[bpt/guile.git] / libguile / procs.h

/* classes: h_files */

#ifndef SCM_PROCS_H
#define SCM_PROCS_H

/* Copyright (C) 1995,1996,1998,1999,2000,2001, 2006, 2008, 2009 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 3 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

\f

#include "libguile/__scm.h"

\f


/* Subrs 
 */

#define SCM_SUBR_META_INFO(x)  ((SCM *) SCM_CELL_WORD_3 (x))
#define SCM_SUBR_NAME(x) (SCM_SUBR_META_INFO (x) [0])
#define SCM_SUBRF(x) ((SCM (*)()) SCM_CELL_WORD_1 (x))
#define SCM_DSUBRF(x) ((double (*)()) SCM_CELL_WORD_1 (x))
#define SCM_SUBR_PROPS(x) (SCM_SUBR_META_INFO (x) [1])
#define SCM_SUBR_GENERIC(x) ((SCM *) SCM_CELL_WORD_2 (x))
#define SCM_SET_SUBR_GENERIC(x, g) (*((SCM *) SCM_CELL_WORD_2 (x)) = (g))
#define SCM_SET_SUBR_GENERIC_LOC(x, g) (SCM_SET_CELL_WORD_2 (x, (scm_t_bits) g))

/* Return the most suitable subr type for a subr with REQ required arguments,
   OPT optional arguments, and REST (0 or 1) arguments.  This has to be in
   sync with `create_gsubr ()'.  */
#define SCM_SUBR_ARITY_TO_TYPE(req, opt, rest)				\
  ((rest) == 0								\
   ? ((opt) == 0							\
      ? ((req) == 0							\
	 ? scm_tc7_subr_0						\
	 : ((req) == 1							\
	    ? scm_tc7_subr_1						\
	    : ((req) == 2						\
	       ? scm_tc7_subr_2						\
	       : ((req) == 3						\
		  ? scm_tc7_subr_3					\
		  : scm_tc7_gsubr					\
		    | (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))))	\
      : ((opt) == 1							\
	 ? ((req) == 0							\
	    ? scm_tc7_subr_1o						\
	    : ((req) == 1						\
	       ? scm_tc7_subr_2o					\
	       : scm_tc7_gsubr |					\
	         (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))		\
	 : scm_tc7_gsubr |						\
	   (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))			\
   : ((rest) == 1							\
      ? ((opt) == 0							\
	 ? ((req) == 0							\
	    ? scm_tc7_lsubr						\
	    : ((req) == 2						\
	       ? scm_tc7_lsubr_2					\
	       : scm_tc7_gsubr						\
	         | (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))		\
	 : scm_tc7_gsubr						\
	   | (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U))		\
      : scm_tc7_gsubr							\
        | (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))


\f
/* Closures
 */

#define SCM_CLOSUREP(x) (!SCM_IMP(x) && (SCM_TYP3 (x) == scm_tc3_closure))
#define SCM_CLOSCAR(x) SCM_PACK (SCM_CELL_WORD_0 (x) - scm_tc3_closure)
#define SCM_CODE(x) SCM_CAR (SCM_CLOSCAR (x))
#define SCM_CLOSURE_FORMALS(x) SCM_CAR (SCM_CODE (x))
#define SCM_CLOSURE_BODY(x) SCM_CDR (SCM_CODE (x))
#define SCM_PROCPROPS(x) SCM_CDR (SCM_CLOSCAR (x))
#define SCM_SETPROCPROPS(x, p) SCM_SETCDR (SCM_CLOSCAR (x), p)
#define SCM_ENV(x) SCM_CELL_OBJECT_1 (x)
#define SCM_TOP_LEVEL(ENV)  (scm_is_null (ENV) || (scm_is_true (scm_procedure_p (SCM_CAR (ENV)))))

/* Procedure-with-setter

   Four representations for procedure-with-setters were
   considered before selecting this one:

   1. A closure where the CODE and ENV slots are used to represent
   the getter and a new SETTER slot is used for the setter.  The
   original getter is stored as a `getter' procedure property.  For
   closure getters, the CODE and ENV slots contains a copy of the
   getter's CODE and ENV slots.  For subr getters, the CODE contains
   a call to the subr.

