Hacker News

Shirye-shiryen meta-style C++ samfuri

Sharhi

11 min read Via github.com

Mewayz Team

Editorial Team

Hacker News

Wani Nau'in Sihiri Na Haɗa: Lisp-Style C++ Samfura Metaprogramming

A cikin faffadan ci gaban software, C++ ya shahara saboda ƙarfinsa da kuma aiki. Amma duk da haka, an ɓoye shi a cikin hadadden tsarin tattarawa ya ta'allaka ne da yanayin da ke jin kusan baƙo: samfuri metaprogramming (TMP). Lokacin da aka ɗauka zuwa matsananciyar ma'ana, C++ TMP ya fara kama da harshen shirye-shirye mai aiki da kansa, wanda ke aiwatarwa gaba ɗaya a lokacin tattarawa. Daidaituwa da Lisp, ɗaya daga cikin tsofaffin kuma mafi tasiri harsunan shirye-shirye, suna da ban mamaki da zurfi. Wannan hanyar tana ba masu haɓaka damar sauke hadaddun ƙididdigewa da dabaru daga lokacin aiki zuwa tara-lokaci, ƙirƙirar ingantaccen inganci da nau'in lambar aminci. Fahimtar wannan tsarin salon Lisp shine mabuɗin buɗe sabon matakin ƙayyadaddun ƙa'ida, ƙa'idar da muke ƙima sosai a Mewayz lokacin yin gine-gine masu ƙarfi, tsarin kasuwanci na zamani.

Harshen Shirye-shiryen Hatsari A Cikin C++

C++ samfuri an tsara su ne don sauƙaƙan nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in canji, kamar ƙirƙirar 'List' ko 'List'. Koyaya, ma'aunin C++, a cikin neman gama-gari, da gangan ya ƙirƙiri cikakken yaren Turing. Wannan yana nufin cewa bisa ka'ida, duk wani lissafin da shirin zai iya yi shi ma na'urar tattara bayanai na C++ na iya yin ta yayin aiwatar da samfurin nan take. Gano wannan iyawar ya haifar da haihuwar samfuri metaprogramming. An gano cewa ta amfani da ƙwarewar samfuri, maimaitawa, da sigogin samfuri, mutum zai iya rubuta shirye-shiryen da mai tarawa ke aiwatarwa yayin gina aikace-aikacenku. Wannan “harshen” na lokaci-lokaci ba shi da masu canji a ma'anar gargajiya; yanayinsa yana kunshe ne a cikin sigogin samfuri da kansu, kuma tsarin sarrafa shi yana dogara ne akan maimaitawa da harhada sharaɗi.

Ruguwar Aiki, Tunani mai kama da Lisp

Don rubuta metaprograms yadda ya kamata, dole ne mutum ya rungumi tsarin tunani mai aiki, kamar mai shirye-shiryen Lisp. Babu wani yanayi mai canzawa ko madaukai a cikin ma'anar gargajiya. Instead, everything is achieved through recursion and the manipulation of types and compile-time constants. Yi la'akari da misali mai sauƙi: ƙididdige ƙididdiga. A cikin Lisp, zaku iya amfani da aikin maimaitawa. A cikin C++ TMP, tsarin yana kama da kamanceceniya, amma yana aiki tare da iri da ƙima.

  • Bayani mara canzawa: Kamar a cikin Lisp, bayanai a cikin TMP ba su canzawa. Da zarar an saita siginar samfuri, ba za a iya canza shi ba; kawai za ku iya ƙirƙirar sababbin "misali" tare da sigogi daban-daban.
  • Maimaituwa azaman maimaitawa: Tun da babu 'don' ko 'lokacin' madaukai, maimaitawa shine tsarin farko na maimaita ayyuka. Samfurin yana kiran kansa tare da sabunta sigogi har sai an kai ga harka ta tushe (ta hanyar ƙwararrun samfuri).
  • Mai amfani da Nau'ukan, Ba Ƙimar Ƙimar kawai ba:Mafi ƙarfin al'amari na TMP shine ikonsa na ƙididdigewa da nau'i. Kuna iya ƙirƙirar lissafin nau'in, bincika nau'ikan kaddarorin, kuma zaɓi nau'ikan bisa ga sharuɗɗa, kunna dabarun shirye-shiryen gabaɗaya.

Wannan tsarin yana tilasta wata hanyar tunani ta daban, wacce ke ba da fifikon tunani akan matakan da suka dace, wanda ke haifar da mafi ƙarfi da ƙaƙƙarfan lambobi.

