Feature Request: Add .slice() method for strings and arrays

Summary of the new feature/enhancement

Add a .slice() method for strings and arrays similar to that of JavaScript. See: https://www.w3schools.com/jsref/jsref_slice_array.asp

For strings, this would provide a method to return the rightmost N characters of a string by using negative value. For example:

# Rightmost N existing solution
PS C:\ps1> $text = "ABCDEFG"
PS C:\ps1> $text.Substring($text.Length - 2)
FG

# Rightmost N characters with slice()
PS C:\ps1> "ABCDEFG".slice(-2)
FG

# Padding a month number with slice():
PS C:\ps1> ('0' + (get-Date).Month).slice(-2)
07

Below are a few additional examples of how slice() might work:

PS C:\ps1> "007".slice(-2)
07

PS C:\ps1> "ABCDEFG".slice(3)
DEFG

PS C:\ps1>  $fruits = @("Banana", "Orange", "Lemon", "Apple", "Mango")

PS C:\ps1> $fruits.slice(2)
Lemon

PS C:\ps1> $fruits.slice(2..4)
Lemon
Apple
Mango

PS C:\ps1> $fruits.slice(-2)
Apple

PS C:\ps1> $fruits.slice(-2..-1)
Apple
Mango

Proposed technical implementation details (optional)

Virtually all of the slice() functionality can be leveraged from the existing array code. The PowerShell code below serves as a simple example of how to define slice():

# String slice()
$stringMethod = @{
  MemberName = 'slice';
  MemberType = 'ScriptMethod';
  Value      = { param([int32] $t) $( if ($t -ge 0) {$this.substring($t)} else {$this.substring(($this.Length + $t))}) }	
  Force      = $true
}
Update-TypeData -TypeName 'string' @stringMethod

# System.Array slice()
$arrayMethod = @{
  MemberName = 'slice';
  MemberType = 'ScriptMethod';
  Value      = { param($t) $this[$t] }	
  Force      = $true
}
Update-TypeData -TypeName 'System.Array' @arrayMethod

This method is a convenience feature for those familiar with JavaScript and to provide a way to easily extract the rightmost characters of a string (the substring() method does not permit negative values).

[doctordns]

This is probably something that should not be done in PowerShell. Instead, file this issue against .Net itself.

[doctordns]

You miss the point. If this change is made in .net, it would just appear in PowerShell as if by magic. A new build targeted at an updated .net would just work with no effort by the team. Asking for it inside powershwll is just more work to adapt the string class. In my view, .net is the right place for such a method. Mileage will vary.