1. PHPã®æŠèŠ
PHPã¯ããŠã§ãéçºã®äžçã§éåžžã«äººæ°ã®ããããã°ã©ãã³ã°èšèªãšããŠç¥ãããŠããŸãããããããã®èµ·æºãèæ¯ãäž»ãªçšéãç¹åŸŽããããŠãµãŒããŒãµã€ãã¹ã¯ãªãããšããŠã®åœ¹å²ã«ã€ããŠè©³ããç¥ãããšã§ãPHPã®çã®åãç解ããããšãã§ããŸãã
1.1. PHPã®èµ·æºãšèæ¯
PHPã¯ã1995幎ã«Rasmus Lerdorfã«ãã£ãŠæåã«äœæãããŸãããåœåã¯ãPersonal Home Page ToolsããšããŠç¥ãããŠãããã®èšèªã¯ããŠã§ãããŒãžã®åçãªèŠçŽ ãç°¡åã«äœæããããã®ãã®ã§ãããããããæéãšãšãã«ãPHPã¯ãPHP: Hypertext Preprocessorããšããååž°çãªé åèªãšããŠç¥ãããããã«ãªãããã®æ©èœãšèœåã¯å€§å¹ ã«æ¡åŒµãããŸãããä»æ¥ã§ã¯ãPHPã¯ãŠã§ããµã€ãããªã³ã©ã€ã³ã¢ããªã±ãŒã·ã§ã³ã®ããã¯ãšã³ãéçºã«åºã䜿çšãããŠããŸãã
1.2. PHPã®äž»ãªçšéãšç¹åŸŽ
PHPã®äž»ãªé åã®äžã€ã¯ããµãŒããŒãµã€ãã®ã¹ã¯ãªããèšèªãšããŠã®èœåã§ããããã«ããããŠã§ãããŒãžã«åçãªèŠçŽ ãæ©èœãè¿œå ããããšãã§ããŸããäŸãã°ããŠãŒã¶ãŒããã©ãŒã ã«å ¥åããæ å ±ãåéããããããŒã¿ããŒã¹ããæ å ±ãååŸããŠãŠã§ãããŒãžã«è¡šç€ºãããããããšãã§ããŸãããŸããPHPã¯ãªãŒãã³ãœãŒã¹ã§ãããå€ãã®ãã¹ãã£ã³ã°ãµãŒãã¹ã§ãµããŒããããŠãããããã¢ã¯ã»ã¹ãããããã³ã¹ãå¹æãé«ããšèšãããŠããŸãã
1.3. ãµãŒããŒãµã€ãã¹ã¯ãªãããšããŠã®PHP
ãµãŒããŒãµã€ãã¹ã¯ãªãããšã¯ããŠã§ããµãŒããŒäžã§å®è¡ãããã¹ã¯ãªããã®ããšãæããŸããããã¯ãã¯ã©ã€ã¢ã³ããµã€ãã¹ã¯ãªããïŒäŸ: JavaScriptïŒãšã¯å¯Ÿç §çã§ãã¯ã©ã€ã¢ã³ããµã€ãã¹ã¯ãªããã¯ãŠãŒã¶ãŒã®ãã©ãŠã¶äžã§å®è¡ãããŸããPHPããµãŒããŒãµã€ãã§äœ¿çšããããšã§ãããŒã¿ããŒã¹ãšã®ããåãããã»ãã·ã§ã³ç®¡çããã¡ã€ã«ã®ã¢ããããŒããããŠã³ããŒããªã©ãå€ãã®åçãªæäœãè¡ãããšãã§ããŸãããã®ãããªæäœã¯ãã»ãã¥ãªãã£ãããŒã¿ã®æŽåæ§ãä¿ã€ããã«ãµãŒããŒãµã€ãã§è¡ãããããšãå€ãã§ãã
以äžã®å 容ãããPHPã¯ãŠã§ãéçºã®é åã§éåžžã«åŒ·åã§æè»ãªããŒã«ã§ããããšãããããŸãããã®èµ·æºããçŸåšã®äž»èŠãªçšéãŸã§ãPHPã¯ãŠã§ãæè¡ã®é²åãšãšãã«æé·ãç¶ããŠããŸãã
2. PHP 8ã®æ°æ©èœ
