2nd/10_Wiki/Dev/Topic_CPP/CPP_Conditions_Nested.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
cpp-conditions-nested	C++ Nested If	Programming_Language	draft	conceptual		if inside if dependent conditions C++ 중첩 if		B	0.83	2026-07-04	2026-07-04			cpp programming-language w3schools conditions nested-if	https://www.w3schools.com/cpp/cpp_conditions_nested.asp

CPP Nested If

🎯 한 줄 통찰 (One-line insight)

The same short-circuit benefit from C's Nested If chapter applies unchanged — the citizenship check (isCitizen) is never even evaluated if age >= 18 is false, meaning nesting still functions as a genuine short-circuit optimization in C++, not just visual grouping of related checks. [S1]

🧠 핵심 개념 (Core concepts)

• Nested if — placing an if inside another if's block, so the inner condition is only checked when the outer condition already holds. [S1]
• Dependent condition modeling — naturally expresses "check B only if A holds." [S1]
• Depth caution — avoid nesting too deeply, as it hurts readability; often combined with else/else if. [S1]

📖 세부 내용 (Details)

• Basic two-level nesting: int x = 15; int y = 25; if (x > 10) { cout << "x is greater than 10\n"; if (y > 20) { cout << "y is also greater than 20\n"; } }. [S1]
• Voting + citizenship real-life example: int age = 20; bool isCitizen = true; if (age >= 18) { cout << "Old enough to vote.\n"; if (isCitizen) { cout << "And you are a citizen, so you can vote!\n"; } else { cout << "But you must be a citizen to vote.\n"; } } else { cout << "Not old enough to vote.\n"; }. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• 현재까지 발견된 모순 사항 없음 (No contradictions found in available sources). C 챕터와 동일한 중첩 if 및 단축 평가 특성이 확인됨.

🛠️ 적용 사례 (Applied in summary)

투표 가능 연령(18세 이상)을 먼저 확인하고, 그 안에서만 시민권 여부를 추가로 확인하는 예제가 원문에서 직접 실전 활용 사례로 제시됨. [S1]

💻 코드 패턴 (Code patterns)

An inner condition (citizenship) checked only when the outer condition (age) already holds (C++):

int age = 20;
bool isCitizen = true;
if (age >= 18) {
  cout << "Old enough to vote.\n";
  if (isCitizen) {
    cout << "And you are a citizen, so you can vote!\n";
  } else {
    cout << "But you must be a citizen to vote.\n";
  }
} else {
  cout << "Not old enough to vote.\n";
}

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.83
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: C++ Tutorial
• 관련 개념: CPP Conditions Logical, CPP Conditions RealLife, C Conditions Nested
• 참조 맥락: 중첩 if — 조건문 실전 예제(Conditions RealLife) 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — C++ Nested If — https://www.w3schools.com/cpp/cpp_conditions_nested.asp

📝 변경 이력 (Change history)

• 2026-07-04: Initial draft synthesized from the W3Schools "C++ Nested If" page (Astra wiki-curation, P-Reinforce v3.1 format).