Syntax extensions are a feature in LIPS Scheme that allow users to add new syntax. They work similar to readers, macro in Common Lisp. You create a sequence of characters that maps to a function that is executed by the parser, the function works similar to a macro and a result of the function is returned by the parser in place of the sequence of defined characters.

The first version of LIPS Scheme had regex based tokenizer. It was using a single regex to split the input string into tokens. In this article, I will show the internals of the new Lexer in LIPS Scheme.

LIPS Scheme support regular expression literals, but it's not the only one implementation that support those. Other implementation includes Gauche and Kawa.

Unfortunetlly, you can't easily use those regular expressions in GNU Emacs, my main editor of choice.

This is the first article on LIPS blog. In this article I will write about the history of LIPS Scheme interpreter.