EventCodes is a member of the APLTree library. The library is a collection of classes etc. that aim to support the Dyalog APL programmer. Search GitHub for "apltree" and you will find solutions to many every-day problems Dyalog APL programmers might have to solve.
Dyalog uses numbers to represent errors. Those errors are accessible via
⎕EN. However, when one wants to specify an error with a
:Trap or a
⎕TRAP statement then one must use integers.
Although a seasoned programmer will over time memorize the most important error numbers, the unusual ones will escape her, not to mention newbies.
There is a better solution to this: using symbolic names which are effectively constants (strictly speaking read-only variables) carrying the integer. That's what the
EventCode class is for: it offers symbolic names for all trappable events up to and including version 17.0.
EventCodes.DEADLOCK 1008 EventCodes.GetName 1008 DEADLOCK EventCodes.List'T' TIMEOUT 1006 TRANSLATION_ERROR 92 TRAP_ERROR 84 ⍴EventCodes.List'' 53 2