factor/library/vocabularies.factor

! :folding=indent:collapseFolds=1:

! $Id$
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! Copyright (C) 2004 Slava Pestov.
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IN: words
USE: hashtables
USE: kernel
USE: lists
USE: namespaces

: (search) ( name vocab -- word )
    vocab dup [ hash ] [ 2drop f ] ifte ;

: search ( name list -- word )
    #! Search for a word in a list of vocabularies.
    dup [
        2dup car (search) dup [
            nip nip ( found )
        ] [
            drop cdr search ( check next )
        ] ifte
    ] [
        2drop f ( not found )
    ] ifte ;

: <plist> ( name vocab -- plist )
    "vocabulary" swons swap "name" swons 2list ;

: (create) ( name vocab -- word )
    #! Create an undefined word without adding to a vocabulary.
    <plist> 0 f rot <word> ;

: reveal ( word -- )
    #! Add a new word to its vocabulary.
    global [
        "vocabularies" get [
            dup word-vocabulary
            over word-name
            2list set-object-path
        ] bind
    ] bind ;

: create ( name vocab -- word )
    #! Create a new word in a vocabulary. If the vocabulary
    #! already contains the word, the existing instance is
    #! returned.
    2dup (search) [ nip nip ] [ (create) dup reveal ] ifte* ;

: forget ( word -- )
    #! Remove a word definition.
    dup word-vocabulary vocab [ word-name off ] bind ;