PowerShell：一种创建闭包的优雅方式 [英] PowerShell: an elegant way to create closures

问题描述

Keith Hill 向我解释说，块不是闭包，并从块创建闭包我必须调用方法。GetNewClosure（）。

Keith Hill explained me that blocks in PowerShell are not closures and that to create closures from blocks I have to call method .GetNewClosure().

从块创建闭包？ （例如创建包装函数，别名？，...）

Is there any elegant way to create closures from blocks? (e.g. create a wrapping function, an alias?, ...)

示例：

{ block }
${ closure } # ???

推荐答案

您可以创建一个函数， GetNewClosure并返回闭包。必须使用点运算符调用此函数，例如：

You could create a function that takes a scriptblock, calls GetNewClosure and returns the closure. It is essential that you call this function using the dot operator e.g.:

function =>([scriptblock]$_sb_)
{
    $_sb_.GetNewClosure()
}

function A($block) 
{
    B (. => {Write-Host 2; &$block})
}

function B($block) {Write-Host 1;&$block}

A {Write-Host 3}

不确定这比在脚本块上调用GetNewClosure 。注意，你可以选择一些其他名称的功能。我正在寻找更像C＃lambdas的东西。

Not sure this is much better than just calling GetNewClosure() on the scriptblock though. Note you can pick some other name for the function. I was going for something more like C# lambdas.

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