factor/core/math/parser/parser.factor

163 lines
3.6 KiB
Factor

! Copyright (C) 2004, 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel math.private namespaces sequences strings
arrays combinators splitting math assocs make ;
IN: math.parser
: digit> ( ch -- n )
H{
{ CHAR: 0 0 }
{ CHAR: 1 1 }
{ CHAR: 2 2 }
{ CHAR: 3 3 }
{ CHAR: 4 4 }
{ CHAR: 5 5 }
{ CHAR: 6 6 }
{ CHAR: 7 7 }
{ CHAR: 8 8 }
{ CHAR: 9 9 }
{ CHAR: A 10 }
{ CHAR: B 11 }
{ CHAR: C 12 }
{ CHAR: D 13 }
{ CHAR: E 14 }
{ CHAR: F 15 }
{ CHAR: a 10 }
{ CHAR: b 11 }
{ CHAR: c 12 }
{ CHAR: d 13 }
{ CHAR: e 14 }
{ CHAR: f 15 }
} at ;
: string>digits ( str -- digits )
[ digit> ] { } map-as ;
: digits>integer ( seq radix -- n )
0 swap [ swapd * + ] curry reduce ;
DEFER: base>
<PRIVATE
SYMBOL: radix
SYMBOL: negative?
: sign ( -- str ) negative? get "-" "+" ? ;
: with-radix ( radix quot -- )
radix swap with-variable ; inline
: (base>) ( str -- n ) radix get base> ;
: whole-part ( str -- m n )
sign split1 [ (base>) ] dip
dup [ (base>) ] [ drop 0 swap ] if ;
: string>ratio ( str -- a/b )
"-" ?head dup negative? set swap
"/" split1 (base>) [ whole-part ] dip
3dup and and [ / + swap [ neg ] when ] [ 2drop 2drop f ] if ;
: valid-digits? ( seq -- ? )
{
{ [ dup empty? ] [ drop f ] }
{ [ f over memq? ] [ drop f ] }
[ radix get [ < ] curry all? ]
} cond ;
: string>integer ( str -- n/f )
"-" ?head swap
string>digits dup valid-digits?
[ radix get digits>integer swap [ neg ] when ] [ 2drop f ] if ;
PRIVATE>
: base> ( str radix -- n/f )
[
CHAR: / over member? [
string>ratio
] [
CHAR: . over member? [
string>float
] [
string>integer
] if
] if
] with-radix ;
: string>number ( str -- n/f ) 10 base> ;
: bin> ( str -- n/f ) 2 base> ;
: oct> ( str -- n/f ) 8 base> ;
: hex> ( str -- n/f ) 16 base> ;
: >digit ( n -- ch )
dup 10 < [ CHAR: 0 + ] [ 10 - CHAR: a + ] if ;
: positive>base ( num radix -- str )
dup 1 <= [ "Invalid radix" throw ] when
[ dup 0 > ] swap [ /mod >digit ] curry [ ] "" produce-as nip
dup reverse-here ; inline
PRIVATE>
GENERIC# >base 1 ( n radix -- str )
<PRIVATE
: (>base) ( n -- str ) radix get positive>base ;
PRIVATE>
M: integer >base
over 0 = [
2drop "0"
] [
over 0 > [
positive>base
] [
[ neg ] dip positive>base CHAR: - prefix
] if
] if ;
M: ratio >base
[
dup 0 < negative? set
abs 1 /mod
[ dup zero? [ drop "" ] [ (>base) sign append ] if ]
[
[ numerator (>base) ]
[ denominator (>base) ] bi
"/" glue
] bi* append
negative? get [ CHAR: - prefix ] when
] with-radix ;
: fix-float ( str -- newstr )
{
{
[ CHAR: e over member? ]
[ "e" split1 [ fix-float "e" ] dip 3append ]
} {
[ CHAR: . over member? ]
[ ]
}
[ ".0" append ]
} cond ;
M: float >base
drop {
{ [ dup fp-nan? ] [ drop "0.0/0.0" ] }
{ [ dup 1.0/0.0 = ] [ drop "1.0/0.0" ] }
{ [ dup -1.0/0.0 = ] [ drop "-1.0/0.0" ] }
{ [ dup double>bits HEX: 8000000000000000 = ] [ drop "-0.0" ] }
[ float>string fix-float ]
} cond ;
: number>string ( n -- str ) 10 >base ;
: >bin ( n -- str ) 2 >base ;
: >oct ( n -- str ) 8 >base ;
: >hex ( n -- str ) 16 >base ;
: # ( n -- ) number>string % ;