> perl -wle "sub foo { print 'In foo' }; my $func='foo'; &$func"
In foo

##</code><code>##

> perl -Mstrict -wle "sub foo { print 'In foo' }; my $func='foo'; &$func"
Can't use string ("foo") as a subroutine ref while "strict refs" in use at -e line 1.