A presentation at React Day Berlin in in Berlin, Germany by Robin Pokorny
import * as t from ‘io-ts’; const Email = t.brand( t.string, (s): s is t.Branded<string, EmailBrand> => isEmail(s), ‘Email’, ); type Email = t.TypeOf<typeof Email>;
Email.decode(”) Email.decode(‘r0b1n’) Email.decode(‘r@0b1n.at’) Email.decode(2020) Email.decode(null)
import * as E from ‘fp-ts/lib/Either’ pipe( Email.decode(anything), E.fold(onFail, onSuccess) )
const a: Email = ‘r@0b1n.at’ // -> Type ‘“r@0b1n.at”’ is not assignable to type ‘Branded<string, Email>’.
const SignUpForm = t.type({ company: String50, email: Email, password: Password, phone: option(Phone), sendNewsletter: t.boolean, }); const form = useForm( SignUpForm, initialState );
https://typescript.fun @estejs
TypeScript is the main dialect developers use for writing React applications. React has a functional nature, however, TypeScript has not. It lacks some popular patterns and data structures we use and love in other functional languages like ReasonML, Elm, or PureScript. Fortunately, for the rescue, there is a rising library called fp-ts. Let me show you how it can help you.
The following resources were mentioned during the presentation or are useful additional information.
for free. You
can too.