I found something.

https://groups.google.com/forum/#!searchin/comp.lang.perl.misc/randomizing$20/comp.lang.perl.misc/D8Znz7CbCyg/ZXcyK3OTUEIJ

PerlGuru + something about randomizing array + foreach+splice+last

'If any part of LIST is an array, "foreach" will get very confused > if you add or remove elements within the loop body, for example with > "splice". So don't do that.' > > Your testing seems to prove that this is a special case, certainly a > very useful one. > Please explain what makes it special. The 'last' makes it special. By exiting the loop there is no opportunity for confusion.
But I did not find see "Anyway, don't do it, even with "last"" advices :(

In reply to Re^4: foreach argument modification inside loop, followed by return from loop by vsespb
in thread foreach argument modification inside loop, followed by return from loop by vsespb

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