07-21-2023, 05:41 PM
PowerShell does pipes awkwardkly. To work around the return value problem and save the pipeline for real data, pass the function a value by reference, that is, an array. The array can be loaded with the value you wish to return. Here's a simple example:
# tp.ps1
# test passed parameters
# show that arrays are passed by reference, and can be used to provide
# return values outside the pipeline
function doprint
{
process { write-output "value now: $psitem" }
}
function recurse($thing, $rtx)
{
$thing++
if($thing -lt 20) {
if($thing -eq 15) { $rtx[0] = $thing }
write-output $thing | doprint
recurse $thing $rtx
}
}
j=0
$rtv=@(4)
recurse $j $rtv
write-output $rtv[0]
# tp.ps1
# test passed parameters
# show that arrays are passed by reference, and can be used to provide
# return values outside the pipeline
function doprint
{
process { write-output "value now: $psitem" }
}
function recurse($thing, $rtx)
{
$thing++
if($thing -lt 20) {
if($thing -eq 15) { $rtx[0] = $thing }
write-output $thing | doprint
recurse $thing $rtx
}
}
j=0
$rtv=@(4)
recurse $j $rtv
write-output $rtv[0]