factor/extra/money/money.factor

35 lines
998 B
Factor

! Copyright (C) 2008 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: grouping io kernel lexer math math.functions math.parser
namespaces sequences splitting ;
IN: money
SYMBOL: currency-token
CHAR: $ currency-token set-global
: dollars/cents ( dollars -- dollars cents )
100 * 100 /mod round >integer ;
: format-money ( dollars cents -- string )
[ number>string ] bi@
[ <reversed> 3 group "," join <reversed> ]
[ 2 CHAR: 0 pad-head ] bi* "." glue ;
: money>string ( number -- string )
dollars/cents format-money currency-token get prefix ;
: money. ( number -- ) money>string print ;
ERROR: not-an-integer x ;
: split-decimal ( str -- neg? dollars cents )
"." split1 [ "-" ?head swap ] dip ;
: parse-decimal ( str -- ratio )
split-decimal [ [ "0" ] when-empty ] bi@
[
[ dup string>number [ ] [ not-an-integer ] ?if ] bi@
] keep length 10^ / + swap [ neg ] when ;
SYNTAX: DECIMAL: scan-token parse-decimal suffix! ;