https://github.com/athanclark/pred-trie

predicative lookup container
https://github.com/athanclark/pred-trie

haskell lookup parametric-polymorphism predicates trie

Last synced: 3 days ago
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predicative lookup container

• Host: GitHub
• URL: https://github.com/athanclark/pred-trie
• Owner: athanclark
• License: bsd-3-clause
• Created: 2015-04-18T00:28:02.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2018-11-20T23:35:29.000Z (almost 6 years ago)
• Last Synced: 2024-04-26T07:02:45.194Z (7 months ago)
• Topics: haskell, lookup, parametric-polymorphism, predicates, trie
• Language: Haskell
• Homepage:
• Size: 1.6 MB
• Stars: 5
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
pred-trie

=========

A predicative trie library - use predicates instead of literal match to capture

classes of results, instead of enumerating distinguished ones.

## Usage

The predicates are existentially quantified such that a predicate _creates_ an

unknown type, while it's result must have the _necessary arity_, matching the

quantified type, to fulfill the lookup:

```haskell

PredTrie s a

  = PNil

  | forall t. PCons

      { predicate :: s -> Maybe t

      , result    :: t -> a

      }

```

...basically.

I broke the lookup phases into "steps", like the [tries](https://github.com/athanclark/tries)

package, and used the fastest-lookup `HashMapStep` trie implementation for the

literal lookups. For more info, read the code :D

## How to run tests

```bash

stack test

```

## Benchmarking

```bash

stack bench --benchmark-arguments="--output profile.html"

```