Eval package:clash-lib

The monad of partial evaluation. The inner monad is IO, as primitive evaluation can attempt to evaluate IO actions.

An evaluator is a collection of basic building blocks which are used to define partial evaluation. In this implementation, it consists of two types of function:

• steps, which applies the reduction realtion to the current term
• unwindings, which pop the stack and evaluate the stack frame

Variants of these functions also exist for evalauting primitive operations. This is because there may be multiple frontends to the compiler which can reuse a common step and unwind, but have different primitives.

An evaluator for Clash core. This consists of two functions: one to evaluate a term to weak-head normal form (WHNF) and another to recursively evaluate sub-terms to obtain beta-normal eta-long form (NF).

Render a blackbox given its context. Renders _just_ the blackbox, not any corresponding includes, libraries, and so forth.

The main API of the partial evaluator. This exposes the main functions needed to call the evaluator, and the type of evaluators. A concrete implementation of an evaluator is required to use this module: this can be imported from the library for the compiler front-end, e.g. Clash.GHC.PartialEval in clash-ghc.

Evaluate an action in the partial evaluator, returning the result, and the final state of the global environment.

Set the threshold for maximum unfolding depth in the evaluator. A value of zero means no potentially non-terminating binding is unfolded. Command line flag: -fclash-evaluator-fuel-limit

Hardcoded evaluator for WHNF (old evaluator)

Hardcoded evaluator for partial evaluation