PHP 8ã¯ãPHPã®æŽå²ã®äžã§æã泚ç®ããããªãªãŒã¹ã®äžã€ãšããŠç¥ãããŠããŸãããã®ããŒãžã§ã³ã«ã¯ãéçºè ã®çç£æ§ãšããã©ãŒãã³ã¹ãåäžãããããã®å€ãã®æ°æ©èœãšæ¹åãå«ãŸããŠããŸãã以äžã§ã¯ãPHP 8ã®äž»èŠãªæ°æ©èœã«ã€ããŠè©³ãã説æããŸãã
2.1. Just-in-time (JIT) ã³ã³ãã€ã©
PHP 8ã®æã泚ç®ãããæ°æ©èœã®äžã€ããJust-in-time (JIT) ã³ã³ãã€ã©ã§ããJITã³ã³ãã€ã©ã¯ãPHPã®å®è¡é床ãå€§å¹ ã«åäžãããããšãã§ããŸããåŸæ¥ã®PHPã¯ã€ã³ã¿ãŒããªã¿ãšããŠåäœããŠããŸããããJITã䜿çšãããšãPHPã³ãŒãã¯å®è¡æã«ãã€ãã£ãã®ãã·ã³ã³ãŒãã«å€æãããçŽæ¥å®è¡ãããŸããããã«ãããç¹ã«CPUéçŽçãªã¿ã¹ã¯ã§ã®ããã©ãŒãã³ã¹ãå€§å¹ ã«åäžããŸãã
2.2. ååä»ãåŒæ°
ååä»ãåŒæ°ã¯ãé¢æ°ãã¡ãœãããåŒã³åºãéã«ãåŒæ°ã®ååãæå®ããŠå€ãæž¡ãããšãã§ããæ©èœã§ããããã«ãããé¢æ°ã®ã·ã°ããã£ãå€æŽãããå Žåã§ããåŒæ°ã®é åºã«äŸåããã«ã³ãŒããæžãããšãã§ããŸãããŸããã³ãŒãã®å¯èªæ§ãåäžããã©ã®åŒæ°ãã©ã®å€ã«å¯Ÿå¿ããŠããã®ããäžç®çç¶ãšãªããŸãã
2.3. éçãªæ»ãåãç¶æ¿ãOPcacheæ¡åŒµ
PHP 8ã§ã¯ãéçãªæ»ãåã®ãµããŒããè¿œå ãããŸãããããã«ãããé¢æ°ãã¡ãœããã®æ»ãå€ã®åãããå³å¯ã«æå®ããããšãã§ããŸãããŸããå±æ§ãšããæ°ããæ©èœãå°å ¥ãããã¡ã¿ããŒã¿ãã¯ã©ã¹ãé¢æ°ãããããã£ã«é¢é£ä»ããããšãã§ããããã«ãªããŸãããããã«ãOPcacheæ¡åŒµã¯ãPHPã®ããã©ãŒãã³ã¹ãåäžãããããã®ãã£ãã·ã¥æ©èœãæäŸããŸããããã«ãããã³ã³ãã€ã«æžã¿ã®PHPã³ãŒãããã£ãã·ã¥ããŠåå©çšããããšãã§ãããŠã§ãã¢ããªã±ãŒã·ã§ã³ã®ã¬ã¹ãã³ã¹æéãççž®ããããšãã§ããŸãã
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h2>3. PHPã®åºæ¬çãªããã°ã©ãã³ã°
PHPãåŠã¶éãåºæ¬çãªããã°ã©ãã³ã°ã®æŠå¿µãç解ããããšã¯éåžžã«éèŠã§ãããã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPã®æ žå¿çãªéšåãããªãã¡ããŒã¯ã³ãšæ§æ解æãZend Virtual Machineãšã®é£æºããããŠPHPã©ã€ãã©ãªã®å©çšã«ã€ããŠè©³ãã解説ããŸãã
3.1. ããŒã¯ã³ãšæ§æ解æ
