noConstantCondition

诊断类别：lint/correctness/noConstantCondition

¥Diagnostic Category: lint/correctness/noConstantCondition

JavaScript (and super languages)

自从：v1.0.0

¥Since: v1.0.0

来源：

¥Sources:

与以下相同：no-constant-condition

¥Same as: no-constant-condition

禁止在条件中使用常量表达式

¥Disallow constant expressions in conditions

示例

¥Examples

无效

¥Invalid

if (false) {
    doSomethingUnfinished();
}

code-block.js:1:5 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ if (false) {
      │     ^^^^^
    2 │     doSomethingUnfinished();
    3 │ }

if (Boolean(1)) {
    doSomethingAlways();
}

code-block.js:1:5 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ if (Boolean(1)) {
      │     ^^^^^^^^^^
    2 │     doSomethingAlways();
    3 │ }

if (undefined) {
    doSomethingUnfinished();
}

code-block.js:1:5 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ if (undefined) {
      │     ^^^^^^^^^
    2 │     doSomethingUnfinished();
    3 │ }

for (;-2;) {
    doSomethingForever();
}

code-block.js:1:7 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ for (;-2;) {
      │       ^^
    2 │     doSomethingForever();
    3 │ }

while (typeof x) {
    doSomethingForever();
}

code-block.js:1:8 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ while (typeof x) {
      │        ^^^^^^^^
    2 │     doSomethingForever();
    3 │ }

var result = 0 ? a : b;

code-block.js:1:14 lint/correctness/noConstantCondition ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Unexpected constant condition.
  
  > 1 │ var result = 0 ? a : b;
      │              ^
    2 │

有效

¥Valid

if (x === 0) {
    doSomething();
}

for (;;) {
    doSomethingForever();
}

while (typeof x === "undefined") {
    doSomething();
}

do {
    doSomething();
} while (x);

var result = x !== 0 ? a : b;

// Exception
while (true) {
    if (x) { break; }
    x = f();
}

noConstantCondition

示例

无效

有效

相关链接