Data.Express.Triexpr

This module is part of Express.

An experimental data structure for matching Exprs.

Warning (1): Take care when importing this module, the interface is experimental and may change at every minor version.

Warning (2): YMMV: Do not expect this to be faster than manually matching in a list, provisional experiments show that it can be slower depending on the set of expressions being matched.

This module should be imported qualified as it exports definitions called map, lookup, toList, fromList, insert and empty:

import Data.Express.Triexpr (Triexpr)
import qualified Data.Express.Triexpr as T

Documentation

data Triexpr a

A trie of Exprs.

In the representation, Nothing matches an App and Just Expr an expression.

Constructors

Triexpr [(Maybe Expr, Either (Triexpr a) (Expr, a))]

Instances

Eq a => Eq (Triexpr a)

Defined in Data.Express.Triexpr

Methods

(==) :: Triexpr a -> Triexpr a -> Bool

(/=) :: Triexpr a -> Triexpr a -> Bool

Ord a => Ord (Triexpr a)

Defined in Data.Express.Triexpr

Methods

compare :: Triexpr a -> Triexpr a -> Ordering

(<) :: Triexpr a -> Triexpr a -> Bool

(<=) :: Triexpr a -> Triexpr a -> Bool

(>) :: Triexpr a -> Triexpr a -> Bool

(>=) :: Triexpr a -> Triexpr a -> Bool

max :: Triexpr a -> Triexpr a -> Triexpr a

min :: Triexpr a -> Triexpr a -> Triexpr a

Show a => Show (Triexpr a)

Defined in Data.Express.Triexpr

Methods

showsPrec :: Int -> Triexpr a -> ShowS

show :: Triexpr a -> String

showList :: [Triexpr a] -> ShowS

empty :: Triexpr a

An empty Triexpr.

unit :: Expr -> a -> Triexpr a

Constructs a Triexpr encoding a single expression.

merge :: Triexpr a -> Triexpr a -> Triexpr a

Merges two Triexprs.

insert :: Expr -> a -> Triexpr a -> Triexpr a

Inserts an Expr into a Triexpr.

toList :: Triexpr a -> [(Expr, a)]

List all Expr stored in a Triexpr along with their associated values.

fromList :: [(Expr, a)] -> Triexpr a

Constructs a Triexpr form a list of key Exprs and associated values.

map :: (a -> b) -> Triexpr a -> Triexpr b

Maps a function to the stored values in a Triexpr.

lookup :: Expr -> Triexpr a -> [(Expr, [(Expr, Expr)], a)]

Performs a lookup in a Triexpr.