t3dotgg

// Types for the result object with discriminated union
type Success<T> = {
  data: T;
  error: null;
};

type Failure<E> = {
  data: null;
  error: E;
};

JacobWeisenburger

type ValidateType<T extends string> =
    T extends 'bad' ? 'Error message'
    : T extends 'another bad' ? 'Another error message'
    : T extends 'Error message' | 'Another error message' ? `Can't use '${ T }'`
    : T

function fn<T extends string> ( arg: ValidateType<T> ) { }

fn( 'this should work' ) // works
fn( 'bad' ) // Argument of type '"bad"' is not assignable to parameter of type '"Error message"'.

JacobWeisenburger

/**
CORS blocks this request from the browser, so you will need to run this code on the server.
*/
async function checkIfYouTubeChannelIsLive ( channelId: string ) {
    const liveCheckURL = `https://www.youtube.com/embed/live_stream?channel=${ channelId }`
    const responseText = await fetch( liveCheckURL ).then( res => res.text() )
    const isLive = responseText.indexOf( 'This video is unavailable' ) < 0
    return isLive
}

JacobWeisenburger

import { z } from 'zod'

type ErrorCode = z.ZodIssueCode | 'required'
type Message = string
type MessageBuilder = ( data: unknown, options?: any[] ) => Message
type ErrorRecord = Partial<Record<ErrorCode, Message | MessageBuilder>>
function makeErrorMap ( errorRecord: ErrorRecord ): z.ZodErrorMap {
    return ( issue, ctx ) => {
        const options = issue.code === 'invalid_enum_value'
            ? issue.options : undefined

JacobWeisenburger

import { z } from 'zod'

function safeParseJSON ( string: string ): any {
    try { return JSON.parse( string ) }
    catch { return string }
}

function searchParamsToValues ( searchParams: URLSearchParams ): Record<string, any> {
    return Array.from( searchParams.keys() ).reduce( ( record, key ) => {
        const values = searchParams.getAll( key ).map( safeParseJSON )

souporserious

const headings = content
  .split('\n')
  .filter((line) => line.match(/#{1,3}\s/))
  .map((line) => {
    const [, level, title] = line.match(/(#{1,3})\s(.*)/)
    return {
      level: level.length,
      title,
    }
  })

pierrejoubert73

How to add a collapsible section in markdown

1. Example

Click me

Heading

1. Foo
2. Bar
   • Baz

• Qux