parse_coerce.h

/*-------------------------------------------------------------------------
 *
 * parse_coerce.h
 *	Routines for type coercion.
 *
 *
 * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * $Id: parse_coerce.h,v 1.48 2002/10/24 22:09:00 tgl Exp $
 *
 *-------------------------------------------------------------------------
 */
#ifndef PARSE_COERCE_H
#define PARSE_COERCE_H

#include "catalog/pg_type.h"
#include "parser/parse_node.h"

typedef enum CATEGORY
{
	INVALID_TYPE,
	UNKNOWN_TYPE,
	BOOLEAN_TYPE,
	STRING_TYPE,
	BITSTRING_TYPE,
	NUMERIC_TYPE,
	DATETIME_TYPE,
	TIMESPAN_TYPE,
	GEOMETRIC_TYPE,
	NETWORK_TYPE,
	USER_TYPE
} CATEGORY;


extern bool IsBinaryCoercible(Oid srctype, Oid targettype);
extern bool IsPreferredType(CATEGORY category, Oid type);
extern CATEGORY TypeCategory(Oid type);

extern Node *coerce_to_target_type(Node *expr, Oid exprtype,
								   Oid targettype, int32 targettypmod,
								   CoercionContext ccontext,
								   CoercionForm cformat);
extern bool can_coerce_type(int nargs, Oid *input_typeids, Oid *target_typeids,
							CoercionContext ccontext);
extern Node *coerce_type(Node *node, Oid inputTypeId, Oid targetTypeId,
						 CoercionContext ccontext, CoercionForm cformat);
extern Node *coerce_type_constraints(Node *arg, Oid typeId,
									 CoercionForm cformat);

extern Node *coerce_to_boolean(Node *node, const char *constructName);

extern Oid	select_common_type(List *typeids, const char *context);
extern Node *coerce_to_common_type(Node *node, Oid targetTypeId,
					  const char *context);

extern bool find_coercion_pathway(Oid targetTypeId, Oid sourceTypeId,
								  CoercionContext ccontext,
								  Oid *funcid);
extern Oid	find_typmod_coercion_function(Oid typeId, int *nargs);

#endif   /* PARSE_COERCE_H */