It's just an expression. The while loop executes while the expression is true. Expressions can be many things, including $variables, "words", /regexps/, etc.

From the perl faq:

Perl doesn't have a boolean type. 0, "0", "", undef and () are false, all else is true.

So, fill it with an expression, and while the expression is "true", the loop runs.

In reply to Re: ..."while" i do perl... by kschwab
in thread ..."while" i do perl... by john1987

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