Unlambda

<p>Unlambda is a minimal, "nearly <a href="/facts/Purely_functional_language/am3DcNAd">pure</a>" <a href="/facts/Functional_programming_language/cdxqPEIM">functional programming language</a> invented by David Madore. It is based on <a href="/facts/Combinatory_logic/D7NNo4xT">combinatory logic</a>, an expression system without the <a href="/facts/Lambda_calculus/DaD3RuQ4">lambda operator</a> or free variables. It relies mainly on two built-in functions (s and k) and an apply operator (written `, the <a href="/facts/Backquote/pVo48UeD">backquote</a> character). These alone make it <a href="/facts/Turing-complete/73goop44">Turing-complete</a>, but there are also some <a href="/facts/Input%2foutput/WQTE8Jas">input/output</a> (I/O) functions to enable interacting with the user, some shortcut functions, and a <a href="/facts/Lazy_evaluation/mD3DxDkc">lazy evaluation</a> function. Variables are unsupported.
</p><p>Unlambda is <a href="/facts/Free_and_open-source_software/1cHtjLCB">free and open-source software</a> distributed under a <a href="/facts/GNU_General_Public_License/S75KhLSX">GNU General Public License</a> (GPL) 2.0 or later.
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Unlambda open-in-new

Unlambda