   2. A compiled closure with a call to the getter in the cclo
   procedure.  The getter and setter are stored in slots 1 and 2.

   3. An entity (i.e. a struct with an associated procedure) with a
   call to the getter in the entity procedure and the setter stored
   in slot 0.  The original getter is stored in slot 1.

   4. A new primitive procedure type supported in the evaluator.  The
   getter and setter are stored in a GETTER and SETTER slot.  A call
   to this procedure type results in a retrieval of the getter and a
   jump back to the correct eval dispatcher.

   Representation 4 was selected because of efficiency and
   simplicity.

   Rep 1 has the advantage that there is zero penalty for closure
   getters, but primitive getters will get considerable overhead
   because the procedure-with-getter will be a closure which calls
   the getter.

   Rep 3 has the advantage that a GOOPS accessor can be a subclass of
   <procedure-with-setter>, but together with rep 2 it suffers from a
   three level dispatch for non-GOOPS getters:

     cclo/struct --> dispatch proc --> getter

   This is because the dispatch procedure must take an extra initial
   argument (cclo for rep 2, struct for rep 3).

   Rep 4 has the single disadvantage that it uses up one tc7 type
   code, but the plan for uniform vectors will very likely free tc7
   codes, so this is probably no big problem.  Also note that the
   GETTER and SETTER slots can live directly on the heap, using the
   new four-word cells.  */

#define SCM_PROCEDURE_WITH_SETTER_P(obj) (!SCM_IMP(obj) && (SCM_TYP7 (obj) == scm_tc7_pws))
#define SCM_PROCEDURE(obj) SCM_CELL_OBJECT_1 (obj)
#define SCM_SETTER(obj) SCM_CELL_OBJECT_2 (obj)


\f

SCM_API SCM scm_c_make_subr (const char *name, long type, SCM (*fcn)());
SCM_API SCM scm_c_make_subr_with_generic (const char *name, long type,
					  SCM (*fcn)(), SCM *gf);
SCM_API SCM scm_c_define_subr (const char *name, long type, SCM (*fcn)());
SCM_API SCM scm_c_define_subr_with_generic (const char *name, long type,
					    SCM (*fcn)(), SCM *gf);
SCM_API SCM scm_procedure_p (SCM obj);
SCM_API SCM scm_closure_p (SCM obj);
SCM_API SCM scm_thunk_p (SCM obj);
SCM_API int scm_subr_p (SCM obj);
SCM_API SCM scm_procedure_documentation (SCM proc);
SCM_API SCM scm_procedure_with_setter_p (SCM obj);
SCM_API SCM scm_make_procedure_with_setter (SCM procedure, SCM setter);
SCM_API SCM scm_procedure (SCM proc);
SCM_API SCM scm_setter (SCM proc);
SCM_INTERNAL void scm_init_procs (void);

