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Scala uses [$]_ in very similar ways and everyone loves it.

"_" in Scala is not a magic variable like in Perl. It's a very mechanical syntax transformation, it just expands to "x => x" (or equivalent, and without colliding with any "x" that's already defined).

In practice maybe the use is similar. But having a comprehensible theoretical model makes all the difference in terms of making sure you can actually read the code and understand what will happen.

There is nothing particularly magical about $_. It is merely a global variable that is optionally used implicitly in various builtins, as well as scope-localized by loop control constructs.

Are you sure you're not just used to it? The description you've just given sounds very magic to me.

That depends on how you define "magic". I typically do so as "cannot be implemented in the language itself", which does not apply to $_, as it can be reimplemented in Perl itself. If i was bored enough i could create a module that sets up a $this variable that acts exactly the same, in pure perl.

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