32 lines
1.3 KiB
Raku
32 lines
1.3 KiB
Raku
role FIFO {
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method enqueue ( *@values ) { # Add values to queue, returns the number of values added.
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self.push: @values;
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return @values.elems;
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}
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method dequeue ( ) { # Remove and return the first value from the queue.
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# Return Nil if queue is empty.
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return self.elems ?? self.shift !! Nil;
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}
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method is-empty ( ) { # Check to see if queue is empty. Returns Boolean value.
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return self.elems == 0;
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}
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}
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# Example usage:
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my @queue does FIFO;
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say @queue.is-empty; # -> Bool::True
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for <A B C> -> $i { say @queue.enqueue: $i } # 1 \n 1 \n 1
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say @queue.enqueue: Any; # -> 1
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say @queue.enqueue: 7, 8; # -> 2
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say @queue.is-empty; # -> Bool::False
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say @queue.dequeue; # -> A
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say @queue.elems; # -> 4
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say @queue.dequeue; # -> B
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say @queue.is-empty; # -> Bool::False
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say @queue.enqueue('OHAI!'); # -> 1
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say @queue.dequeue until @queue.is-empty; # -> C \n Any() \n [7 8] \n OHAI!
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say @queue.is-empty; # -> Bool::True
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say @queue.dequeue; # ->
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