tryfinally-4.ps1

# ContextLogger.psm1

$ContextStack = [System.Collections.Stack]::new()

function Invoke-InContext {
    Param(
        [ValidateNotNullOrEmpty()]
        [string] $Name,
        [ValidateNotNullOrEmpty()]
        [scriptblock] $ScriptBlock
    )

    Write-Log "<$Name>"
    $ContextStack.Push($Name)
    $start = Get-Date
    & $ScriptBlock | % {Write-Log $_} # format each line of output
    $stop = Get-Date
    $ContextStack.Pop()
    Write-Log "</$Name> $($stop - $start)"
}

function Write-Log {
    Param(
        [ValidateNotNullOrEmpty()]
        [string] $Message
    )

    $timestamp = Get-Date -Format 'MM/dd hh:mm:ss'
    $contextArray = $ContextStack.ToArray()
    [array]::Reverse($contextArray)
    Write-Output "$timestamp [$($contextArray -join ">")] $Message"
}