#endif  /* SCM_PROCS_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/
Commit	Line	Data
0f2d19dd JB	1	/* classes: h_files */
0f2d19dd JB	2
22a52da1 DH	3	#ifndef SCM_PROCS_H
22a52da1 DH	4	#define SCM_PROCS_H
dee01b01	5
f48393a9	6	/* Copyright (C) 1995,1996,1998,1999,2000,2001, 2006, 2008, 2009 Free Software Foundation, Inc.
dee01b01	7	*
73be1d9e	8	* This library is free software; you can redistribute it and/or
53befeb7 NJ	9	* modify it under the terms of the GNU Lesser General Public License
	10	* as published by the Free Software Foundation; either version 3 of
	11	* the License, or (at your option) any later version.
dee01b01	12	*
53befeb7 NJ	13	* This library is distributed in the hope that it will be useful, but
53befeb7 NJ	14	* WITHOUT ANY WARRANTY; without even the implied warranty of
73be1d9e MV	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
73be1d9e MV	16	* Lesser General Public License for more details.
dee01b01	17	*
73be1d9e MV	18	* You should have received a copy of the GNU Lesser General Public
73be1d9e MV	19	* License along with this library; if not, write to the Free Software
53befeb7 NJ	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
53befeb7 NJ	21	* 02110-1301 USA
73be1d9e	22	*/
d3a6bc94	23
0f2d19dd JB	24	\f
0f2d19dd JB	25
b4309c3c	26	#include "libguile/__scm.h"
0f2d19dd JB	27
	28	\f
	29
	30
	31	/* Subrs
	32	*/
	33
2ee5aa25	34	#define SCM_SUBR_META_INFO(x) ((SCM *) SCM_CELL_WORD_3 (x))
ce471ab8	35	#define SCM_SUBR_NAME(x) (SCM_SUBR_META_INFO (x) [0])
e59bb516 DH	36	#define SCM_SUBRF(x) ((SCM (*)()) SCM_CELL_WORD_1 (x))
e59bb516 DH	37	#define SCM_DSUBRF(x) ((double (*)()) SCM_CELL_WORD_1 (x))
2ee5aa25 LC	38	#define SCM_SUBR_PROPS(x) (SCM_SUBR_META_INFO (x) [1])
	39	#define SCM_SUBR_GENERIC(x) ((SCM *) SCM_CELL_WORD_2 (x))
	40	#define SCM_SET_SUBR_GENERIC(x, g) (((SCM ) SCM_CELL_WORD_2 (x)) = (g))
	41	#define SCM_SET_SUBR_GENERIC_LOC(x, g) (SCM_SET_CELL_WORD_2 (x, (scm_t_bits) g))
74cc8503	42
f0eb5ae6 LC	43	/* Return the most suitable subr type for a subr with REQ required arguments,
	44	OPT optional arguments, and REST (0 or 1) arguments. This has to be in
	45	sync with `create_gsubr ()'. */
	46	#define SCM_SUBR_ARITY_TO_TYPE(req, opt, rest) \
	47	((rest) == 0 \
	48	? ((opt) == 0 \
	49	? ((req) == 0 \
	50	? scm_tc7_subr_0 \
	51	: ((req) == 1 \
	52	? scm_tc7_subr_1 \
	53	: ((req) == 2 \
	54	? scm_tc7_subr_2 \
	55	: ((req) == 3 \
	56	? scm_tc7_subr_3 \
	57	: scm_tc7_gsubr \
	58	\| (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U))))) \
	59	: ((opt) == 1 \
	60	? ((req) == 0 \
	61	? scm_tc7_subr_1o \
	62	: ((req) == 1 \
	63	? scm_tc7_subr_2o \
	64	: scm_tc7_gsubr \| \
	65	(SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U))) \
	66	: scm_tc7_gsubr \| \
	67	(SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U))) \
	68	: ((rest) == 1 \
	69	? ((opt) == 0 \
	70	? ((req) == 0 \
	71	? scm_tc7_lsubr \
	72	: ((req) == 2 \
	73	? scm_tc7_lsubr_2 \
	74	: scm_tc7_gsubr \
	75	\| (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U))) \
	76	: scm_tc7_gsubr \
	77	\| (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)) \
	78	: scm_tc7_gsubr \
	79	\| (SCM_GSUBR_MAKTYPE (req, opt, rest) << 8U)))
46f9baf4 LC	80
	81
	82	\f
0f2d19dd JB	83	/* Closures
	84	*/
	85
dee01b01	86	#define SCM_CLOSUREP(x) (!SCM_IMP(x) && (SCM_TYP3 (x) == scm_tc3_closure))
f9a64404	87	#define SCM_CLOSCAR(x) SCM_PACK (SCM_CELL_WORD_0 (x) - scm_tc3_closure)
a54367e2	88	#define SCM_CODE(x) SCM_CAR (SCM_CLOSCAR (x))
726d810a	89	#define SCM_CLOSURE_FORMALS(x) SCM_CAR (SCM_CODE (x))
f9450cdb	90	#define SCM_CLOSURE_BODY(x) SCM_CDR (SCM_CODE (x))
a54367e2 MD	91	#define SCM_PROCPROPS(x) SCM_CDR (SCM_CLOSCAR (x))
