tiny-invariant

An invariant function takes a value, and if the value is falsy then the invariant function will throw. If the value is truthy, then the function will not throw.

falsy 时 throw 错误，终止程序。（与tiny-warning不同的是后者不会终止程序，只会提示）

Example

import invariant from 'tiny-invariant';
 
invariant(truthyValue, 'This should not throw!');
 
invariant(falsyValue, 'This will throw!');
// Error('Invariant violation: This will throw!');

Dropping your message for kb savings!

Big idea: you will want your compiler to convert this code:

invariant(condition, 'My cool message that takes up a lot of kbs');

Into this:

if (!condition) {
  if ('production' !== process.env.NODE_ENV) {
    invariant(false, 'My cool message that takes up a lot of kbs');
  } else {
    invariant(false);
  }
}

• Babel: recommend babel-plugin-dev-expression
• TypeScript: recommend tsdx (or you can run babel-plugin-dev-expression after TypeScript compiling)

参考

tiny-invariant (opens new window)