11 lines
180 B
PostScript
11 lines
180 B
PostScript
% empty? is already defined.
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/push {exch cons}.
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/pop {uncons exch pop}.
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[2 3 4 5 6] 1 push
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= [1 2 3 4 5 6]
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[1 2 3 4 5 6] pop
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=[2 3 4 5 6]
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[2 3 4 5 6] empty?
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=false
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[] empty?
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=true
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