$! is tied to a variable that is a bit. Therefore it can only be 0 and 1. Set it to a true value and it sets itself to 1. Set it to a false one and it becomes 0. So subtracting 1 from it when it is 0 gives -1 (true) and sets it to 1. Subtracting 1 from 1 gives 0 again.

When you know how it works, not that complex. But when you first see it it is a bit surprising... (Cue groans.)

In reply to Re: Re: Re: Re: Array Parse by Anonymous Monk
in thread Array Parse by Anonymous Monk

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