phasers PRE

Documentation for phasers PRE, assembled from the following types:

language documentation Phasers

From Phasers

(Phasers) phasers PRE

Asserts a precondition at every block entry. Runs before the ENTER phase.

PRE phasers fire off before any ENTER or FIRST.

The exceptions thrown by failing PRE and POST phasers cannot be caught by a CATCH in the same block, which implies that POST phaser are not run if a PRE phaser fails.