Embedding Lisp in C++ – A Recipe

http://chriskohlhepp.wordpress.com/embedding-lisp-in-cplusplus-a-recipe/

by ingve • 12 years ago

64 10 12 years ago

chriskohlhepp.wordpress.com

CurtHagenlocher• 12 years ago

Lisp is everywhere because compilers use ASTs?

progman2• 12 years ago

Probably because more people realize how powerful Lisp actually is.

AnimalMuppet2• 12 years ago

Lisp uses ASTs. Not all uses of ASTs are Lisp, though. And no matter how many people realize how powerful Lisp is, all ASTs still won't be Lisps.

People realizing that Lisp is powerful does not fix the underlying logical fallacy.

AnimalMuppet2• 12 years ago

Yeah, that bugged me, too.

Lisp code is written as an AST? True. C++ (and other) compilers convert code to an AST? Also true. Therefore "No matter if you are programming in Python or C++, Lisp is invariably what holds up the scaffolding behind the scenes. This is true because Lisp is the Lingua Franca of your compiler"? Non sequitur (literally, "it does not follow").

That logic boils down to "A is a C, and B is a C, therefore A is a B". No, it isn't. It would be equally (il)logical to claim that "B is an A", that is, that Lisp was a C++ compiler.

greyfade• 12 years ago

In my reading, it appears to be an assumption based on GCC, which apparently uses lisp-like code to represent its AST. (Is this true? I don't know, I haven't looked.)

jobu• 12 years ago

Some references or more examples of compilers that use Lisp would be helpful. It was my understanding that compilers used tools based on LEX & YACC (Flex & Bison for GCC). The author mentions Clang, but Google couldn't find anything definitive that says Clang uses Lisp internally.

http://dinosaur.compilertools.net/

http://www.tldp.org/HOWTO/GCC-Frontend-HOWTO-3.html

thegeomaster• 12 years ago

It only has to do with the internal usage of ASTs (abstract syntax trees) within compilers. Lisp code can be likened to an abstract syntax tree, and GCC just uses the familiar Lisp indenting rules and parenthesis syntax to output its ASTs. Therefore, I don't think compilers really use Lisp internally, it's just that they boil the code down to a form that resembles Lisp and can be conveniently output as so.

agentultra• 12 years ago

This is amazing! Thanks for the tip. I'm trying this out on my next game. CL is much more powerful than Lua and something I'm more comfortable with as a language. Seems to be nearly as painless integrating too.

lisper• 12 years ago

A Lisp embedded in C++

https://github.com/rongarret/ciel

It's a toy, but it works.

Embedding Lisp in C++ – A Recipe

Related Stories