Accept where clause in an advanced function
As ansgar-wiechers stated in the above comment, you have to remove the outer scriptblock literal ({}):
$Fruits = @( @{ Name = 'Kiwi' Color = 'Green' } @{ Name = 'Banana' Color = 'Yellow' })Function Get-Stuff { Param ( [scriptblock]$Filter, [hashtable[]]$Collection ) # Subexpression removed. $Collection.Where($Filter)}Get-Stuff -Filter { $_.Name -eq 'Kiwi' } -Collection $Fruits