Yes. I've enjoyed playing around with gambit, but the module system is a huge headache, and the documentation is quite sparse. R7RS, I hope, will at least give a better baseline for a newcomer like myself. (For the curious, C integration and speed are necessary for the project. Gambit is great for this.)
I am looking for a Scheme to implement inside an iOS app. I was looking into TinyScheme and Gambit, but was leaning towards TinyScheme due to its size.
Chibi is about the same size, and unlike TinyScheme is a real Scheme with hygienic macros and a fast VM (TinyScheme is hopelessly slow). It also has features like Huffman compressed immediate symbols to further reduce runtime heap usage - the raw image size isn't the whole story.
It depends on what you mean by real world applications, but Chibi has many features including threads, networking and an FFI suitable for any application. R7RS large will have even more libraries. It will be complete when it's completed, but many of the individual libraries will be usable before then.
Thanks for answer, I want to make a simple game in scheme, so I am considering chibi, maybe I need to try somehow to add opengl binding. I know there is other implementations but I want to try chibi (r7rs) :)
Apart from Racket, Chicken Scheme is the most active Scheme and it has a lot of libraries (eggs as they call it) from OS interface to amazon web services and web frameworks.
How large does the heap need to be for the garbage collector to work effectively? Could this theoretically run on something like the TI Stellaris LaunchPad, which is an ARM chip with 256KB of Flash and 32KB of RAM?
The default heap is 2MB, but will run with 756KB. If you want to skip the init.scm file (-q command-line option) it will run with just 10KB providing only definitions and C primitives, but I haven't tested this extensively - I had no idea they still made devices with such little memory :)
Note: I don't have access to the original manual link either, so I can't confirm that it's exactly the same document. It describes the language in details.
That's incorrect. You can embed an interpreter and interpreted code in an iOS app and many do. You just can't download new interpreted code after the application has been installed. You can't download new binary code, either.