perl - perl require 语句有必要吗？

Question

require 5.00503;

以上 perl 语句要求版本为 5.00503。我很好奇如果 perl 程序中不包含上述语句会发生什么。

Answer 1

如果您指定的版本高于 Perl 解释器的版本，则会引发异常。

因此，当您使用 Perl 的某些功能时，需要解释器版本高于某个版本。

来自perldoc:require :

VERSION may be either a numeric argument such as 5.006, which will be compared to $] , or a literal of the form v5.6.1, which will be compared to $^V (aka $PERL_VERSION). An exception is raised if VERSION is greater than the version of the current Perl interpreter. Compare with use, which can do a similar check at compile time.