I have a question about eval.

Given the general error handling construct:

perl -e '$foo = "foo"; eval { $bar = $foo; } or do { die "Error: $@"; };'

This works as expected (IE does not die) for any value of $foo except undef or empty string. If $foo is undef or empty string, $@ gets set to empty string and the or do {...} block is executed. This seems like the Wrong Thing to me -- assigning either undef or an empty string to a scalar is a valid statement, therefore $@ should not get set

It's easy enough to work around this (mis-)behavior by putting a no-op at the end of the eval block:

perl -e '$foo = undef; eval { $bar = $foo; 1; } or do { die "Error: $@"; };'

Still, I'm curious as to why it works this way. It doesn't seem to be consistent.

In reply to Eval, assignments, and empty string/undef by jpepersack

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