factor/extra/sequences/extras/extras.factor

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USING: arrays kernel locals math sequences ;
IN: sequences.extras
: reduce1 ( seq quot -- result ) [ unclip ] dip reduce ; inline
:: reduce-r
( list identity quot: ( obj1 obj2 -- obj ) -- result )
list empty?
[ identity ]
[ list rest identity quot reduce-r list first quot call ] if ;
inline recursive
! Quot must have static stack effect, unlike "reduce"
:: reduce* ( seq id quot -- result ) seq
[ id ]
[ unclip id swap quot call( prev elt -- next ) quot reduce* ] if-empty ; inline recursive
:: combos ( list1 list2 -- result ) list2 [ [ 2array ] curry list1 swap map ] map concat ;
: find-all ( seq quot -- elts ) [ [ length iota ] keep ] dip
2009-08-04 18:16:34 -04:00
[ dupd call( a -- ? ) [ 2array ] [ 2drop f ] if ] curry 2map [ ] filter ; inline