Embeddable scripting language used frequently in games combining simple procedural syntax with powerful data description constructs based on associative arrays and extensible semantics.
A complete game framework, editor and toolset for the creation of PC multiplayer action games. It is the result of several years of development effort at spanish developer Tragnarion Studios, and is based in nebula2, the open-source 3D engine from Radon Labs.
Following the Snobol tradition, LPeg defines patterns as first-class objects. That is, patterns are regular Lua values (represented by userdata). The library offers several functions to create and compose patterns. With the use of metamethods, several of these functions are provided as infix or prefix operators. On the one hand, the result is usually much more verbose than the typical encoding of patterns using the so called regular expressions (which typically are not regular expressions in the formal sense). On the other hand, first-class patterns allow much better documentation (as it is easy to comment the code, to use auxiliary variables to break complex definitions, etc.) and are extensible, as we can define new functions to create and compose patterns.