2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2011--2015 Mike Solomon <mike@mikesolomon.org>
7 LilyPond is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 LilyPond is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
20 #include "unpure-pure-container.hh"
22 // Reroutes a call to the contained function after dropping last two
23 // arguments. Used for applying an "unpure" function in a "pure"
25 class Unpure_pure_call : public Smob1<Unpure_pure_call>
28 LY_DECLARE_SMOB_PROC (&Unpure_pure_call::call, 2, 0, 1)
29 SCM call (SCM arg1, SCM arg2, SCM rest)
31 return scm_apply_0 (scm1 (),
32 scm_list_head (scm_cons2 (arg1, arg2, rest),
38 Unpure_pure_container::pure_part () const
40 return SCM_UNBNDP (scm2 ())
41 ? Unpure_pure_call::make_smob (scm1 ())
45 const char Unpure_pure_container::type_p_name_[] = "ly:unpure-pure-container?";
47 LY_DEFINE (ly_make_unpure_pure_container, "ly:make-unpure-pure-container",
48 1, 1, 0, (SCM unpure, SCM pure),
49 "Make an unpure-pure container. @var{unpure} should be an unpure"
50 " expression, and @var{pure} should be a pure expression. If @var{pure}"
51 " is omitted, the value of @var{unpure} will be used twice,"
52 " except that a callback is given two extra arguments"
53 " that are ignored for the sake of pure calculations.")
55 return Unpure_pure_container::make_smob (unpure, pure);
58 LY_DEFINE (ly_unpure_pure_container_unpure_part, "ly:unpure-pure-container-unpure-part",
60 "Return the unpure part of @var{pc}.")
62 LY_ASSERT_SMOB (Unpure_pure_container, pc, 1);
63 return unsmob<Unpure_pure_container> (pc)->unpure_part ();
66 LY_DEFINE (ly_unpure_pure_container_pure_part, "ly:unpure-pure-container-pure-part",
68 "Return the pure part of @var{pc}.")
70 LY_ASSERT_SMOB (Unpure_pure_container, pc, 1);
71 return unsmob<Unpure_pure_container> (pc)->pure_part ();
75 Unpure_pure_container::print_smob (SCM port, scm_print_state *) const
77 scm_puts ("#<unpure-pure-container ", port);
78 scm_display (unpure_part (), port);
79 if (!is_unchanging ())
82 scm_display (pure_part (), port);
84 scm_puts (" >", port);