Limited set of reserved expressions:
is ⋅ it ⋅ be ⋅ at ⋅ on ⋅ to ⋅ as ⋅ that ⋅ this ⋅ unwrap ⋅ wrap ⋅ intro ⋅ empty ⋅ not ⋅ swap ⋅ pop ⋅ push ⋅ top
Generalized internal expressions:
identity ⋅ initial ⋅ terminal