Check out the $@ variable which contains the contents of any errors incurred while running eval() 
# foo.pm
package foo;

sub 123 { print "this is an invalid sub name" }

qq(The End);

# script.pl
eval "require foo;";
die("ack - $@") if $@;

__output__

ack - syntax error at foo.pm line 5, near "qq(The End)"
Compilation failed in require at (eval 1) line 1.

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HTH

_________
broquaint

In reply to Re: Testing sub-module existence by broquaint
in thread Testing sub-module existence by loosifer

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