88 lines
5.2 KiB
Rexx
Executable File
88 lines
5.2 KiB
Rexx
Executable File
#!@OOREXX_SHEBANG_PROGRAM@
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/*----------------------------------------------------------------------------*/
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/* */
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/* Copyright (c) 1995, 2004 IBM Corporation. All rights reserved. */
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/* Copyright (c) 2005-2014 Rexx Language Association. All rights reserved. */
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/* */
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/* This program and the accompanying materials are made available under */
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/* the terms of the Common Public License v1.0 which accompanies this */
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/* distribution. A copy is also available at the following address: */
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/* https://www.oorexx.org/license.html */
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/* */
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/* Redistribution and use in source and binary forms, with or */
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/* without modification, are permitted provided that the following */
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/* conditions are met: */
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/* */
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/* Redistributions of source code must retain the above copyright */
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/* notice, this list of conditions and the following disclaimer. */
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/* Redistributions in binary form must reproduce the above copyright */
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/* notice, this list of conditions and the following disclaimer in */
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/* the documentation and/or other materials provided with the distribution. */
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/* */
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/* Neither the name of Rexx Language Association nor the names */
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/* of its contributors may be used to endorse or promote products */
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/* derived from this software without specific prior written permission. */
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/* */
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/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS */
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/* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT */
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/* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS */
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/* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT */
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/* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, */
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/* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED */
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/* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, */
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/* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY */
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/* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING */
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/* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS */
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/* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
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/* */
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/*----------------------------------------------------------------------------*/
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/******************************************************************************/
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/* stack.rex Open Object Rexx Samples */
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/* */
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/* A stack class */
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/* */
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/* -------------------------------------------------------------------------- */
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/* */
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/* Description: */
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/* This program demonstrates how to implement a stack class using ::class */
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/* and ::method directives. Also included is a short example of the use of */
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/* a stack. */
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/******************************************************************************/
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mystack = .stack~new /* Create a new instance of stack */
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mystack~push('John Smith')
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mystack~push('Bill Brown')
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say 'Size of stack:' mystack~items /* Displays size of stack */
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say 'Pop stack: ' mystack~pop /* Displays item popped off stack */
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say 'Pop stack: ' mystack~pop /* Displays next item popped off */
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say 'Pop stack: ' mystack~pop /* Stack now empty - displays */
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/* "The NIL Object" */
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/* Define the stack class (a subclass of Object Class) */
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::class stack
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/* Define the init method on the stack class */
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::method init
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expose contents /* Object var with stack contents */
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self~init:super /* Run init method of superclass */
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contents = .list~new /* Use a list to keep stack items */
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/* Define the push method on the stack class */
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::method push
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expose contents
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use arg item
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contents~insert(item, .nil)
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/* Define the pop method on the stack class */
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::method pop
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expose contents
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if contents~items > 0 then
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return contents~remove(contents~first)
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else
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return .nil
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/* Define the items method on the stack class to return number of items */
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::method items
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expose contents
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return contents~items
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