ããã°ã©ã ãæžãéãæã ãå ¥åããã³ãŒãã¯ãå®éã«ã¯ã³ã³ãã¥ãŒã¿ã«ãšã£ãŠç解ãããã圢ã«å€æãããå¿ èŠããããŸãããã®å€æã®éçšã§ãã³ãŒãã¯ããã€ãã®ããŒã¯ã³ã«åå²ãããŸããããŒã¯ã³ãšã¯ãèšèªã®æ§æèŠçŽ ãè¡šãæå°ã®åäœã®ããšãæããŸããäŸãã°ãå€æ°ãé¢æ°åãããŒã¯ãŒããªã©ãããŒã¯ã³ãšããŠèªèãããŸãããããã®ããŒã¯ã³ã¯ãæ§æ解æã®éçšã§ãæ£ããææ³ã«åºã¥ããŠçµã¿ç«ãŠãããŸãã
3.2. Zend Virtual Machineãšã®é£æº
PHPã®ã³ãŒããããŒã¯ã³ã«åå²ãããæ§æ解æããããšã次ã«å®è¡ã®ããã®äžéã³ãŒãã«å€æãããŸãããã®äžéã³ãŒãã¯ãZend Virtual MachineïŒZVMïŒãšããä»®æ³ãã·ã³äžã§å®è¡ãããŸããZVMã¯ãPHPã®ã³ã¢éšåãšããŠåäœããPHPã®é«ãããã©ãŒãã³ã¹ãšå¹çæ§ãå®çŸããŠããŸããZVMã¯ãäžéã³ãŒããçŽæ¥å®è¡ããããšã§ãPHPã®ã¹ã¯ãªãããè¿ éã«åäœããã圹å²ãæãããŠããŸãã
3.3. PHPã©ã€ãã©ãªã®å©çš
PHPã®åŒ·åãªæ©èœã®äžã€ã¯ãè±å¯ãªã©ã€ãã©ãªãšæ¡åŒµæ©èœã®ãµããŒãã§ãããããã®ã©ã€ãã©ãªã¯ãç¹å®ã®ã¿ã¹ã¯ãç°¡åã«å®è¡ããããã®é¢æ°ãã¯ã©ã¹ãæäŸããŠããŸããäŸãã°ãããŒã¿ããŒã¹æäœãXMLã®è§£æãç»ååŠçãªã©ãå€å²ã«ãããã¿ã¹ã¯ãå¹ççã«å®è¡ããããã®ã©ã€ãã©ãªãçšæãããŠããŸããããã«ãããéçºè ã¯è€éãªæäœãç°¡åã«å®è£ ããããšãã§ããéçºã®çç£æ§ãå€§å¹ ã«åäžãããããšãã§ããŸãã
ãã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPã®åºæ¬çãªããã°ã©ãã³ã°ã®æŠå¿µã«ã€ããŠè©³ãã解説ããŸããããããã®æŠå¿µãç解ããããšã§ãPHPã®èåŸã«ããã¡ã«ããºã ããPHPãå¹æçã«äœ¿çšããããã®æ¹æ³ã«ã€ããŠã®ç解ãæ·±ãŸãã§ãããã
4. PHPã䜿çšãããŠã§ãéçºã®å®äŸ
PHPã¯ããã®æè»æ§ãšæ¡åŒµæ§ã®ããããŠã§ãéçºã®ããŸããŸãªã·ããªãªã§äœ¿çšãããŠããŸãããã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPã䜿çšãããŠã§ãéçºã®å ·äœçãªå®äŸãããã€ãåãäžãããã®å®è£ æ¹æ³ãå©ç¹ã«ã€ããŠè©³ãã解説ããŸãã
4.1. ãã€ãããã¯ãªã³ã³ãã³ãã®çæ
ãŠã§ããµã€ãã®äž»èŠãªé åã®äžã€ã¯ããã€ãããã¯ãªã³ã³ãã³ããæäŸããèœåã§ããPHPã¯ããŠãŒã¶ãŒã®å ¥åãããŒã¿ããŒã¹ã®æ å ±ã«åºã¥ããŠããªã¢ã«ã¿ã€ã ã§ããŒãžã®å 容ãå€æŽããããšãã§ããŸããäŸãã°ããªã³ã©ã€ã³ã·ã§ããã³ã°ãµã€ãã§ã¯ããŠãŒã¶ãŒãæ€çŽ¢ããã¯ã¹ã«ããŒã¯ãŒããå ¥åãããšãé¢é£ããååã®ãªã¹ãã衚瀺ãããŸãããã®ãããªåçãªã³ã³ãã³ãã®çæã¯ãPHPã®åŒ·åãªæ©èœã掻çšããŠå®çŸãããŠããŸãã
