Squine stands for “scheme quine”. It’s a little IDE for the subset of scheme introduced in The Little Schemer. It’s based on Yon, and bundles your scheme code, the IDE as well as a little scheme interpreter within a single HTML file that you can pass around. As of now, the only primitives included are: define quote car cdr cons null? zero? atom? number? eq? or and add1 sub1 lambda cond letrec. More might get added in the future!

When you say “language,” most programmers think of the big ones, like FORTRAN or COBOL or Pascal. In fact, a language is any mechanism to express in- tent, and the input to many programs can be viewed profitably as statements in a language. This column is about those “little languages.”