factor/library/math/math-combinators.factor

! :folding=indent:collapseFolds=1:

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! Copyright (C) 2003, 2004 Slava Pestov.
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IN: math
USE: combinators
USE: kernel
USE: stack

: times ( n quot -- )
    #! Evaluate a quotation n times.
    #!
    #! In order to compile, the code must produce as many values
    #! as it consumes.
    tuck >r dup 0 <= [
        r> 3drop
    ] [
        pred >r call r> r> times
    ] ifte ; inline interpret-only

: (times) ( limit n quot -- )
    pick pick <= [
        3drop
    ] [
        tuck >r tuck >r rot >r call r> r> succ r> (times)
    ] ifte ; inline interpret-only

: times* ( n quot -- )
    #! 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 swap (times) ; inline interpret-only