String eval compiles at runtime and will avoid the error in older perls (you'll have to move the declaration of $mem to avoid a scoping issue). 
my $var = '';
my $mem;
if($] > 5.007) {
    if( eval q{open ($mem, '>', \$var) } ) {print "Success\n"}
}
else {print "Ok\n"}

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In reply to Re: Compile time problem by FunkyMonk
in thread Compile time problem by syphilis

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