factor/core/math/parser/parser.factor

105 lines
2.5 KiB
Factor

! Copyright (C) 2004, 2007 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel math.private namespaces sequences strings arrays
combinators splitting math ;
IN: math.parser
DEFER: base>
: string>ratio ( str radix -- a/b )
>r "/" split1 r> tuck base> >r base> r>
2dup and [ / ] [ 2drop f ] if ;
: digit> ( ch -- n )
{
{ [ dup digit? ] [ CHAR: 0 - ] }
{ [ dup letter? ] [ CHAR: a - 10 + ] }
{ [ dup LETTER? ] [ CHAR: A - 10 + ] }
{ [ t ] [ drop f ] }
} cond ;
: digits>integer ( radix seq -- n )
0 rot [ swapd * + ] curry reduce ;
: valid-digits? ( radix seq -- ? )
{
{ [ dup empty? ] [ 2drop f ] }
{ [ f over memq? ] [ 2drop f ] }
{ [ t ] [ swap [ < ] curry all? ] }
} cond ;
: string>digits ( str -- digits )
[ digit> ] { } map-as ;
: string>integer ( str radix -- n/f )
swap "-" ?head >r
string>digits 2dup valid-digits?
[ digits>integer r> [ neg ] when ] [ r> 3drop f ] if ;
: base> ( str radix -- n/f )
{
{ [ CHAR: / pick member? ] [ string>ratio ] }
{ [ CHAR: . pick member? ] [ drop string>float ] }
{ [ t ] [ string>integer ] }
} cond ;
: 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 ;
: integer, ( num radix -- )
dup 1 <= [ "Invalid radix" throw ] when
dup >r /mod >digit , dup 0 >
[ r> integer, ] [ r> 2drop ] if ;
GENERIC# >base 1 ( n radix -- str )
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 ( str -- newstr )
{
{
[ CHAR: e over member? ]
[ "e" split1 >r fix-float "e" r> 3append ]
} {
[ CHAR: . over member? ]
[ ]
} {
[ t ]
[ ".0" append ]
}
} cond ;
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 ( n -- str ) 10 >base ;
: >bin ( n -- str ) 2 >base ;
: >oct ( n -- str ) 8 >base ;
: >hex ( n -- str ) 16 >base ;
: # ( n -- ) number>string % ;