https://azukipan.com/_next/static/chunks/479.3f769b654ba2e671.js

1"use strict";(self.webpackChunk_N_E=self.webpackChunk_N_E||[]).push([[479],{60479:function(n,s,e){e.r(s);var a=e(85893),c=e(11151);function l(n){let s=Object.assign({p:"p",code:"code",pre:"pre",span:"span",img:"img"},(0,c.ah)(),n.components);return(0,a.jsxs)(a.Fragment,{children:[(0,a.jsxs)(s.p,{children:["パラメータには、",(0,a.jsx)(s.code,{children:"name"}),"、",(0,a.jsx)(s.code,{children:"age"}),"、",(0,a.jsx)(s.code,{children:"phoneNumber"}),"、",(0,a.jsx)(s.code,{children:"address"}),"がある、",(0,a.jsx)(s.code,{children:"Profile"}),"という関数があったとします。"]}),"\n",(0,a.jsx)(s.pre,{className:"language-ts",children:(0,a.jsxs)(s.code,{className:"language-ts",children:[(0,a.jsx)(s.span,{className:"token keyword",children:"type"})," ",(0,a.jsx)(s.span,{className:"token class-name",children:(0,a.jsx)(s.span,{className:"token maybe-class-name",children:"Profile"})})," ",(0,a.jsx)(s.span,{className:"token operator",children:"="})," ",(0,a.jsx)(s.span,{className:"token punctuation",children:"{"}),"\n  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1™ã€‚"}),"\n",(0,a.jsx)(s.p,{children:"では、割り当てても割り当てなくてもどちらでもよい場合は、どうすればいいでしょうか。"}),"\n",(0,a.jsx)(s.p,{children:"その場合は、オプションにしたい型の後に『?』を入力します。"}),"\n",(0,a.jsx)(s.pre,{className:"language-ts",children:(0,a.jsxs)(s.code,{className:"language-ts",children:[(0,a.jsx)(s.span,{className:"token keyword",children:"type"})," ",(0,a.jsx)(s.span,{className:"token class-name",children:(0,a.jsx)(s.span,{className:"token maybe-class-name",children:"Profile"})})," ",(0,a.jsx)(s.span,{className:"token operator",children:"="})," ",(0,a.jsx)(s.span,{className:"token punctuation",children:"{"}),"\n  name",(0,a.jsx)(s.span,{className:"token operator",children:":"})," ",(0,a.jsx)(s.span,{className:"token builtin",children:"string"}),(0,a.jsx)(s.span,{className:"token punctuation",children:";"}),"\n  age",(0,a.jsx)(s.span,{className:"token operator",children:":"})," ",(0,a.jsx)(s.span,{className:"token builtin",children:"number"})," ",(0,a.jsx)(s.span,{className:"token operator",children:"|"})," ",(0,a.jsx)(s.span,{className:"token builtin",children:"string"}),(0,a.jsx)(s.span,{className:"token punctuation",children:";"}),"\n  phoneNumber",(0,a.jsx)(s.span,{className:"token operator",children:":"})," ",(0,a.jsx)(s.span,{className:"token builtin",children:"string"}),(0,a.jsx)(s.span,{className:"token punctuation",children:";"}),"\n  address",(0,a.jsx)(s.span,{className:"token operator",children:"?"}),(0,a.jsx)(s.span,{className:"token operator",children:":"})," ",(0,a.jsx)(s.span,{className:"token builtin",children:"string"}),(0,a.jsx)(s.span,{className:"token punctuation",children:";"}),"\n",(0,a.jsx)(s.span,{className:"token punctuation",children:"}"}),(0,a.jsx)(s.span,{className:"token punctuation",children:";"}),"\n"]})}),"\n",(0,a.jsx)(s.p,{children:"すると、"}),"\n",(0,a.jsx)(s.p,{children:(0,a.jsx)(s.img,{src:"/images/78-image4.png",alt:"image4"})}),"\n",(0,a.jsxs)(s.p,{children:[(0,a.jsx)(s.code,{children:"newUser"}),"のエラーが消えました。"]}),"\n",(0,a.jsx)(s.p,{children:"パラメータをオプションにしたい場合は、『?』を付けて指定してください。"})]})}s.default=function(){let n=arguments.length>0&&void 0!==arguments[0]?arguments[0]:{},{wrapper:s}=Object.assign({},(0,c.ah)(),n.components);return s?(0,a.jsx)(s,Object.assign({},n,{children:(0,a.jsx)(l,n)})):l(n)}}}]);