Two thoughts...

1. IMHO using $_ to hold a pattern is anyway a bad style!

a) since the default DWIM behaviour for m/PATTERN/ is to match in $_

b) because the content of $_ could easily be affected by other side effects.

2. So what is the behavior you expect from an empty match-pattern?

Some will expect always true¹ others always false² and a third party would want a warning³.

So you should take care about valid patterns.

Cheers Rolf

1) mathematically correct

2) "empty strings are false" and "nothing to match => no match"!

3) 'Invalid pattern "" in line ...'

In reply to Re: grep trouble by LanX
in thread grep trouble by LogMiner

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