"Template metaprogramming shine ainihin harshe mai aiki da aka saka a cikin C++. Yana da kayan aiki mai ƙarfi, amma yana buƙatar tunani game da shirye-shirye ta wata hanya ta daban-hanyar da sau da yawa ya fi m da lissafi." - Memba na kwamitin C++

Ayi amfani da Aiki a Tsarin Modular

Yayin da misali mai mahimmanci na ilimi ne, ainihin ikon Lisp-style TMP yana haskakawa a cikin aikace-aikace masu amfani waɗanda ke amfana daga abubuwan da ba za a iya jurewa ba. Misali, ana iya amfani da shi don samar da ingantattun tsarin bayanai na musamman ga nau'in da aka bayar, don inganta ƙayyadaddun jeri a lokacin tattarawa, ko aiwatar da ƙayyadaddun ƙirar ƙira kamar Tsara-Tsarin Manufofi. A cikin mahallin dandali kamar Mewayz, wanda ke nufin zama OS na kasuwanci na zamani, waɗannan fasahohin suna da kima. Suna ƙyale mu mu gina ainihin abubuwan haɗin gwiwa waɗanda ke da sauƙin sassauƙa da ƙwarewa na musamman. Ana iya ƙirƙira API ɗin module ta amfani da TMP don tilasta ƙa'idodin kasuwanci da alaƙar bayanai a matakin nau'in, kama yuwuwar ɓata lokaci tun kafin a tura software ɗin. Wannan aminci na lokaci-lokaci yana da mahimmanci don gina ingantattun tsare-tsare masu daidaitawa waɗanda kasuwancin ke dogaro da su.

Juyin Halitta da Gaba tare da `constexpr`

Ana yawan sukar farkon C++ TMP saboda kalmomin sirri da lokutan tattarawa. Gane wannan, kwamitin ma'auni na C++ tun daga lokacin ya ƙaddamar da ƙarin fasalulluka na abokantaka na masu haɓakawa, musamman 'constexpr' da, kwanan nan, 'consteval'. Waɗannan fasalulluka suna ba da damar ƙididdigewa da yawa waɗanda sau ɗaya suna buƙatar hadaddun dabarun samfuri don rubuta su ta amfani da saba, maƙasudin C++ mai mahimmanci wanda ke aiwatarwa a lokacin tattarawa. Koyaya, tsarin TMP-style na Lisp ya kasance mai dacewa don ƙididdige nau'ikan nau'ikan ƙididdiga da al'amuran da ke buƙatar mafi mahimmancin iko akan tsarin nan take. Mai haɓaka C++ na zamani yanzu yana da nau'ikan kayan aiki, daga TMP na al'ada zuwa ayyukan 'constexpr', yana basu damar zaɓar kayan aikin da ya dace don aikin kuma su rubuta mai tsafta, ƙarin tsari na metaprograms.

💡 DID YOU KNOW?

Mewayz replaces 8+ business tools in one platform

CRM · Invoicing · HR · Projects · Booking · eCommerce · POS · Analytics. Free forever plan available.

Start Free →

Tambayoyin da ake yawan yi

Mai Daban-daban na Mai Haɗa Sihiri: Lisp-Style C++ Template Metaprogramming

A cikin faffadan ci gaban software, C++ ya shahara saboda ƙarfinsa da kuma aiki. Amma duk da haka, an ɓoye shi a cikin hadadden tsarin tattarawa ya ta'allaka ne da yanayin da ke jin kusan baƙo: samfuri metaprogramming (TMP). Lokacin da aka ɗauka zuwa matsananciyar ma'ana, C++ TMP ya fara kama da harshen shirye-shirye mai aiki da kansa, wanda ke aiwatarwa gaba ɗaya a lokacin tattarawa. Daidaituwa da Lisp, ɗaya daga cikin tsofaffin kuma mafi tasiri harsunan shirye-shirye, suna da ban mamaki da zurfi. Wannan hanyar tana ba masu haɓaka damar sauke hadaddun ƙididdigewa da dabaru daga lokacin aiki zuwa tara-lokaci, ƙirƙirar ingantaccen inganci da nau'in lambar aminci. Fahimtar wannan tsarin salon Lisp shine mabuɗin buɗe sabon matakin ƙayyadaddun ƙa'ida, ƙa'idar da muke ƙima sosai a Mewayz lokacin yin gine-gine masu ƙarfi, tsarin kasuwanci na zamani.

