Test.Extrapolate.Speculation

This module is part of Extrapolate, a library for generalization of counter-examples.

This defines utilities for speculation about side conditions.

You are probably better off importing Test.Extrapolate.

Documentation

theoryAndReprConds :: (Expr -> Expr -> Bool) -> Int -> [[Expr]] -> (Thy, [Expr])

data Thy

Instances

Eq Thy

This instance is as efficient as it gets, but, this function will not detect equality when rules and equations are in a different order (or repeated). See |==|.

Defined in Test.Speculate.Reason

Methods

(==) :: Thy -> Thy -> Bool

(/=) :: Thy -> Thy -> Bool

data Expr

Values of type Expr represent objects or applications between objects. Each object is encapsulated together with its type and string representation. Values encoded in Exprs are always monomorphic.

An Expr can be constructed using:

• val, for values that are Show instances;
• value, for values that are not Show instances, like functions;
• :$, for applications between Exprs.

> val False
False :: Bool

> value "not" not :$ val False
not False :: Bool

An Expr can be evaluated using evaluate, eval or evl.

> evl $ val (1 :: Int) :: Int
1

> evaluate $ val (1 :: Int) :: Maybe Bool
Nothing

> eval 'a' (val 'b')
'b'

Showing a value of type Expr will return a pretty-printed representation of the expression together with its type.

> show (value "not" not :$ val False)
"not False :: Bool"

Expr is like Dynamic but has support for applications and variables (:$, var).

The var underscore convention: Functions that manipulate Exprs usually follow the convention where a value whose String representation starts with '_' represents a variable.

Instances

Eq Expr

O(n). Does not evaluate values when comparing, but rather uses their representation as strings and their types.

This instance works for ill-typed expressions.

Defined in Data.Express.Core

Methods

(==) :: Expr -> Expr -> Bool

(/=) :: Expr -> Expr -> Bool

Ord Expr

O(n). Does not evaluate values when comparing, but rather uses their representation as strings and their types.

This instance works for ill-typed expressions.

Expressions come first when they have smaller complexity (compareComplexity) or when they come first lexicographically (compareLexicographically).

Defined in Data.Express.Core

Methods

compare :: Expr -> Expr -> Ordering

(<) :: Expr -> Expr -> Bool

(<=) :: Expr -> Expr -> Bool

(>) :: Expr -> Expr -> Bool

(>=) :: Expr -> Expr -> Bool

max :: Expr -> Expr -> Expr

min :: Expr -> Expr -> Expr

Show Expr

Shows Exprs with their types.

> show (value "not" not :$ val False)
"not False :: Bool"

Defined in Data.Express.Core

Methods

showsPrec :: Int -> Expr -> ShowS

show :: Expr -> String

showList :: [Expr] -> ShowS

classesFromSchemasAndVariables :: Thy -> [Expr] -> [Expr] -> [Class Expr]