I'm not sure why that doesn't work. I will recommened against using the & notation if at all possible. The following works for me (cygwin 5.8). 

$foo=5;
sub has {print "ok\n"}
sub hasnt {print "no dice\n"}

eval "require $foo" ? has : hasnt

[download]

prints ok 

$foo="nosuchmodule";
sub has {print "ok\n"}
sub hasnt {print "no dice\n"}

eval "require $foo" ? has : hasnt

[download]

prints no dice

In reply to Re: Running a script if module is not installed. by roju
in thread Running a script if module is not installed by yoda54

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