Ruby 无法访问方法外的变量? [英] Ruby can not access variable outside the method?

问题描述

我是 Ruby 新手，看来 Ruby 确实支持在我想做某事时在刚刚访问的方法之外定义的变量:

I am new to Ruby, and it seems that Ruby does support variables defined outside the method being accessed just now when I want to do something:

template=<<MTEMP
#methodName#:function(){},
MTEMP
result="";
def generateMethods(mds)
  mds.each do |md|
    result+=template.gsub(/#methodName#/,md).to_s+"\n";
  end
  result;
end

puts generateMethods(['getName','getAge','setName','setAge'])

<小时>

当我尝试运行它时出现错误:

---

When I tried to run it I got the error:

main:Object (NameError) 的未定义局部变量或方法模板"

undefined local variable or method 'template' for main:Object (NameError)

似乎我无法访问 generateMethods 方法内部的 template 和 result 变量?

It seems that I can not access the template and result variable inner the generateMethods method?

为什么?

更新:

作用域的概念似乎与 javascript 中的概念不同?

It seems that the scope concept is differ from what is in the javascript?

var xx='xx';
function afun(){
  console.info(xx);
}

上面的代码会起作用.

推荐答案

generateMethods 函数中的 result 和 template 变量与那些在外部声明并且是该函数本地的.您可以使用 $ 将它们声明为全局变量:

The result and template variables inside the generateMethods function are different from the ones declared outside and are local to that function. You could declare them as global variables with $:

$template=<<MTEMP
#methodName#:function(){},
MTEMP
$result="";
def generateMethods(mds)
  mds.each do |md|
    $result+=$template.gsub(/#methodName#/,md).to_s+"\n";
  end
  $result;
end
puts generateMethods(['getName','getAge','setName','setAge'])

但是您使用此功能的目的是什么?我认为如果您能更详细地解释您的问题，还有一种更简洁的方法.

But what's your purpose with this function? I think there's a cleaner way to do this if you can explain your question more.

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