4.2. ããŒã¿ããŒã¹ãšã®é£æº
ã»ãšãã©ã®ãŠã§ãã¢ããªã±ãŒã·ã§ã³ã¯ãããŒã¿ããŒã¹ãšé£æºããŠåäœããŠããŸããPHPã¯ãMySQLãPostgreSQLãªã©ã®äººæ°ã®ããããŒã¿ããŒã¹ã·ã¹ãã ãšã®é£æºã容æã§ãããŠãŒã¶ãŒã®ã¢ã«ãŠã³ãæ å ±ãååã®åšåº«æ å ±ãããã°ã®èšäºãªã©ãããŸããŸãªããŒã¿ãããŒã¿ããŒã¹ã«ä¿åããå¿ èŠã«å¿ããŠååŸããããšãã§ããŸããPHPã®ããŒã¿ããŒã¹é¢é£ã®é¢æ°ã䜿çšããããšã§ãããŒã¿ã®è¿œå ãæŽæ°ãåé€ãªã©ã®æäœãç°¡åã«è¡ãããšãã§ããŸãã
4.3. ãŠãŒã¶ãŒã»ãã·ã§ã³ãã©ããã³ã°
ãŠã§ãã¢ããªã±ãŒã·ã§ã³ã§ã¯ããŠãŒã¶ãŒã®è¡åãéžæã远跡ããããšããã°ãã°å¿ èŠãšãªããŸããPHPã¯ãã»ãã·ã§ã³ç®¡çã®æ©èœãæäŸããŠããããŠãŒã¶ãŒããµã€ããé¢ããŠããã®æ å ±ãä¿æããããšãã§ããŸããããã«ãããã·ã§ããã³ã°ã«ãŒãã®å 容ã®ä¿åãããã°ã€ã³ç¶æ ã®ç¶æãªã©ããŠãŒã¶ãŒã«ãšã£ãŠäŸ¿å©ãªæ©èœãå®çŸããããšãã§ããŸãã
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5. PHPã®å¿çš
PHPã¯ãŠã§ãéçºã ãã§ãªããããŸããŸãªå¿çšåéã§ã®äœ¿çšãå¢ããŠããŠããŸãããã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPã®å é²çãªå¿çšäŸãããã€ãåãäžãããã®å®è£ æ¹æ³ãå©ç¹ã«ã€ããŠè©³ãã解説ããŸãã
5.1. IoTãããã€ã¡ã³ã
è¿å¹ŽãIoTïŒInternet of ThingsïŒãšããèšèãããè³ã«ããããã«ãªããŸãããããã¯ãããŸããŸãªããã€ã¹ãã€ã³ã¿ãŒãããã«æ¥ç¶ãããããŒã¿ãåéã»å ±æããããšãæããŸããPHPã¯ãIoTããã€ã¹ããã®ããŒã¿ãåéããããããŠã§ãã€ã³ã¿ãŒãã§ãŒã¹ã§è¡šç€ºããããã®ããã¯ãšã³ããšããŠäœ¿çšãããããšãå¢ããŠããŠããŸããäŸãã°ãæ°æž©ã湿床ã»ã³ãµãŒããã®ããŒã¿ããªã¢ã«ã¿ã€ã ã§ãŠã§ãããŒãžã«è¡šç€ºããããšãå¯èœã§ãã
5.2. æ©æ¢°åŠç¿ã¢ãã«
æ©æ¢°åŠç¿ã¯ãããŒã¿ããåŠç¿ããŠäºæž¬ãåé¡ãè¡ãæè¡ã§ããPHPã¯ãæ©æ¢°åŠç¿ã¢ãã«ã®çµæããŠã§ãã€ã³ã¿ãŒãã§ãŒã¹ã§è¡šç€ºããããã®ããã¯ãšã³ããšããŠäœ¿çšãããããšããããŸããäŸãã°ããŠãŒã¶ãŒã®è¡åã«åºã¥ããŠååã®æšèŠãè¡ããªã³ã©ã€ã³ã·ã§ããã³ã°ãµã€ããªã©ã§ãæ©æ¢°åŠç¿ã¢ãã«ã®çµæã掻çšããŠããŸãã
