为什么在Perl中的字符串插值期间,变量名后跟下划线未正确计算？
- my $i = 3;
- print "i = $i\n"; # works,prints "i = 3"
- print "_i = _$i\n"; # works,prints "_i = _3"
- print "i_ = $i_\n"; # FAILS,prints "i_ = "
- print "_i_ = _$i_\n"; # sort of works,prints "_i_ = _"