2nd/10_Wiki/Dev/Topic_PHP/PHP_String_Concatenate.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-string-concatenate	PHP String Concatenate	Programming_Language	draft	conceptual		. operator PHP 문자열 연결		B	0.9	2026-07-04	2026-07-04			php programming w3schools strings concatenation	https://www.w3schools.com/php/php_string_concatenate.asp

PHP String Concatenate

🎯 한 줄 통찰 (One-line insight)

PHP's concatenation operator is . (a period), NOT + like many other languages — this is a common source of confusion for developers coming from JavaScript or Python, and joining two strings with . produces zero implicit spacing ("Hello" . "World" gives "HelloWorld", not "Hello World"). [S1]

🧠 핵심 개념 (Core concepts)

• . operator — concatenates (joins) two strings. [S1]
• No implicit spacing — $x . $y gives no space between values; must explicitly add " ". [S1]
• Double-quote interpolation as an alternative — "$x $y" embeds both variables with a literal space, avoiding the . operator entirely. [S1]

📖 세부 내용 (Details)

• Basic concat (no space): $x = "Hello"; $y = "World"; $z = $x . $y; echo $z; // "HelloWorld". [S1]
• With explicit space: $z = $x . " " . $y; echo $z; // "Hello World". [S1]
• Interpolation alternative: $z = "$x $y"; echo $z; // "Hello World". [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

소스에서 모순되는 정보는 발견되지 않음.

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 큰따옴표 보간을 활용해 . 연산자 없이 두 변수를 결합하는 방식이 더 간결한 대안으로 제시된다. [S1]

💻 코드 패턴 (Code patterns)

Concatenation with explicit space vs. double-quote interpolation (PHP):

$x = "Hello";
$y = "World";
$z = $x . " " . $y;  // "Hello World" via . operator
$z2 = "$x $y";        // "Hello World" via interpolation

✅ 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 Strings, PHP String Modify, PHP String Slicing
• 참조 맥락: 문자열 결합 연산자 — 슬라이싱(Slicing) 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — PHP - Concatenate Strings — https://www.w3schools.com/php/php_string_concatenate.asp

📝 변경 이력 (Change history)

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