convenience version of `type.default` for effect values whose type is exactly the effect type (i.e., the value type does not inherit from the effect type).
set default instance for effect type `effect.this` to value `effect.this`.
NYI: UNDER DEVELOPMENT: See type.default
0.094dev (2025-06-18 15:08:51 GIT hash 89cffc23ae669b0898a5564fefbf793fcb8e5ca7 built by fridi@fzen)
exactly the effect type (i.e., the value type does not inherit
from the effect type).
set default instance for effect type `effect.this` to value `effect.this`.
NYI: UNDER DEVELOPMENT: See type.default