ruby - Why do I get "undefined method `start_with?'"?

Question

I get:

undefined method 'start_with?' for "-f":String (NoMethodError)

At this line:

if arg.start_with?("-v")

This worked on a different machine apparently so I'm assuming it could be a problem with my Ruby installation. Any ideas?

Answer 1

String#start_with?在 Ruby 1.8.7 中引入。您显然使用的是较早的版本，这（可悲）并不少见，但 1.8 系列即将退役，您应该考虑升级。

String#start_with?我在1.8.6 文档中找不到任何引用，但它存在于1.8.7 文档中。