! :folding=indent:collapseFolds=1:

! $Id$
!
! Copyright (C) 2003, 2004 Slava Pestov.
! 
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! modification, are permitted provided that the following conditions are met:
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IN: lists
USE: combinators
USE: kernel
USE: namespaces
USE: stack

: append@ ( [ list ] var -- )
    #! Append a proper list stored in a variable with another
    #! list, storing the result back in the variable.
    #! given variable using 'append'.
    tuck get swap append put ;

: add@ ( elem var -- )
    #! Add an element at the end of a proper list stored in a
    #! variable, storing the result back in the variable.
    tuck get swap add put ;

: cons@ ( x var -- )
    #! Prepend x to the list stored in var.
    tuck get cons put ;

: remove@ ( obj var -- )
    #! Remove all occurrences of the object from the list
    #! stored in the variable.
    tuck get remove put ;

: unique@ ( elem var -- )
    #! Prepend an element to the proper list stored in a
    #! variable if it is not already contained in the list.
    tuck get unique put ;

: [, ( -- )
    #! Begin constructing a list.
    <namespace> >n f "list-buffer" set ;

: , ( obj -- )
    #! Append an object to the currently constructing list.
    "list-buffer" cons@ ;

: list, ( list -- )
    #! Append each element to the currently constructing list.
    [ , ] each ;

: ,] ( -- list )
    #! Finish constructing a list and push it on the stack.
    "list-buffer" get nreverse n> drop ;