Is this a perl bug, or is there some justification for the behavior?

perldoc -f require : ... demands that a library file be included if it hasn't already been included. The file is included via the do-FILE mechanism, which is essentially just a variety of "eval" ...

The second time require does not have to include library (again) thus:

#test.pl

for (1..2) {
    eval "require bar";
    print "attempt $_: ", ($@ ? "nok - $@" : "ok"), "\n";
}

#bar.pm

use Carp;
croak "loaded$/"

# STDOUT:

attempt 1: nok - loaded
        require bar.pm called at (eval 1) line 3
        eval 'require bar
;' called at test.pl line 3
Compilation failed in require at (eval 1) line 3.

attempt 2: ok

[download]
What's the correct way to load a module if and only if
it hasn't already been loaded successfully?

If a module cannot be loaded successfully the fisrt time why should we believe
that it will be loaded successfully the second time?


In reply to Re: Failed require looks like it succeeded by sh1tn
in thread Failed require looks like it succeeded by Anonymous Monk

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