42 lines
1 KiB
Forth
42 lines
1 KiB
Forth
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\ *****************************************************************************
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\ * Copyright (c) 2004, 2008 IBM Corporation
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\ * All rights reserved.
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\ * This program and the accompanying materials
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\ * are made available under the terms of the BSD License
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\ * which accompanies this distribution, and is available at
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\ * http://www.opensource.org/licenses/bsd-license.php
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\ *
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\ * Contributors:
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\ * IBM Corporation - initial implementation
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\ ****************************************************************************/
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: ([IF])
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BEGIN
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BEGIN parse-word dup 0= WHILE
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2drop refill
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REPEAT
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2dup s" [IF]" str= IF 1 throw THEN
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2dup s" [ELSE]" str= IF 2 throw THEN
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2dup s" [THEN]" str= IF 3 throw THEN
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s" \" str= IF linefeed parse 2drop THEN
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AGAIN
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;
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: [IF] ( flag -- )
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IF exit THEN
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1 BEGIN
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['] ([IF]) catch
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CASE
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1 OF 1+ ENDOF
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2 OF dup 1 = if 1- then ENDOF
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3 OF 1- ENDOF
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ENDCASE
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dup 0 <=
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UNTIL drop
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; immediate
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: [ELSE] 0 [COMPILE] [IF] ; immediate
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: [THEN] ; immediate
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