/*
** Copyright (C) 2002, 2005, 2007 The University of Melbourne.
** This file may only be copied under the terms of the GNU Library General
** Public License - see the file COPYING.LIB in the Mercury distribution.
*/

/*
** mercury_construct.h
**
** This module provides utility functions for constructing terms, for use by
** the standard library.
*/

#ifndef MERCURY_CONSTRUCT_H
#define MERCURY_CONSTRUCT_H

#include "mercury_types.h"
#include "mercury_type_info.h"
#include "mercury_stack_layout.h"

union MR_Construct_Functor_Union {
	const MR_EnumFunctorDesc		*enum_functor_desc;
	const MR_ForeignEnumFunctorDesc		*foreign_enum_functor_desc;
	const MR_NotagFunctorDesc		*notag_functor_desc;
	const MR_DuFunctorDesc			*du_functor_desc;
};

typedef struct MR_Construct_Info_Struct {
	MR_ConstString				functor_name;
	MR_Integer				arity;
	const MR_PseudoTypeInfo			*arg_pseudo_type_infos;
	const MR_ConstString			*arg_names;
	MR_TypeCtorRep				type_ctor_rep;
	union MR_Construct_Functor_Union	functor_info;
} MR_Construct_Info;

/*
** MR_get_num_functors:
**
** Get the number of functors for a type. If it isn't a
** discriminated union, return -1.
**
** You need to save and restore transient registers around
** calls to this function.
*/

extern	int	MR_get_num_functors(MR_TypeInfo type_info);

/*
** MR_get_functors_check_range:
**
** Check that functor_number is in range, and get the functor
** info if it is. Return MR_FALSE if it is out of range, or
** if MR_get_functor_info returns MR_FALSE, otherwise return MR_TRUE.
**
** You need to save and restore transient registers around
** calls to this function.
*/

extern	MR_bool	MR_get_functors_check_range(int functor_number,
			MR_TypeInfo type_info,
			MR_Construct_Info *construct_info);

/*
** MR_typecheck_arguments:
**
** Given a list of univs (`arg_list'), and a vector of
** type_infos (`arg_vector'), checks that they are all of the
** same type; if so, returns MR_TRUE, otherwise returns MR_FALSE;
** `arg_vector' may contain type variables, these
** will be filled in by the type arguments of `type_info'.
**
** Assumes the length of the list has already been checked.
**
** You need to save and restore transient registers around
** calls to this function.
*/

extern	MR_bool	MR_typecheck_arguments(MR_TypeInfo type_info,
			int arity, MR_Word arg_list,
			const MR_PseudoTypeInfo *arg_pseudo_type_infos);

#endif	/* MERCURY_CONSTRUCT_H */