Function default_of 

pub const fn default_of(specs: &[ParamSpec], name: &str) -> f32

The default name is declared with, resolved at compile time.

This is what makes a scene’s DEFAULT_* constant and its ParamSpec one number rather than two copies of one: the constant is defined as a call to this, so a default changed in the spec changes what reset_params applies, and the generated table cannot state a value the engine does not use.

The linear scan costs nothing — it never runs at runtime — and a name with no spec is a compile error, because a const-eval panic is.