A Practical Subtyping System For Erlang

We present a type system for the programming language Erlang. The type system supports subtyping and declarationfree recursive types, using subtyping constraints. Our system is similar to one explored by Aiken and Wimmers, though it sacrifices expressive power in favour of simplicity. We cover our techniques for type inference, type simplification, and checking when an inferred type conforms to a user-supplied type signature, and report on early experience with our prototype.

• Type: Conference
• Year: 1997
• Where: ICFP
• Authors: Simon Marlow, Philip Wadler
• Keywords: ICFP 1997, Inferred Type Conforms, Programming Languages, Type System, User-supplied Type Signature