tab completion for a LISP-like interpreter

[kovzol]

Hi, I am about to create a web version for a LISP-like interpreter. What I really need is tab completion. That is, something like completing the input in a form like "(command ...)". Here the command begins with a parenthesis. Does jquery.terminal offer a way to do that with minimal effort?

[jcubic]

You can look at how I've created completion for LIPS Scheme. Not sure if you saw it. You can find the code for the terminal on that website here:

https://github.com/jcubic/lips/blob/master/lib/js/terminal.js#L200-L220

            completion: function(string) {
                let tokens = lips.tokenize(this.before_cursor(), true);
                tokens = tokens.map(token => token.token);
                // Array.from is need to for jQuery terminal version <2.5.0
                // when terminal is outside iframe and lips is inside
                // jQuery Terminal was using instanceof that don't work between iframes
                var env = Array.from(interpreter.get('env')().to_array());
                if (!tokens.length) {
                    return env;
                }
                const last = tokens.pop();
                if (last.trim().length) {
                    const globals = Object.getOwnPropertyNames(window);
                    const prefix = tokens.join('');
                    const re = new RegExp('^' + $.terminal.escape_regex(last));
                    var commands = env.concat(globals).filter(name => {
                        return re.test(name);
                    }).map(name => prefix + name);
                    return Array.from(commands);
                }
            },

The code uses my lisp parser to parse the whole code and get the last word that can be completed.

[kovzol]

Thank you!

[jcubic]

What's cool about my terminal is that it also has parentheses matching and scheme syntax highlighting. Similar code (but older) is on the BiwaScheme website.

[kovzol]

Thank you!