I mostly agree, but

> Exists refers to keys in a hash and has nothing to do with variables.

this statement is problematic because Perl's namespaces - including scratchpads° - are actually implemented as hashes.

for instance it's perfectly possible to check the STASH for a package variable

  DB<3> p exists $main::{xxx}

  DB<4> $xxx = 1

  DB<5> p exists $main::{xxx}
1

[download]

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

°) though you'd need PadWalker to access it.

In reply to Re^2: detecting an undefined variable by LanX
in thread detecting an undefined variable by LloydRice

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