Test.Speculate.Expr.Ground

This module is part of Speculate.

Generate and evaluate ground values of expressions.

Documentation

grounds :: (Expr -> [[Expr]]) -> Expr -> [Expr]

List all possible valuations of an expression (potentially infinite). In pseudo-Haskell:

take 3 $ grounds (lookupTiers preludeInstances) ((x + x) + y)
  == [(0 + 0) + 0, (0 + 0) + 1, (1 + 1) + 0]

Note this function will return an empty list when a Listable instance is not found in the Instances list.

groundBinds :: (Expr -> [[Expr]]) -> Expr -> [Binds]

List all possible variable bindings to an expression

take 3 $ groundBinds (lookupTiers preludeInstances) ((x + x) + y)
  == [ [("x",0),("y",0)]
     , [("x",0),("y",1)]
     , [("x",1),("y",0)] ]

equal :: Instances -> Int -> Expr -> Expr -> Bool

Are two expressions equal for a given number of tests?

lessOrEqual :: Instances -> Int -> Expr -> Expr -> Bool

Are two expressions less-than-or-equal for a given number of tests?

less :: Instances -> Int -> Expr -> Expr -> Bool

Are two expressions less-than for a given number of tests?

inequal :: Instances -> Int -> Expr -> Expr -> Bool

Are two expressions inequal for *all* variable assignments? Note this is different than not . equal.

isTrue :: (Expr -> [Expr]) -> Expr -> Bool

Is a boolean expression true for all variable assignments?

isFalse :: (Expr -> [Expr]) -> Expr -> Bool

Is an expression ALWAYS false? This is *NOT* the same as not true.

condEqual :: Instances -> Int -> Expr -> Expr -> Expr -> Bool

Are two expressions equal under a given condition for a given number of tests?

condEqualM :: Instances -> Int -> Int -> Expr -> Expr -> Expr -> Bool

Are two expressions equal under a given condition for a given number of tests and a minimum amount of tests

trueRatio :: Instances -> Int -> Expr -> Ratio Int

Under a maximum number of tests, returns the ratio for which an expression holds true.