在Ruby中未定义变量 [英] Undefine variable in Ruby

问题描述

假设我使用的是irb，然后键入a = 5.如何删除a的定义，以便键入a会返回NameError?

Let's say I'm using irb, and type a = 5. How do I remove the definition of a so that typing a returns a NameError?

某些情况:稍后我要这样做:

Some context: later I want to do this:

context = Proc.new{}.binding
context.eval 'a = 5'
context.eval 'undef a'  # though this doesn't work.

推荐答案

有 remove_instance_variable 和 remove_const 方法，但当前没有等效的局部变量.

There are remove_class_variable, remove_instance_variable and remove_const methods but there is currently no equivalent for local variables.

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