35 lines
533 B
Text
35 lines
533 B
Text
define :queue [][
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init: [
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this\items: []
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]
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]
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empty?: function [this :queue][
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zero? this\items
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]
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push: function [this :queue, item][
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this\items: this\items ++ item
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]
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pop: function [this :queue][
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ensure -> not? empty? this
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result: this\items\0
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this\items: remove.index this\items 0
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return result
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]
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Q: to :queue []
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push Q 1
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push Q 2
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push Q 3
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print ["queue is empty?" empty? Q]
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print ["popping:" pop Q]
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print ["popping:" pop Q]
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print ["popping:" pop Q]
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print ["queue is empty?" empty? Q]
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