factor/library/math/parse-numbers.factor

85 lines
2.1 KiB
Factor

! Copyright (C) 2004, 2006 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
IN: math
USING: errors generic kernel math-internals namespaces sequences
strings ;
DEFER: base>
: string>ratio ( str radix -- a/b )
>r "/" split1 r> tuck base> >r base> r>
2dup and [ / ] [ 2drop f ] if ;
GENERIC: digit> ( ch -- n )
M: digit digit> CHAR: 0 - ;
M: letter digit> CHAR: a - 10 + ;
M: LETTER digit> CHAR: A - 10 + ;
M: object digit> drop f ;
: digit+ ( num digit base -- num )
pick pick and
[ 2dup < [ rot * + ] [ 3drop f ] if ] [ 3drop f ] if ;
: (string>integer) ( radix str -- num )
dup empty? [
2drop f
] [
0 [ digit> pick digit+ ] reduce nip
] if ;
: string>integer ( string radix -- n )
swap "-" ?head >r (string>integer) dup r> and [ neg ] when ;
: base> ( string radix -- n )
{
{ [ CHAR: / pick member? ] [ string>ratio ] }
{ [ CHAR: . pick member? ] [ drop string>float ] }
{ [ t ] [ string>integer ] }
} cond ;
: string>number ( string -- num ) 10 base> ;
: bin> ( string -- num ) 2 base> ;
: oct> ( string -- num ) 8 base> ;
: hex> ( string -- num ) 16 base> ;
: >digit ( n -- ch )
dup 10 < [ CHAR: 0 + ] [ 10 - CHAR: a + ] if ;
: integer, ( num radix -- )
dup >r /mod >digit , dup 0 >
[ r> integer, ] [ r> 2drop ] if ;
G: >base ( num radix -- string ) 1 standard-combination ;
M: integer >base
[
over 0 < [
swap neg swap integer, CHAR: - ,
] [
integer,
] if
] "" make reverse ;
M: ratio >base
[
over numerator over >base %
CHAR: / ,
swap denominator swap >base %
] "" make ;
: fix-float
CHAR: . over member? [ ".0" append ] unless ;
M: float >base
drop {
{ [ dup 1.0/0.0 = ] [ drop "1.0/0.0" ] }
{ [ dup -1.0/0.0 = ] [ drop "-1.0/0.0" ] }
{ [ dup fp-nan? ] [ drop "0.0/0.0" ] }
{ [ t ] [ float>string fix-float ] }
} cond ;
: number>string ( num -- string ) 10 >base ;
: >bin ( num -- string ) 2 >base ;
: >oct ( num -- string ) 8 >base ;
: >hex ( num -- string ) 16 >base ;