PowerShell: Input Parameter [Array] element automatically/incorrectly converts to wrong datatype

Question

PowerShell's automatically presuming that the value ' 9e9 ' (in the COMMAND below) is an integer; since the value isn't surrounded by quotes.

I'm looking for any clever way to either treat all array elements/values as strings (no matter what) or force PowerShell to treat any values with an 'e' character in the middle, as a string... or, any other possible way before the its automatically casted as an integer WITHOUT having to surround the value with quotes .

COMMAND:

Get-Input -var 9e9, ba7

CODE:

function Get-Input {

    [CmdletBinding()]
    param(
        [array[]]$Vars
    )

    $Var = $Vars[0]

    write-output $Var
}

**** UPDATE ****

TessellatingHeckler has the best solution at the end of his answer. I just made one minor modification to strip spaces. I still think it's all PowerShell's fault. j/k. I really appreciate the time TessellatingHeckler to break it all down and still provide a sensible solution. Thanks TessellatingHeckler!

COMMAND:

Get-Input -vars "9e9, ba7"

NEW CODE:

function Get-Input {

    [CmdletBinding()]
    param(
        [string[]]$Vars
    )

    $Vars = $Vars.replace(' ', "")
    $Vars = $Vars.split(",")

    $Var = $Vars[0]

    write-output $Var

}

Answer 1

PowerShell's automatically presuming that the value '9e9' (in the COMMAND below) is an integer; since the value isn't surrounded by quotes.

Admittedly, that's got me a bit annoyed at the 'blame the tool I like' wording; 'Presume': "be arrogant or impertinent enough to do something"

It's in the language spec (section 2.3.5.12 Real Literals) that "number e number" is a way of writing a real number ([double]).

That's not PowerShell presuming anything, you're telling it to interpret it that way by using the "this is a number" syntax instead of "this is a string" syntax (quotes).

Anyway.

I'm looking for any clever way to either treat all array elements/values as strings (no matter what) [..]

before it's automatically casted as an integer WITHOUT having to surround the value with quotes.

The array value is 9000000000, if you could force it to be a string, the string would be "9000000000" - ie at that point, it's already too late to change it back.

In the same way that 1/2 means 0.5 , you can't convert 0.5 to a string and expect to get 1/2 back out.

It's not being cast as a number, it is a number in the PowerShell language.

That sounds a bit like I'm repeating the same point, but the significance this time is that anything you do in the function, such as setting the parameter type to [string[]] is too late to make a difference, the array already has the undesired interpretation in it. Any intervention would have to happen sooner.

force PowerShell to treat any values with an 'e' character in the middle, as a string... or, any other possible way

As it scans Get-Input -var 9e9, ba7 it reads a GenericToken for 'Get-Input' which is going to turn into a command.

It hits '-' and starts reading an operator or a parameter, reads 'var' up to the space and doesn't match an operator ('-eq', '-gt', etc) so treats it as a parameter.

It reads the '9' and starts reading a number.

There's only two ways out of this - if the number is valid, it's read as a number. That happens now and you don't want it.

If the number is not valid, eg 7z.exe starts with a number, but is not one, then it fails, backtracks out, and treats it as a GenericToken for an argument.

So you could tack on something else to force it to be a string 9e9z . But you can't write '9e9' and have it become a string without quotes.

About the only thing you can do is use something else as a separator (not a comma) which would force the entire argument to be one string - that means no spaces either - and then split it yourself into text pieces inside the function.

function Get-Input {

    [CmdletBinding()]
    param(
        [string]$VarsText
    )

    $Vars = $VarsText.Split('.')

    $Var = $Vars[0]
    write-output $Var
}

Get-Input 9e9.bab

Which will only confuse everyone, and would likely read more helpfully if you did

Get-Input "9e9,bab,..." 

and used the comma everyone is familiar with, inside one quoted string.