The gulcii package

[Tags: gpl, program]

GULCII is an untyped lambda calculus interpreter supporting interactive modification of a running program with graphical display of graph reduction.

There are three variants of lambda abstraction: lazy, strict, and copy:

> x . f x x -- x is evaluated lazily with sharing > x ! f x x -- x is evaluated strictly and shared > x ? f x x -- x is copied before any evaluation

There is additional syntax sugar for natural numbers and lists, using

> [0,1,2,3]

There is a small standard library based loosely around the Haskell Prelude, with additions geared towards MIDI generation for live-coding music, implemented using a mechanism similar to Debug.Trace.trace:

> x y . { print : x } y

Quick start:


If you have Pure-data and Timidity, try:

 timidity -iA -Oj &
 pd -alsamidi ~/.cabal/share/gulcii- &
 gulcii | pdsend 8765

See also: live-sequencer which has many more features (but no sharing during evaluation).


Dependenciesbase (>=3 && <6), cairo (>=0.11 && <0.13), containers (>=0.3 && <0.6), filepath (>=1.1 && <1.4), gtk (>=0.11 && <0.13)
AuthorClaude Heiland-Allen
CategorySound, Music, GUI
Home page
Source repositoryhead: git clone git://
this: git clone git://
UploadedSat May 18 20:42:54 UTC 2013 by ClaudeHeilandAllen
Downloads174 total (14 in last 30 days)
StatusDocs not available [build log]
Successful builds reported [all 2 reports]


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