-d $FILE stands for "test to see if $FILE is a directory";

_ stands for "the topic (of the current conversation)"*;

so, -d _ means "test to see if the last tested file is a directory";

*:

$_ is the topic of the for, will be used by default by regexen and a lot of functions
@_ is the collection of topics for a function (the arguments!)
_ is the topic for file tests.
[]s, HTH, Massa (κς,πμ,πλ)

In reply to It's a question of Perl Culture by massa
in thread What does _ mean? by bichonfrise74

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