How to stop Powershell insisting on one dash in parameters?

Question

It seems that somebody has subtly changed the way that parameter switches are parsed on powershell. On some machines "split-path c:\x\y --parent" works. On some it fails. Can anyone tell me a) what causes the difference and b) how can I stop it?

Answer 1

Switch parameters should work in the same way in both V1 and V2 (that means -parent is the right syntax).

In your case --parent should be bound to an parameter as a string. It should not be interpreted as a switch. You can test the binding via Trace-Command

Trace-Command parameterbinding -Expression { split-path c:\x\y --parent} -PSHost

Further info:

Considering --: every string behind -- is interpreted as argument, no matter if it looks like a switch.

[14]: function test { 
    param([switch]$sw, [string]$str) 
    write-host switch is $sw
    write-host str is $str 
}
[15]: test 1
switch is False
str is 1
[16]: test -sw
switch is True
str is
[17]: test -- -sw
switch is False
str is -sw