PR# 19881 New PREDICATE feature:converse or item_not

Problem Report Summary
Submitter: martin-east
Category: EiffelBase
Priority: Low
Date: 2023/05/20
Class: Feature Request
Severity: Non-critical
Number: 19881
Release: 22.12
Confidential: No
Status: Analyzed
Environment: Any
Synopsis: New PREDICATE feature:converse or item_not

I would appreciate a function (suggested name: converse) in PREDICATE that returns a PREDICATE that returns the boolean inverse of the result of calling the current PREDICATE. 

Alternatively, a feature item_not in PREDICATE that returns a boolean not of item.

I think one or the other could reduce the need for inline agents in some situations and might also improve run-time efficiency for such calls

To Reproduce

Problem Report Interactions
From:jfiat_es    Date:2023/06/07    Status: Analyzed    Download   
Dear Martin,

I invite you to experiment on your side, and then to submit via this feature request entry, the new code for PREDICATE.
Then we will see if we integrate that change in PREDICATE.