| import * as Reader from 'fp-ts/lib/Reader'; | |
| import { RouteData } from 'helpers/routes/types'; | |
| import { pipe, pipeWith } from 'pipe-ts'; | |
| // This will soon be part of fp-ts core | |
| // https://github.com/gcanti/fp-ts/issues/904#issuecomment-619346296 | |
| const chainW: <Q, A, B>( | |
| f: (a: A) => Reader.Reader<Q, B>, | |
| ) => <R>(ma: Reader.Reader<R, A>) => Reader.Reader<R & Q, B> = Reader.chain as Unrestricted; | |
| { | |
| const renderCopyright = RouteData.match({ | |
| Search: () => 'unsplash search copyright goes here', | |
| default: () => 'unsplash copyright goes here', | |
| }); | |
| // ✅ doesn't care about child deps (routeData) | |
| const renderFooter = (year: number) => | |
| pipe(renderCopyright, copyright => `<footer>${copyright} ${year}</footer>`); | |
| // ❌ does care about child deps (year) | |
| const renderPage = (hideFooter: boolean) => ({ year }: { year: number }) => { | |
| if (hideFooter) { | |
| return () => '<body>No Footer.</body>'; | |
| } else { | |
| return pipe(renderFooter(year), footer => `<body>${footer}</body>`); | |
| } | |
| }; | |
| // ❌ does care about child deps (year and routeData) | |
| // ❌ has to manually aggregate child deps | |
| const wrapWithHtml = ({ year, routeData }: { year: number; routeData: RouteData }) => | |
| pipeWith(renderPage(true)({ year })(routeData), page => `<html>${page}</html>`); | |
| declare const routeData: RouteData; | |
| wrapWithHtml({ year: 2014, routeData }); | |
| } | |
| { | |
| const renderCopyright = ({ routeData }: { routeData: RouteData }) => | |
| RouteData.match(routeData, { | |
| Search: () => 'unsplash search copyright goes here', | |
| default: () => 'unsplash copyright goes here', | |
| }); | |
| // ✅ doesn't care about child deps (routeData) | |
| const renderFooter = pipeWith( | |
| renderCopyright, | |
| chainW(copyright => ({ year }: { year: number }) => `<footer>${copyright} ${year}</footer>`), | |
| ); | |
| // ✅ doesn't care about child deps (year and routeData) | |
| const renderPage = (hideFooter: boolean) => { | |
| if (hideFooter) { | |
| return Reader.of('<body>No Footer.</body>'); | |
| } else { | |
| return pipeWith( | |
| renderFooter, | |
| Reader.map(footer => `<body>${footer}</body>`), | |
| ); | |
| } | |
| }; | |
| // ✅ doesn't care about child deps (year and routeData) | |
| const wrapWithHtml = pipeWith( | |
| renderPage(true), | |
| Reader.map(page => `<html>${page}</html>`), | |
| ); | |
| declare const routeData: RouteData; | |
| wrapWithHtml({ year: 2014, routeData }); | |
| } |
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