Derive Macro Clip 

#[derive(Clip)]
{
    // Attributes available to this derive:
    #[clip]
}

Derives Clip for a vocabulary of the clips a mesh is posed by: each fieldless variant (and a unit struct) is named by what it is called in code, or by #[clip("...")] when the loaded animation name cannot be written as one — repeat the attribute for other spellings. The variants are numbered in order.

A variant with fields fails to compile: a clip is a plain name.