It occurred to me that in my real code I don't actually need the value of @foo afterwards, so I should just use shift: 
while (@foo) {
   my $x = shift @foo;
   push @foo, 'h' if whatever();
}

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In reply to Re^2: changing array size in foreach loop: is it safe? by Errto
in thread changing array size in foreach loop: is it safe? by Errto

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