factor/core/grouping/grouping.factor

69 lines
1.5 KiB
Factor

! Copyright (C) 2005, 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel math math.order strings arrays vectors sequences
accessors ;
IN: grouping
TUPLE: abstract-groups seq n ;
: check-groups dup 0 <= [ "Invalid group count" throw ] when ; inline
: new-groups ( seq n class -- groups )
>r check-groups r> boa ; inline
GENERIC: group@ ( n groups -- from to seq )
M: abstract-groups nth group@ subseq ;
M: abstract-groups set-nth group@ <slice> 0 swap copy ;
M: abstract-groups like drop { } like ;
INSTANCE: abstract-groups sequence
TUPLE: groups < abstract-groups ;
: <groups> ( seq n -- groups )
groups new-groups ; inline
M: groups length
[ seq>> length ] [ n>> ] bi [ + 1- ] keep /i ;
M: groups set-length
[ n>> * ] [ seq>> ] bi set-length ;
M: groups group@
[ n>> [ * dup ] keep + ] [ seq>> ] bi [ length min ] keep ;
TUPLE: sliced-groups < groups ;
: <sliced-groups> ( seq n -- groups )
sliced-groups new-groups ; inline
M: sliced-groups nth group@ <slice> ;
TUPLE: clumps < abstract-groups ;
: <clumps> ( seq n -- clumps )
clumps new-groups ; inline
M: clumps length
[ seq>> length ] [ n>> ] bi - 1+ ;
M: clumps set-length
[ n>> + 1- ] [ seq>> ] bi set-length ;
M: clumps group@
[ n>> over + ] [ seq>> ] bi ;
TUPLE: sliced-clumps < clumps ;
: <sliced-clumps> ( seq n -- clumps )
sliced-clumps new-groups ; inline
M: sliced-clumps nth group@ <slice> ;
: group ( seq n -- array ) <groups> { } like ;
: clump ( seq n -- array ) <clumps> { } like ;