What would it even mean? Should it check if they all exist, or if any exist?

And that's why it doesn't exist. It's not clear what that should do, it's not clear what it does by looking at it, it's not something that's commonly needed, and it's easily done with slightly more code.

If you want to check if all of the elements exist, you can use 

all { exists( $h{ $_ } ) } @keys

[download]

If you want to check if any of the elements exist, you can use 

any { exists( $h{ $_ } ) } @keys

[download]

In reply to Re: Why doesn't exist work with hash slices? by ikegami
in thread Why doesn't exist work with hash slices? by Anonymous Monk

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