That is a check for file existence, not a check as to whether you've been passed something intended to be treated as a filename. A filename may be the name of a file that does not (yet) exist.

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re^8: Best way to check if something is a file handle? by tobyink
in thread Best way to check if something is a file handle? by tobyink

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