Better Flow Error Messages for the JavaScript Ecosystem

:::info[Historical] This post announced improved error messages when it was introduced. For current syntax and behavior, see the Error Messages documentation. :::

Over the last year, the Flow team has been slowly auditing and improving all the possible error messages generated by the type checker. In Flow 0.66 we’re excited to announce a new error message format designed to decrease the time it takes you to read and fix each bug Flow finds.