Oh great Monks, I have a simple (I think) question of understanding. I want to read a file until I find a line containing a pattern. I tried this: 
while (<> and !/pattern/) {}

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but it complained about $_ undefined in m// match. So I then made the assignment to $_ explicit like so and it works great: 
while (defined($_ = <>) and !/pattern) {}

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I am surprised by the need of doing this and would like to understand why. Thank you all!

In reply to $_ not set in while <> by pidloop

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