The Perl version is also very fast - not as fast as C, but much easier to write!

No, it's practically exactly the same, op for op.

So to implement a FIFO queue in Perl, just push new entries onto the bottom of the Perl array and shift out "oldest" entries from the top.

A circular buffer is a queue (FIFO), but a queue is not necessarily a circular buffer. You didn't provide any indication as to whether the code you posted is a suitable solution for the OP or not.

It turns out the code you (and I) posted does exhibit the same characteristics as a circular buffer. See my reply.

The Perl array also can implement essentially the equivalent of a 'C' doubly linked list. [...] But in Perl you can use splice()

If you can use splice, you don't have a linked list. Linked lists take O(1) to remove a previously found element. splice takes O(N).

In reply to Re^2: Circular buffer by ikegami
in thread Circular buffer by Anonymous Monk

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