PSCustomObject not liking inline if statements in NoteProperty's value - powershell

Question

Not sure if I am doing something stupid or if it is a "feature" of PowerShell.
Taking the following example code snippet:
[array]$Strings = #(
"This is an example string"
"This another example string test"
"This is something else fun"
"Not in list"
)
$oData = #()
Foreach($string in $strings)
{
$split = if($string.substring(0,4) -eq "This"){$String.Split(" ")}
$oData += [pscustomobject]#{
Part1 = $Split[0]
Part2 = $Split[1]
Part3 = $Split[2]
Part4 = $split[3]
Part5 = $split[4]
}
}
$oData
This throws the error Cannot index into a null array which is expected as the fourth member of the array "Strings" is not in the list so it cannot be indexed. Fair enough. To mitigate this, I though of the following modification:
$oData = #()
Foreach($string in $strings)
{
$split = if($string.substring(0,4) -eq "This"){$String.Split(" ")}
$oData += [pscustomobject]#{
Part1 = if($Split){$split[0]}
}
}
Which works, until I go to add Part2 to the object:
$oData = #()
Foreach($string in $strings)
{
$split = if($string.substring(0,4) -eq "This"){$String.Split(" ")}
$oData += [pscustomobject]#{
Part1 = if($Split){$split[0]}
Part2 = if($Split){$split[1]}
}
}
ISE underlines "Part2" with the message Unexpected token 'Part2' in expression or statement and the last curly brace of "Part1" has a an underline with the message The hash literal was incomplete.
When I run the script, the error is:
At line:13 char:38
+ Part1 = if($Split){$split[0]}
+ ~
The hash literal was incomplete.
At line:14 char:9
+ Part2 = if($Split){$split[1]}
+ ~~~~~
Unexpected token 'Part2' in expression or statement.
At line:16 char:1
+ }
+ ~
Unexpected token '}' in expression or statement.
+ CategoryInfo : ParserError: (:) [], ParentContainsErrorRecordException
+ FullyQualifiedErrorId : IncompleteHashLiteral
To me, it seems a valid way to handle the null array and I'm sure I've used if statements in PSCustomObject values before.
I can work around the problem as I've done in the past when I've come across this problem before but I was wondering if anyone can shed light on why PowerShell doesn't like it.

Answer 1

I'm not entirely certain of the reason, but if you end your lines (all but the last so just the first one here) with semicolon ; it works fine. You can of course end all of them in ; for consistency as well.
I speculate it has something to do with the way the parser handles these, and it just doesn't know that the expression has ended for sure, whether it should know or not.
$oData += [pscustomobject]#{
Part1 = if($Split){$split[0]};
Part2 = if($Split){$split[1]}
}

Answer 2

The easy answer seems to be to add the else. As in:
$oData = #()
Foreach($string in $strings)
{
$split = if($string.substring(0,4) -eq "This"){$String.Split(" ")}
$oData += [pscustomobject]#{
Part1 = if($Split){$split[0]}else{$null}
Part2 = if($Split){$split[1]}else{$null}
Part3 = if($Split){$split[2]}else{$null}
Part4 = if($Split){$split[3]}else{$null}
Part5 = if($Split){$split[4]}else{$null}
}
}
Strange that PS is happy with:
if($something -eq $true)
{
"Hello"
}
Without the else or elseif part outside of the [pscustomobject].