My function builds a representation of a table as a PSCustomObject. It has a title, an array of column headers, and a [System.Collection.Generic.List][string] of rows:

function Create-ConfluenceTable{
    param(
        [Parameter(mandatory=$true)][string]$Title,
        [Parameter(mandatory=$true)][string[]]$Columns
    )

    $rows = [System.Collections.Generic.List[string]]::new()

    $t = [PSCustomObject]@{
        Title = $Title;
        Columns = $Columns;
        Rows = $rows
    }

    return $t
}

I then have a pipeline-aware function for adding rows to the table.

function AddRow {
    param(
        [Parameter(mandatory,ValueFromPipeline)]$ConfluenceTable,
        [Parameter(mandatory=$true)][string[]]$RowValues
    )

    process
    {
        foreach($rv in $RowValues) {
            $ConfluenceTable.Rows.Add($rv)
        }
    }
}

When I create the table and then try to pass values to it, I can’t get any string variables to correctly resolve. When I run this code…

$bar="https://example.com"
$ct = Create-ConfluenceTable -title "URLs" -Columns {"Type","Url"}
$ct | AddRow -RowValues {"Foo",$bar}
$ct

…my output is:

Title Columns        Rows        
----- -------        ----        
URLs  {"Type","Url"} {"Foo",$bar}

What I would like to see is:

Title Columns        Rows        
----- -------        ----        
URLs  {"Type","Url"} {"Foo","https://example.com"}