factor/library/generic/builtin.factor

43 lines
1.1 KiB
Factor

! Copyright (C) 2004, 2005 Slava Pestov.
! See http://factor.sf.net/license.txt for BSD license.
IN: generic
USING: errors hashtables kernel lists math namespaces parser
sequences strings vectors words ;
! Builtin metaclass for builtin types: fixnum, word, cons, etc.
SYMBOL: builtin
! Global vector mapping type numbers to builtin class objects.
SYMBOL: builtins
builtin [
( generic vtable definition class -- )
rot set-vtable drop
] "add-method" set-word-prop
: builtin-predicate ( class predicate -- )
[
\ type , over types first , \ eq? ,
] make-list define-predicate ;
: register-builtin ( class -- )
dup types first builtins get set-nth ;
: define-builtin ( symbol type# predicate slotspec -- )
>r >r >r
dup intern-symbol
dup r> 1vector "types" set-word-prop
dup builtin define-class
dup r> builtin-predicate
dup r> intern-slots 2dup "slots" set-word-prop
define-slots
register-builtin ;
: type>class ( n -- symbol ) builtins get nth ;
PREDICATE: word builtin metaclass builtin = ;
: type-tag ( type -- tag )
#! Given a type number, return the tag number.
dup 6 > [ drop 3 ] when ;