Installation

npm install @barandis/kessel

This won't actually be available on NPM until I finish basic documentation, which should happen around the beginning of December.

There are also self-contained files (kessel.js and the minified kessel.min.js) in the lib directory of the distribution. These will work in the browser (where a global kessel object is provided) or with CommonJS or AMD.

Assertions

The default Kessel library uses assertions to ensure that input to parsers is what it's supposed to be. This is more than type-checking like in TypeScript - runtime failures will result if the wrong kind of input is given to a parser. Defensive programming is not normally a philosophy that I take to, but understanding the source of errors is so important in parsing that it seems appropriate here.

The assertions slow down parsing, though I suspect that the amount of time added is negligible (this has not yet been benchmarked, though that is on the list of things to do). Every input that has a definitive type is checked, so if you have a alt that takes a thousand parsers, maybe that will be a bit slower.

The distribution does contain versions without assertions, named kessel.noassert.js and kessel.noassert.min.js. If you are seriously concerned about performance you can choose to use these instead.