a54367e2 MD	92	#define SCM_SETPROCPROPS(x, p) SCM_SETCDR (SCM_CLOSCAR (x), p)
22a52da1	93	#define SCM_ENV(x) SCM_CELL_OBJECT_1 (x)
d2e53ed6	94	#define SCM_TOP_LEVEL(ENV) (scm_is_null (ENV) \|\| (scm_is_true (scm_procedure_p (SCM_CAR (ENV)))))
0f2d19dd	95
03f27074 JB	96	/* Procedure-with-setter
	97
	98	Four representations for procedure-with-setters were
	99	considered before selecting this one:
	100
	101	1. A closure where the CODE and ENV slots are used to represent
	102	the getter and a new SETTER slot is used for the setter. The
	103	original getter is stored as a `getter' procedure property. For
	104	closure getters, the CODE and ENV slots contains a copy of the
	105	getter's CODE and ENV slots. For subr getters, the CODE contains
	106	a call to the subr.
	107
	108	2. A compiled closure with a call to the getter in the cclo
	109	procedure. The getter and setter are stored in slots 1 and 2.
	110
	111	3. An entity (i.e. a struct with an associated procedure) with a
	112	call to the getter in the entity procedure and the setter stored
	113	in slot 0. The original getter is stored in slot 1.
	114
	115	4. A new primitive procedure type supported in the evaluator. The
	116	getter and setter are stored in a GETTER and SETTER slot. A call
	117	to this procedure type results in a retrieval of the getter and a
	118	jump back to the correct eval dispatcher.
	119
	120	Representation 4 was selected because of efficiency and
	121	simplicity.
	122
	123	Rep 1 has the advantage that there is zero penalty for closure
	124	getters, but primitive getters will get considerable overhead
	125	because the procedure-with-getter will be a closure which calls
	126	the getter.
	127
	128	Rep 3 has the advantage that a GOOPS accessor can be a subclass of
	129	<procedure-with-setter>, but together with rep 2 it suffers from a
	130	three level dispatch for non-GOOPS getters:
	131
	132	cclo/struct --> dispatch proc --> getter
	133
	134	This is because the dispatch procedure must take an extra initial
	135	argument (cclo for rep 2, struct for rep 3).
	136
	137	Rep 4 has the single disadvantage that it uses up one tc7 type
	138	code, but the plan for uniform vectors will very likely free tc7
	139	codes, so this is probably no big problem. Also note that the
	140	GETTER and SETTER slots can live directly on the heap, using the
	141	new four-word cells. */
	142
dee01b01	143	#define SCM_PROCEDURE_WITH_SETTER_P(obj) (!SCM_IMP(obj) && (SCM_TYP7 (obj) == scm_tc7_pws))
0cbaaf0b DH	144	#define SCM_PROCEDURE(obj) SCM_CELL_OBJECT_1 (obj)
0cbaaf0b DH	145	#define SCM_SETTER(obj) SCM_CELL_OBJECT_2 (obj)
64c4580b	146
9de33deb	147
0f2d19dd JB	148	\f
0f2d19dd JB	149
33b001fd MV	150	SCM_API SCM scm_c_make_subr (const char name, long type, SCM (fcn)());
	151	SCM_API SCM scm_c_make_subr_with_generic (const char *name, long type,
	152	SCM (fcn)(), SCM gf);
	153	SCM_API SCM scm_c_define_subr (const char name, long type, SCM (fcn)());
	154	SCM_API SCM scm_c_define_subr_with_generic (const char *name, long type,
	155	SCM (fcn)(), SCM gf);
33b001fd MV	156	SCM_API SCM scm_procedure_p (SCM obj);
	157	SCM_API SCM scm_closure_p (SCM obj);
	158	SCM_API SCM scm_thunk_p (SCM obj);
	159	SCM_API int scm_subr_p (SCM obj);
	160	SCM_API SCM scm_procedure_documentation (SCM proc);
	161	SCM_API SCM scm_procedure_with_setter_p (SCM obj);
	162	SCM_API SCM scm_make_procedure_with_setter (SCM procedure, SCM setter);
	163	SCM_API SCM scm_procedure (SCM proc);
	164	SCM_API SCM scm_setter (SCM proc);
102dbb6f	165	SCM_INTERNAL void scm_init_procs (void);
0f2d19dd	166
22a52da1	167	#endif /* SCM_PROCS_H */
89e00824 ML	168
	169	/*
	170	Local Variables:
	171	c-file-style: "gnu"
	172	End:
	173	*/