akihisa-shimada

import { Helmet, HelmetProvider } from "react-helmet-async";

const faqSchema = {
  "@context": "https://schema.org",
  "@type": "FAQPage",
  mainEntity: [
    {
      "@type": "Question",
      name: "よくある質問",
      acceptedAnswer: {

akihisa-shimada

function identity<T>(arg: T): T {
  return arg;
}

console.log(identity<string>("string"));
console.log(identity(1));

akihisa-shimada

interface Lengthwise {
  length: number;
}

function loggingIdentity<T>(arg: T): T {
  console.log(arg.length);
  // -> Property 'length' does not exist on type 'T'.(2339)
  return arg;
}

akihisa-shimada

const fetcher = async(url: string): Promise<any> => {
    const res = await fetch(url).then(res => res.json());
    return res;
}

export const getUser = async(): Promise<any>  => {
    const user = await fetcher('https://example.com/api/user');
    return user;
}

akihisa-shimada

const fetcher = async<T>(url: string): Promise<T> => {
    const res = await fetch(url).then<T>(res => res.json());
    return res;
}

export const getUser = async(): Promise<{id: number, name: string}> => {
    const user = await fetcher<{id: number, name: string}>('https://example.com/api/user');
    return user;
}

akihisa-shimada

const functionA = <T, U>(bool: boolean, param1: T, param2: U): T | U => {
  if (bool) return param1;
  return param2;
}

const result1 = functionA(true, 1, '文字列');
const result2 = functionA(false, 1, '文字列');

console.log(result1) // 1
console.log(result2) // 文字列

akihisa-shimada

interface ExampleInterface<T, U> {
  value1: T;
  value2: U;
}

const obj: ExampleInterface<string, number> = { value1: '文字列', value2: 1 };
console.log(obj.value1); // 文字列
console.log(obj.value2); // 1

akihisa-shimada

interface Lengthwise {
  length: number;
}

function loggingIdentity<T extends Lengthwise>(arg: T): T {
  console.log(arg.length);
  return arg;
}

loggingIdentity(['hello world'])

akihisa-shimada

package com.example.proto.grpc.exception.message;

import com.google.protobuf.Message;
import com.google.rpc.LocalizedMessage;

/**
 * エラーメッセージの詳細を扱います
 */
public interface DetailMessage {

akihisa-shimada

package com.example.proto.grpc.exception.message;

import io.grpc.Status;

/**
 * 特定のgRPCレスポンスのための例外クラスです。
 *
 * @see org.springframework.web.server.ResponseStatusException
 */
public class ResponseStatusException extends RuntimeException {