #include "parser/parse_node.h"
 
+
 extern List *transformTargetList(ParseState *pstate, List *targetlist);
 extern TargetEntry *transformTargetEntry(ParseState *pstate,
 					 Node *node, Node *expr,
@@ -23,9 +24,6 @@ extern TargetEntry *transformTargetEntry(ParseState *pstate,
 extern void updateTargetListEntry(ParseState *pstate, TargetEntry *tle,
 					  char *colname, int attrno,
 					  List *indirection);
-extern Node *CoerceTargetExpr(ParseState *pstate, Node *expr,
-				 Oid type_id, Oid attrtype, int32 attrtypmod,
-				 bool isExplicit);
 extern List *checkInsertTargets(ParseState *pstate, List *cols,
 				   List **attrnos);