Yeah, you read that title correctly. Or did you? You might want to double-check; I had to write it a few times.
I did that thing where I authored some PowerShell code and I don’t know what to do with it. While it was written during some updates to a common function template, I’m not yet sure it’ll be implemented there. Therefore, I figured I’d share it. Additionally, this will give me a place to store it, in case I do use it. Some day you may ask yourself, can I create a function that creates a global function, that contains other functions? Yes. Today, I intend better help answer that question and include an example.
All this said I’m not here to explain why you might want to do this. Again, I’m not even sure if I’ll need this. So Internet and you, it’s yours. Edit: Some time has passed since I wrote this opening, so yes, I’ll be using this in production.
I have a function template that I use when writing any new function(s). Its number one goal is to ensure that all my functions, or tools, include identical logging. It’s identical, whether it’s written to the screen, to a file, or to both. I feel like I’ve written that before.
When the function is complete, and it’s written a log file, I have a global function that is created, too. This allows you to quickly open the log file, open just the location of the log file, or read in the contents of the most recently created log file and create an object from each line. If a single function is created, then the user isn’t required to remember more than a single function name. Sure, they might have to remember the parameter values for the single functi– okay, no they wouldn’t. They can tab through those.
Code Example
Function Show-FunctionTemplate {
'You''re inside the Function Template (1st).'
Function Global:New-FtFunction {
Param (
[Parameter()]
[ValidateSet('1','2','6')]
[array]$Function
) # End Param.
Switch ($Function) {
'1' {Function Test-One {'Test-One'}; Test-One}
'2' {Function Test-Two {'Test-Two'}; Test-Two}
'6' {Function Test-Six {'Test-Six'}; Test-Six}
} # End Switch.
} # End Function: New-FtFunction.
'You''re inside the Function Template (2nd).'
} # End Function: Show-FunctionTemplate
Show-FunctionTemplate
New-FtFunction
New-FtFunction -Function 1
New-FtFunction -Function 1,2
New-FtFunction -Function 1,2,6
Discussion
The overall goal in this code is that we’ve created a function named Show-FunctionTemplate, in our local, and in this case, global scope. Done.
Inside this function (when it’s invoked), we echo a couple of statements about being inside the function. Additionally, and in between those two statements, we create a second global function named, New-FtFunction. When Show-FunctionTemplate is done executing, New-FtFunction can then be invoked.
When the New-FtFunction is invoked it won’t do anything unless one of the parameter values that it’s expecting is included. In the above code sample, I’ve included some examples. The below image shows the output returned from executing these.
Perhaps it should be noted, but the most nested of functions, both define the function and invoke it — one right after the other. But in obvious news now, I can do it. I can make a (global) function, make a global function responsible for making and invoking other functions. I think this is going into my function template. I really do. Edit: It did.