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powershellfunctional-programmingpowershell-2.0first-class-functions

Pass a function (with arguments) as a parameter in PowerShell

I've been successfully passing no-argument functions around in PowerShell using ScriptBlocks. However, I can't get this to work if the function has arguments. Is there a way to do this in PowerShell? (v2 preferably)

Function Add([int] $x, [int] $y)  
{ 
  return $x + $y 
}
Function Apply([scriptblock] $s)    
{ 
    write-host ($s.Invoke(1,2)) 
}

Then

Apply { Add }

writes 0 to the console. Apply does invoke Add, but doesn't pass any arguments in (i.e. uses the default [int] values of 0 and 0)

Solution

  • Ok, I found the answer here:

    I wanted ${function:Add} rather than { Add } in the call to Apply.