Harshen Shirye-shiryen Hatsari A Cikin C++

C++ samfuri an tsara su ne don sauƙaƙa nau'in, kamar ƙirƙirar 'List' ko 'List'. Koyaya, ma'aunin C++, a cikin neman gama-gari, da gangan ya ƙirƙiri cikakken yaren Turing. Wannan yana nufin cewa bisa ka'ida, duk wani lissafin da shirin zai iya yi shi ma na'urar tattara bayanai na C++ na iya yin ta yayin aiwatar da samfurin nan take. Gano wannan iyawar ya haifar da haihuwar samfuri metaprogramming. An gano cewa ta amfani da ƙwarewar samfuri, maimaitawa, da sigogin samfuri, mutum zai iya rubuta shirye-shiryen da mai tarawa ke aiwatarwa yayin gina aikace-aikacenku. Wannan “harshen” na lokaci-lokaci ba shi da masu canji a ma'anar gargajiya; yanayinsa yana kunshe ne a cikin sigogin samfuri da kansu, kuma tsarin sarrafa shi yana dogara ne akan maimaitawa da harhada sharaɗi.

Ruguwar Aiki, Tunani mai kama da Lisp

Don rubuta metaprograms yadda ya kamata, dole ne mutum ya rungumi tsarin tunani mai aiki, kamar mai shirye-shiryen Lisp. Babu wani yanayi mai canzawa ko madaukai a cikin ma'anar gargajiya. Instead, everything is achieved through recursion and the manipulation of types and compile-time constants. Yi la'akari da misali mai sauƙi: ƙididdige ƙididdiga. A cikin Lisp, zaku iya amfani da aikin maimaitawa. A cikin C++ TMP, tsarin yana kama da kamanceceniya, amma yana aiki tare da iri da ƙima.

Ayi amfani da Aiki a Tsarin Modular

Yayin da misali mai mahimmanci na ilimi ne, ainihin ikon Lisp-style TMP yana haskakawa a cikin aikace-aikace masu amfani waɗanda ke amfana daga abubuwan da ba za a iya jurewa ba. Misali, ana iya amfani da shi don samar da ingantattun tsarin bayanai na musamman ga nau'in da aka bayar, don inganta ƙayyadaddun jeri a lokacin tattarawa, ko aiwatar da ƙayyadaddun ƙirar ƙira kamar Tsara-Tsarin Manufofi. A cikin mahallin dandali kamar Mewayz, wanda ke nufin zama OS na kasuwanci na zamani, waɗannan fasahohin suna da kima. Suna ƙyale mu mu gina ainihin abubuwan haɗin gwiwa waɗanda ke da sauƙin sassauƙa da ƙwarewa na musamman. Ana iya ƙirƙira API ɗin module ta amfani da TMP don tilasta ƙa'idodin kasuwanci da alaƙar bayanai a matakin nau'in, kama yuwuwar ɓata lokaci tun kafin a tura software ɗin. Wannan aminci na lokaci-lokaci yana da mahimmanci don gina ingantattun tsare-tsare masu daidaitawa waɗanda kasuwancin ke dogaro da su.

Juyin Halitta da Gaba tare da `constexpr`

Ana yawan sukar farkon C++ TMP saboda kalmomin sirri da lokutan tattarawa. Gane wannan, kwamitin ma'auni na C++ tun daga lokacin ya ƙaddamar da ƙarin fasalulluka na abokantaka na masu haɓakawa, musamman 'constexpr' da, kwanan nan, 'consteval'. Waɗannan fasalulluka suna ba da damar ƙididdigewa da yawa waɗanda sau ɗaya suna buƙatar hadaddun dabarun samfuri don rubuta su ta amfani da saba, maƙasudin C++ mai mahimmanci wanda ke aiwatarwa a lokacin tattarawa. Koyaya, tsarin TMP-style na Lisp ya kasance mai dacewa don ƙididdige nau'ikan nau'ikan ƙididdiga da al'amuran da ke buƙatar mafi mahimmancin iko akan tsarin nan take. Mai haɓaka C++ na zamani yanzu yana da nau'ikan kayan aiki, daga TMP na al'ada zuwa ayyukan 'constexpr', yana basu damar zaɓar kayan aikin da ya dace don aikin kuma su rubuta mai tsafta, ƙarin tsari na metaprograms.

Shin Kun Shirya Sauƙaƙe Ayyukanku?

Ko kuna buƙatar CRM, daftari, HR, ko duk nau'ikan 208 - Mewayz ya rufe ku. Kasuwanci 138K+ sun riga sun canza.

An Fara Kyauta →

Start managing your business smarter today

Join 30,000+ businesses. Free forever plan · No credit card required.

Ready to put this into practice?

Join 30,000+ businesses using Mewayz. Free forever plan — no credit card required.

Start Free Trial →

Ready to take action?

Start your free Mewayz trial today

All-in-one business platform. No credit card required.

Start Free →

14-day free trial · No credit card · Cancel anytime