Proposal: `.not` as a Method-Based Negation Operator

[MatheusRich]

This proposal defines not as a regular method, not a keyword or special operator. It enables fluent, English-like syntax while avoiding contextual grammar rules or parser complexity.

Behavior

• .not is a method defined on booleans and objects that implement truthiness.
• When called, it returns the logical negation of the receiver (!self or !to_bool).
• It works in any context where boolean negation is expected: conditionals, assignments, expressions, etc.
• It can also be chained fluently to negate the result of a boolean-returning method call.

Examples

if user.not().logged_in?()     # reads like: "if user not logged in"
if enabled.not()               # negates the boolean value but it's better written as `if not().enabled` with an implicit self at the top level
flag = disabled.not()          # assigns the inverse of `disabled`

This avoids the need for a not keyword or ! operator entirely, and eliminates the awkwardness of unless, which many developers mentally rewrite as if not.

Benefits

• ✅ Reads naturally in fluent method chains
• ✅ No special grammar or contextual keywords
• ✅ Uniform: .not() is just a method
• ✅ Works consistently in all boolean contexts
• ✅ Avoids unless, !, and if not rewrites