ghc-7.2.2: The GHC API

Rules

Contents

Description

Functions for collecting together and applying rewrite rules to a module. The CoreRule datatype itself is declared elsewhere.

Synopsis

RuleBase

type RuleBase = NameEnv [CoreRule]Source

Gathers a collection of CoreRules. Maps (the name of) an Id to its rules

Constructing

Checking rule applications

ruleCheckProgramSource

Arguments

:: CompilerPhase

Rule activation test

-> String

Rule pattern

-> RuleBase

Database of rules

-> [CoreBind]

Bindings to check in

-> SDoc

Resulting check message

Report partial matches for rules beginning with the specified string for the purposes of error reporting

Manipulating SpecInfo rules

mkSpecInfo :: [CoreRule] -> SpecInfoSource

Make a SpecInfo containing a number of CoreRules, suitable for putting into an IdInfo

Misc. CoreRule helpers

rulesOfBinds :: [CoreBind] -> [CoreRule]Source

Gather all the rules for locally bound identifiers from the supplied bindings

lookupRule :: (Activation -> Bool) -> IdUnfoldingFun -> InScopeSet -> Id -> [CoreExpr] -> [CoreRule] -> Maybe (CoreRule, CoreExpr)Source

The main rule matching function. Attempts to apply all (active) supplied rules to this instance of an application in a given context, returning the rule applied and the resulting expression if successful.

mkRule :: Bool -> Bool -> RuleName -> Activation -> Name -> [CoreBndr] -> [CoreExpr] -> CoreExpr -> CoreRuleSource

Used to make CoreRule for an Id defined in the module being compiled. See also CoreRule

roughTopNames :: [CoreExpr] -> [Maybe Name]Source

Find the "top" free names of several expressions. Such names are either:

  1. The function finally being applied to in an application chain (if that name is a GlobalId: see Var), or
  2. The TyCon if the expression is a Type

This is used for the fast-match-check for rules; if the top names don't match, the rest can't