在没有空白“救援"块的情况下，让 Ruby 块/命令静默失败 [英] Having a Ruby block/command silently fail without a blank 'rescue' block

问题描述

说我想要运行一个调用，如果它失败了，也没什么大不了的；该程序可以毫无问题地继续.(我知道这通常是不好的做法，但想象一个假设的、快速的一次性脚本，而不是一个大型项目)

Say I want a call to be run, and if it fails, it's no big deal; the program can continue without a problem. (I know that this is generally bad practice, but imagine a hypothetical, quick one-off script, and not a large project)

我被教导这样做的方式是:

The way I've been taught to do this was:

begin
  thing_to_try
rescue
  # awkward blank rescue block
end
next_thing

当然，还有其他方法可以做到这一点，包括使用 ensure 和类似的东西.但是有没有办法让方法调用/块在没有混乱的空白块的情况下静默失败?

Of course, there are other ways to do this, including using ensure and things like that. But is there a way to get a method call/block to silently fail without a messy blank block?

推荐答案

这样的方法很有帮助.

def squelch(exception_to_ignore = StandardError, default_value = nil)
  yield
rescue Exception => e
  raise unless e.is_a?(exception_to_ignore)
  default_value
end

您可以在 class Object 中定义此方法以实现普遍可用性.

You might define this method inside class Object for universal availability.

然后你可以写:

squelch { foo } || squelch { bar }

采用这种方法的真正优势是您可以使用多行块，因为内联 rescue 只能用于单个语句.

The real advantage to having this approach is you can use multiline blocks, since inline rescue can only be used on a single statement.

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