Identifier

Function application

A binary type constructor which builds function types

Builds list types

A type variable standing for an arbitrary type. All type variables have a unique id, but names are only assigned lazily, when required.

Lambda abstraction

Let binding

An n-ary type constructor which builds a new type from old

Raised if the unification didn't happen

Raised if the type inference algorithm cannot infer types successfully

List

Rewrites builtin ast to airtight ast Checks for unsupported python syntax

Lambda with no args

Letrec binding

Raised if the type environment supplied for is incomplete

A list of expressions

converts the python ast to a lambda-like ast used for type inference