Listing 1: To-TimeSpan.ps1

# To-TimeSpan.ps1
# converts day:hour:minute:second notation time into seconds

# ------- BEGIN CALLOUT A -------
param([string]$Timespan = `
  $(Read-Host -Prompt "Enter a time span in [[[days:]hours:]minutes:]seconds format"),
  $Milliseconds = 0
)
# ------- END CALLOUT A -------

# ------- BEGIN CALLOUT B -------
$values = [System.Collections.ArrayList]$Timespan.Split(":")
# ------- END CALLOUT B -------

# ------- BEGIN CALLOUT C -------
while($values.Count -lt 4){$values.Insert(0, 0)}
# ------- END CALLOUT C -------

# ------- BEGIN CALLOUT D -------
$values.Insert(4, $Milliseconds)
# ------- END CALLOUT D -------

# ------- BEGIN CALLOUT E -------
New-Object system.timespan $values
# ------- END CALLOUT E -------