2nd/10_Wiki/Topics/Domain_Programming/Topic_JavaScript/JavaScript_Statements.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
javascript-statements	JavaScript Statements	Frontend	draft	conceptual		JS statements semicolons code blocks white space JS keywords		B	0.88	2026-06-23	2026-06-23			javascript js web frontend w3schools statements semicolons	https://www.w3schools.com/js/js_statements.asp

JavaScript Statements

🎯 한 줄 통찰 (One-line insight)

A JavaScript program is a list of statements — composed of values, operators, expressions, keywords, and comments — executed in the order they are written and separated by semicolons. [S1]

🧠 핵심 개념 (Core concepts)

• A program is a list of statements — a computer program is a list of "instructions" to be "executed" by a computer; in JavaScript these instructions are called statements. [S1]
• What statements are made of — values, operators, expressions, keywords, and comments. [S1]
• Semicolons separate statements — semicolons separate JavaScript statements; multiple statements on one line are allowed when separated by semicolons. [S1]
• White space is ignored — JavaScript ignores multiple spaces; add spaces around operators for readability. [S1]
• Line breaks — for best readability, keep lines under 80 characters and break after an operator. [S1]
• Code blocks — statements can be grouped together in code blocks inside curly brackets { ... }, typically defining functions. [S1]

🧩 추출된 패턴 (Extracted patterns)

• Declare-then-assign sequence — declare variables, then assign and compute across ordered statements. [S1]
• One-line grouping — multiple statements may be packed on a single line with semicolons (a = 5; b = 6; c = a + b;). [S1]
• Break-after-operator — when a statement is too long, break the line after an operator. [S1]
• Block grouping — wrap related statements in { } to form a function body executed together. [S1]

📖 세부 내용 (Details)

JavaScript Programs — A computer program is a list of "instructions" to be "executed" by a computer. In a programming language, these programming instructions are called statements. A JavaScript program is a list of programming statements. In HTML, JavaScript programs are executed by the web browser. [S1]

JavaScript Statements — JavaScript statements are composed of values, operators, expressions, keywords, and comments. This statement tells the browser to write "Hello Dolly." inside an HTML element with id="demo": [S1]

document.getElementById("demo").innerHTML = "Hello Dolly.";

Most JavaScript programs contain many JavaScript statements, executed in the same order as they are written: [S1]

let x, y, z;    // Statement 1
x = 5;          // Statement 2
y = 6;          // Statement 3
z = x + y;      // Statement 4

Semicolons ; — Semicolons separate JavaScript statements. Add a semicolon at the end of each executable statement: [S1]

let a, b, c;  // Declare 3 variables
a = 5;        // Assign the value 5 to a
b = 6;        // Assign the value 6 to b
c = a + b;    // Assign the sum of a and b to c

When separated by semicolons, multiple statements on one line are allowed: [S1]

a = 5; b = 6; c = a + b;

JavaScript White Space — JavaScript ignores multiple spaces. You can add white space to your script to make it more readable. A good practice is to put spaces around operators (= + - * /). [S1]

JavaScript Line Length and Line Breaks — For best readability, programmers often like to avoid code lines longer than 80 characters. If a JavaScript statement does not fit on one line, the best place to break it is after an operator: [S1]

document.getElementById("demo").innerHTML =
"Hello Dolly!";

JavaScript Code Blocks — JavaScript statements can be grouped together in code blocks, inside curly brackets {...}. The purpose of code blocks is to define statements to be executed together. One place you will find statements grouped together in blocks is in JavaScript functions: [S1]

function myFunction() {
  document.getElementById("demo1").innerHTML = "Hello Dolly!";
  document.getElementById("demo2").innerHTML = "How are you?";
}

JavaScript Keywords — JavaScript statements often start with a keyword to identify the JavaScript action to be performed. The following table lists some of the keywords: [S1]

Keyword	Description
var	Declares a variable
let	Declares a block variable
const	Declares a block constant
if	Marks a block of statements to be executed on a condition
switch	Marks a block of statements to be executed in different cases
for	Marks a block of statements to be executed in a loop
function	Declares a function
return	Exits a function
try	Implements error handling to a block of statements

JavaScript keywords are reserved words and cannot be used as names for variables. [S1]

🛠️ 적용 사례 (Applied in summary)

The page's own snippets are the canonical applied examples — the ordered let x, y, z / assign / sum statements, the one-line a = 5; b = 6; c = a + b;, the operator line break, and the two-statement function block. No external project/commit applications found in the source.

💻 코드 패턴 (Code patterns)

Ordered statements:

let x, y, z;
x = 5;
y = 6;
z = x + y;

Code block (function):

function myFunction() {
  document.getElementById("demo1").innerHTML = "Hello Dolly!";
  document.getElementById("demo2").innerHTML = "How are you?";
}

⚖️ 모순 및 업데이트 (Contradictions & updates)

No contradictions found in the source.

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual (실제 적용 사례 발견 시 applied/validated로 승격 가능)
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.88
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: JavaScript Tutorial
• 관련 개념: JavaScript Syntax, JavaScript Comments, JavaScript Variables
• 참조 맥락: Defines the unit of execution referenced by every later control-flow and function topic.

📚 출처 (Sources)

• [S1] W3Schools — JavaScript Statements — https://www.w3schools.com/js/js_statements.asp

📝 변경 이력 (Change history)

• 2026-06-23: Initial draft synthesized from the W3Schools "JavaScript Statements" page (Astra wiki-curation, P-Reinforce v3.1 format).