2nd/10_Wiki/Dev/Topic_PHP/PHP_Looping_For.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-looping-for	PHP Looping For	Programming_Language	draft	conceptual		for loop PHP for 반복문		B	0.9	2026-07-04	2026-07-04			php programming w3schools loops for	https://www.w3schools.com/php/php_looping_for.asp

PHP Looping For

🎯 한 줄 통찰 (One-line insight)

The for loop's three clauses each run at a different time relative to the loop body — initialization runs ONCE before anything, the condition runs BEFORE each iteration, and the increment runs AFTER each iteration — meaning changing the increment direction ($x++ to $x--) alone, combined with a matching condition, is all that's needed to count backwards instead of forwards. [S1]

🧠 핵심 개념 (Core concepts)

• for (init; condition; increment) { ... } — init runs once; condition checked before each iteration; increment runs after each iteration. [S1]
• Use case — when the number of iterations is known ahead of time. [S1]
• Counting down — reversing the increment ($x--) and flipping the condition ($x >= 0). [S1]
• break / continue — work the same as other loop types. [S1]
• Custom step size — $x += 10 for stepping by 10 instead of 1. [S1]

📖 세부 내용 (Details)

• Counting up: for ($x = 0; $x <= 10; $x++) { echo "The number is: $x <br>"; }. [S1]
• Counting down: for ($x = 10; $x >= 0; $x--) { echo "The number is: $x <br>"; }. [S1]
• Break: for ($x = 0; $x <= 10; $x++) { if ($x == 3) break; echo "The number is: $x <br>"; }. [S1]
• Continue: for ($x = 0; $x <= 10; $x++) { if ($x == 3) continue; echo "The number is: $x <br>"; }. [S1]
• Step 10: for ($x = 0; $x <= 100; $x += 10) { echo "The number is: $x <br>"; }. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

소스에서 모순되는 정보는 발견되지 않음.

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 10부터 0까지 카운트다운하는 예제가 증감 방향 조정의 대표 패턴이다. [S1]

💻 코드 패턴 (Code patterns)

Counting down with a for loop (PHP):

for ($x = 10; $x >= 0; $x--) {
    echo "The number is: $x <br>";
}

✅ 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 Looping Do While, PHP Looping Foreach, PHP Looping Break
• 참조 맥락: 반복 횟수를 아는 경우의 표준 반복문 — foreach 루프 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — PHP for Loop — https://www.w3schools.com/php/php_looping_for.asp

📝 변경 이력 (Change history)

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