2nd/10_Wiki/Dev/Topic_C/C_Conditions.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
c-conditions	C If ... Else	Programming_Language	draft	conceptual		if statement lowercase if C 조건문		B	0.86	2026-07-04	2026-07-04			c programming-language w3schools conditions if-statement	https://www.w3schools.com/c/c_conditions.php

C If ... Else

🎯 한 줄 통찰 (One-line insight)

Case sensitivity isn't just a general C rule mentioned in passing — this chapter singles it out specifically for if, explicitly warning that If or IF will generate an error, meaning the keyword has zero tolerance for capitalization variants despite if being one of the most frequently typed words in any C program. [S1]

🧠 핵심 개념 (Core concepts)

• Six comparison conditions — <, <=, >, >=, ==, !=, familiar from mathematics. [S1]
• Four conditional constructs — if (run code if true), else (run if false), else if (test a new condition if the first is false), switch (many alternative code blocks). [S1]
• Case-sensitive keyword — if must be lowercase; If/IF produce an error. [S1]
• Boolean-variable readability pattern — storing a comparison's result in a bool variable before using it in if makes complex or reused conditions easier to read. [S1]

📖 세부 내용 (Details)

• Basic if with literal values: if (20 > 18) { printf("20 is greater than 18"); }. [S1]
• If with variables: int x = 20; int y = 18; if (x > y) { printf("x is greater than y"); }. [S1]
• Using a boolean variable to hold the condition: bool isGreater = x > y; if (isGreater) { printf("x is greater than y"); } (requires <stdbool.h>). [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• if는 반드시 소문자: If나 IF처럼 대소문자를 다르게 쓰면 에러가 발생한다는 점이 명시적으로 경고됨. [S1]

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 복잡하거나 재사용되는 조건을 bool 변수에 미리 담아두는 패턴이 가독성 있는 조건문 작성의 실전 관행이다. [S1]

💻 코드 패턴 (Code patterns)

Storing a condition in a readable boolean variable before using it in an if statement (C):

int x = 20;
int y = 18;
bool isGreater = x > y;
if (isGreater) {
  printf("x is greater than y");
}

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.86
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: C Tutorial
• 관련 개념: C Booleans RealLife, C Conditions Else
• 참조 맥락: 조건문 섹션 첫 챕터 — else 문(Conditions Else) 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — C If ... Else — https://www.w3schools.com/c/c_conditions.php

📝 변경 이력 (Change history)

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