59 lines
1.1 KiB
Factor
Executable File
59 lines
1.1 KiB
Factor
Executable File
USING: kernel layouts math namespaces sequences sequences.private ;
|
|
IN: math.ranges
|
|
|
|
TUPLE: range from length step ;
|
|
|
|
: <range> ( from to step -- range )
|
|
>r over - r>
|
|
[ / 1+ 0 max >integer ] keep
|
|
range construct-boa ;
|
|
|
|
M: range length ( seq -- n )
|
|
range-length ;
|
|
|
|
M: range nth-unsafe ( n range -- obj )
|
|
[ range-step * ] keep range-from + ;
|
|
|
|
INSTANCE: range immutable-sequence
|
|
|
|
: twiddle 2dup > -1 1 ? ; inline
|
|
|
|
: (a, dup roll + -rot ; inline
|
|
|
|
: ,b) dup neg rot + swap ; inline
|
|
|
|
: [a,b] twiddle <range> ;
|
|
|
|
: (a,b] twiddle (a, <range> ;
|
|
|
|
: [a,b) twiddle ,b) <range> ;
|
|
|
|
: (a,b) twiddle (a, ,b) <range> ;
|
|
|
|
: [0,b] 0 swap [a,b] ;
|
|
|
|
: [1,b] 1 swap [a,b] ;
|
|
|
|
: [0,b) 0 swap [a,b) ;
|
|
|
|
: range-increasing? ( range -- ? )
|
|
range-step 0 > ;
|
|
|
|
: range-decreasing? ( range -- ? )
|
|
range-step 0 < ;
|
|
|
|
: first-or-peek ( seq head? -- elt )
|
|
[ first ] [ peek ] if ;
|
|
|
|
: range-min ( range -- min )
|
|
dup range-increasing? first-or-peek ;
|
|
|
|
: range-max ( range -- max )
|
|
dup range-decreasing? first-or-peek ;
|
|
|
|
: clamp-to-range ( n range -- n )
|
|
tuck range-min max swap range-max min ;
|
|
|
|
: sequence-index-range ( seq -- range )
|
|
length [0,b) ;
|