factor/library/math/math-combinators.factor

57 lines
2.0 KiB
Factor

! :folding=indent:collapseFolds=1:
! $Id$
!
! Copyright (C) 2003, 2004 Slava Pestov.
!
! Redistribution and use in source and binary forms, with or without
! modification, are permitted provided that the following conditions are met:
!
! 1. Redistributions of source code must retain the above copyright notice,
! this list of conditions and the following disclaimer.
!
! 2. Redistributions in binary form must reproduce the above copyright notice,
! this list of conditions and the following disclaimer in the documentation
! and/or other materials provided with the distribution.
!
! THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
! INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
! FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
! DEVELOPERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
! SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
! PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
! OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
! WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
! OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
! ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
IN: math
USE: combinators
USE: kernel
USE: stack
: times ( n [ code ] -- )
#! Evaluate a quotation n times.
#!
#! In order to compile, the code must produce as many values
#! as it consumes.
[
over 0 >
] [
tuck >r pred >r call r> r>
] while 2drop ; inline interpret-only
: times* ( n [ code ] -- )
#! Evaluate a quotation n times, pushing the index at each
#! iteration. The index ranges from 0 to n-1.
#!
#! In order to compile, the code must consume one more value
#! than it produces.
0 rot
[
2dup <
] [
>r 2dup succ >r >r swap call r> r> r>
] while
3drop ; inline interpret-only