https://github.com/billiegoose/lambda-calculator

A small parser for the λ-calculus written in Haskell that I'm making for fun.
https://github.com/billiegoose/lambda-calculator

Last synced: 24 days ago
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A small parser for the λ-calculus written in Haskell that I'm making for fun.

• Host: GitHub
• URL: https://github.com/billiegoose/lambda-calculator
• Owner: billiegoose
• License: mit
• Created: 2014-05-11T04:15:09.000Z (over 10 years ago)
• Default Branch: master
• Last Pushed: 2014-05-13T06:10:05.000Z (over 10 years ago)
• Last Synced: 2024-10-06T03:23:46.082Z (3 months ago)
• Language: Haskell
• Size: 145 KB
• Stars: 1
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
lambda-calculator

=================

A small parser for the λ-calculus written in Haskell that I'm making for fun.

> "You made _what?_" See http://en.wikipedia.org/wiki/Lambda_calculus

Usage

-----

Load the program in ghci.

Type `cal "some lambda expression"` to see the output of small step reduction.

Example:

```Haskell

*Main> cal "(/x./y.y x) y /z.z"

(((/x.(/y.(y x))) y) (/z.z))

((/_y.(_y y)) (/z.z))

((/z.z) y)

y

```

Syntax

------

Variables: any word using only lowercase, uppercase, or numbers.

Abstraction: λ_var_._term_ is written as `/var.term` 

Application: a single space, e.g. `(/id.id) 1` == `1`

Grouping: done using parentheses, e.g. `(/x.x) x 1` == `(x 1)` but `(/x.x x) 1` == `(1 1)`