Groovy：闭包或方法 [英] Groovy : Closures or Methods
问题描述
我已经习惯使用Closures，我可以代替常规方法，即使我不需要访问自由变量。所以，我将使用这个：
I've got into the habit of using Closures everywhere I can in place of regular methods, even when I don't need access to free variables. So, I will use this:
def addNumbers = {left，right - left + right}
..而不是这样：
def addNumbers（left，right）{left + right}
这是不好的做法吗？
谢谢！
推荐答案
我只使用闭包，我需要它们，即我默认使用方法。我这样做是因为
I only use closures where I need them, i.e. I use methods by default. I do this because
-
方法比闭包更简单。闭包有一个委托，保留对在创建时在其本地作用域中的变量的访问（所谓的自由变量）。默认情况下，闭包中的方法调用由以下方式调用：
Methods are simpler than closures. Closures have a delegate, an owner, retain access to variables that were in their local scope when created (what you call "free variables"). By default method calls within a closure are resolved by:
- 关闭自己
- li>
- 关闭委托
在运行时更改，并且一个闭包的委托也可以更改为任何对象。
But this order can be changed at runtime, and a closure's delegate can also be changed to any object.
所有这些因素组合可以使一些使用闭包的代码非常棘手，如果你不需要任何这种复杂性，我宁愿通过使用一个方法消除它
All of these factors combined can make some code that uses closures very tricky to grok, so if you don't need any of this complexity I prefer to eliminate it by using a method instead
- .class文件是我只有零个证据支持一个声明，一个常规的方法比闭包更有效，但我有怀疑。至少，很多类可能会导致你耗尽PermGen的内存空间 - 这经常发生在我频繁，直到我把我的PermGen空间到大约200MB
- A .class file is generated for each closure defined in Groovy. I have exactly zero evidence to support a claim that a regular method is more performant than a closure, but I have suspicions. At the very least, a lot of classes may cause you to run out of PermGen memory space - this used to happen to me frequently until I raised my PermGen space to about 200MB
我不知道我倡导的做法（默认情况下使用方法，只在需要时使用闭包）被广泛认为是最佳实践，所以我很想知道其他人认为。
I have no idea whether the practice I'm advocating (use methods by default and closures only when you need them) is widely considered a "best practice", so I'm curious to hear what others think.
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