It's one of the cases where quoting your variables can have an unexpected effect: 
$x = "abc";
say 1 while  $x  =~ /c/g;
say 2 while "$x" =~ /c/g;

[download]
will print a single 1, and an unlimited number of 2s.

In reply to Re: Program enters infinite loop, can you see why? by JavaFan
in thread Program enters infinite loop, can you see why? by BrowserUk

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