factor/basis/compiler/utilities/utilities.factor

33 lines
857 B
Factor

! Copyright (C) 2008, 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel sequences sequences.private arrays vectors fry
math math.order namespaces assocs ;
IN: compiler.utilities
: flattener ( seq quot -- seq vector quot' )
over length <vector> [
dup
'[
@ [
dup array?
[ _ push-all ] [ _ push ] if
] when*
]
] keep ; inline
: flattening ( seq quot combinator -- seq' )
[ flattener ] dip dip { } like ; inline
: map-flat ( seq quot -- seq' ) [ each ] flattening ; inline
: 2map-flat ( seq quot -- seq' ) [ 2each ] flattening ; inline
SYMBOL: yield-hook
yield-hook [ [ ] ] initialize
: alist-max ( alist -- pair )
[ ] [ [ [ second ] bi@ > ] most ] map-reduce ;
: penultimate ( seq -- elt ) [ length 2 - ] keep nth ;