2nd/10_Wiki/Dev/Topic_PHP/PHP_Includes.md

id, title, category, status, verification_status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, created_at, updated_at, review_reason, merge_history, tags, raw_sources, applied_in, github_commit

id	title	category	status	verification_status	canonical_id	aliases	duplicate_of	source_trust_level	confidence_score	created_at	updated_at	review_reason	merge_history	tags	raw_sources	applied_in	github_commit
php-includes	PHP Includes	Programming_Language	draft	conceptual		include vs require PHP 파일 포함		B	0.9	2026-07-04	2026-07-04			php programming w3schools include require	https://www.w3schools.com/php/php_includes.asp

PHP Includes

🎯 한 줄 통찰 (One-line insight)

include and require behave identically on SUCCESS but diverge sharply on FAILURE — a missing file only produces a warning with include (script continues, later code still runs), while the same missing file with require triggers a fatal error that halts script execution entirely, making the choice a statement about how critical that file is to the page working at all. [S1]

🧠 핵심 개념 (Core concepts)

• include 'file'; / require 'file'; — insert a file's content into the calling file. [S1]
• Failure behavior difference — include → E_WARNING, script continues; require → E_ERROR (fatal), script stops. [S1]
• When to use include — non-critical files like headers, footers, navigation menus (page can still render without them). [S1]
• When to use require — critical files like configuration or database connections (page is meaningless without them). [S1]
• Included files share variable scope — variables defined in an included file become usable in the calling file. [S1]

📖 세부 내용 (Details)

• Include a footer: <?php include 'footer.php';?>. [S1]
• Include a nav menu: <div class="menu"><?php include 'menu.php';?></div>. [S1]
• Include shares variables: vars.php defines $color='red'; $car='BMW';; the including file can then echo "I have a $color $car."; after include 'vars.php';. [S1]
• include on missing file (continues): <?php include 'noFileExists.php'; echo "I have a $color $car."; ?> — the echo still runs (with warning), though $color/$car are undefined here since the file wasn't found. [S1]
• require on missing file (halts): <?php require 'noFileExists.php'; echo "I have a $color $car."; ?> — the echo NEVER executes; script dies at the require line. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• 실패 시 동작의 근본적 차이: include는 경고만 내고 스크립트가 계속 실행되지만, require는 치명적 에러를 내고 스크립트 실행이 완전히 중단된다는 점이 대비 예제로 직접 증명됨. [S1]

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 모든 페이지가 공유하는 표준 헤더/푸터/메뉴 파일을 include로 재사용하는 것이 실전 코드 재사용의 대표 패턴이다. [S1]

💻 코드 패턴 (Code patterns)

require halts execution on failure, unlike include (PHP):

<?php require 'noFileExists.php'; // fatal error — script dies here
echo "This line never runs.";
?>

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.90
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: PHP Tutorial
• 관련 개념: PHP Date, PHP Files, PHP Variables Scope
• 참조 맥락: 코드 재사용을 위한 파일 포함 — 파일 처리(Files) 섹션으로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — PHP Include Files — https://www.w3schools.com/php/php_includes.asp

📝 변경 이력 (Change history)

• 2026-07-04: Initial draft synthesized from the W3Schools "PHP Include Files" page (Astra wiki-curation, P-Reinforce v3.1 format).