It has something to do with BEGIN

I have found this information:

BEGIN: A BEGIN code block is executed as soon as possible, that is, the moment it is completely defined, even before the rest of the containing file (or string) is parsed

So I suspect that that means that in case the BEGIN is not there the parser will detect the variable $x before it is created. In case the BEGIN is there, it is guarantied to execute that block first, so before it sees $x (or in this case actually $main::x) and by that time it exists because the block has already been executed.

edit: It even looks like that BEGIN turns off certain warnings for this reason:

perl -MO=Deparse -wMstrict -e "{ package bla { *::x=\$a } }"
Name "main::x" used only once: possible typo at -e line 1.
...

[download]
perl -MO=Deparse -wMstrict -e "BEGIN { package bla { *::x=\$a } }"
# No problem

[download]

In reply to Re^2: Logic for importing and strict vars? by Veltro
in thread Logic for importing and strict vars? by haukex

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