I wrote a Babel plugin which brings a similar syntax to JavaScript, so you can write this: for (let i = 0; i < someVar; i++) { invariant: i < 10000;

I wrote a Babel plugin which brings a similar syntax to JavaScript, so you can write this: for (let i = 0; i < someVar; i++) { invariant: i < 10000; console.log(i); } along with other kinds of contract, like preconditions and postconditions - https://github.com/codemix/babel-plugin-contracts https://github.com/codemix/babel-plugin-contracts