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Visibility Rules

Rules that enforce explicit access modifier declarations.

Rules​

RuleDefaultEffect
require_class_explicit_visibilitytrueEvery class must declare public or private
require_property_explicit_visibilitytrueEvery field and method must declare public or private

require_class_explicit_visibility = true​

Every class declaration must include an access modifier:

// ❌ Rejected — no visibility
Player class { }

// ✅ Required
Player public class { }
morphc: error: Class 'Player' must explicitly declare visibility
(public/private).
For agents: Declare class visibility explicitly:
`public Player is class { ... }`.

require_property_explicit_visibility = true​

Every field and method inside a class must have public or private:

// ❌ Rejected — implicit visibility
Player public class {
    health is 100;
    Run method() { }
}

// ✅ Required — explicit visibility
Player public class {
    health private is 100 as int;
    Run public method() { }
}
morphc: error: Class member 'Player.health' must explicitly declare
visibility (public/private).
For agents: Add `public` or `private` before class fields and methods.

Why These Rules Matter​

Implicit visibility is a common source of bugs and security issues:

  • A field accidentally exposed as public can be mutated from anywhere
  • An internal method accidentally public becomes part of the API contract

For AI agents, this is critical — they tend to forget access modifiers, which can accidentally expose internal implementation details.

Next Steps​