Internal types - githwxi/ATS-Postiats GitHub Wiki
Internal types are introduced in the file pats_staexp2.sats, and having a better understanding of how these types relate to actual ATS types will be helpful in debugging.
S2Eapp- an application term.S2Ecst- a type constant (for instance, int, bool, list, etc.)S2Eeff- function effects.S2Eexi- an existentially quantified type.S2Eint- machine precision integer.S2Eintinf- infinite precision integer; commonly used for integer sorts in most compiled versions of atsopt (patsopt).S2Evar- a (typically universally quantified) variable.S2Etop(knd=0; T)meansT?S2Etop(knd=1; T)meansT?!S2EVar- an (existentially quantified) unification variable introduced by the typechecker.S2RTBASpre(s)- predicative sort s.S2RTBASimp(1; s)- impredicative sort s.S2RTfun- refers to a functional sort.