5.3. WebAssemblyãšã®é¢é£æ§
WebAssemblyã¯ããŠã§ããã©ãŠã¶äžã§é«éã«å®è¡ã§ãããã€ããªãã©ãŒãããã§ããPHPãšWebAssemblyãçµã¿åãããããšã§ããŠã§ãã¢ããªã±ãŒã·ã§ã³ã®ããã©ãŒãã³ã¹ãå€§å¹ ã«åäžãããããšãã§ããŸããPHPã¯ãWebAssemblyã¢ãžã¥ãŒã«ãåŒã³åºãããã®çµæããŠã§ãããŒãžã«è¡šç€ºããããã®ããã¯ãšã³ããšããŠæ©èœããŸãã
ãã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPã®å é²çãªå¿çšäŸã«ã€ããŠè©³ãã解説ããŸããããããã®å¿çšäŸãéããŠãPHPã®å€æ§æ§ãšãã®å®çšæ§ãããã«æ·±ãç解ããããšãã§ããã§ãããã
6. PHPã®åŠç¿ãªãœãŒã¹
PHPã®åŠç¿ã¯ãé©åãªãªãœãŒã¹ãå©çšããããšã§ãå¹ççãã€æ¥œããé²ããããšãã§ããŸãããã®ã»ã¯ã·ã§ã³ã§ã¯ãPHPãåŠã¶ããã®ããããã®ãªãœãŒã¹ããå®è·µçãªãããžã§ã¯ãã®ã¢ã€ãã£ã¢ãããã«ã¯ãµããŒããåããããã®ã³ãã¥ããã£ã«ã€ããŠè©³ãã玹ä»ããŸãã
6.1. ããããã®æžç±ãšãŠã§ããµã€ã
PHPã«é¢ããæžç±ã¯æ°å€ãåºçãããŠãããåå¿è ããäžçŽè ãŸã§å¹ åºãèªè ã察象ãšãããã®ããããŸããç¹ã«ãåºç€ãããã£ãããšåŠã³ããæ¹ã«ã¯ã詳现ãªè§£èª¬ãå®äŸãè±å¯ã«æ²èŒãããŠããæžç±ãããããã§ãããŸãããŠã§ããµã€ããåŠç¿ã®äžç°ãšããŠéåžžã«åœ¹ç«ã¡ãŸããå ¬åŒããã¥ã¡ã³ãããã¥ãŒããªã¢ã«ããã©ãŒã©ã ãªã©ãããŸããŸãªæ å ±ãç¡æã§æäŸãããŠããŸãã
6.2. å®è·µçãªãããžã§ã¯ãã®ã¢ã€ãã£ã¢
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6.3. ã³ãã¥ããã£ãšãµããŒã
PHPã®åŠç¿ãé²ããäžã§ãçåãå°é£ã«çŽé¢ããããšãããã§ãããããããªãšãã«ã¯ãã³ãã¥ããã£ã®åãåããããšãããããã§ããäžçäžã«æ°å€ãã®PHPã³ãã¥ããã£ãååšããŠãããçµéšè±å¯ãªéçºè ãã¡ãã¢ããã€ã¹ããµããŒããæäŸããŠããŸãããã©ãŒã©ã ãã¡ãŒãªã³ã°ãªã¹ããå匷äŒãªã©ãããŸããŸãªåœ¢ã§æ å ±äº€æããããã¯ãŒãã³ã°ã®å ŽãæäŸãããŠããŸãã
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7. ãŸãšã
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