Someone as asking about Traps vs Try/Catch and Jason Shirk (PowerShell developer) gave a nice concise and precise answer that I thought I would share with you:

• Trap:
• Designed for admins
• V1 and V2
• Introduces a new scope
• Is “global”, meaning it applies to all code in the same scope, before or after.
• Does not support rethrow (an empty throw statement throws a special RuntimeException with the message “ScriptHalted”)
• Try/Catch
• Designed for developers
• V2 only
• Does not introduce a new scope
• Guarded code is in the try statement block, not the entire scope containing the try statement
• Supports finally
• Supports rethrowing exceptions

Enjoy!

Jeffrey Snover [MSFT]
Distinguished Engineer
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