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useWhile

Diagnostic Category: lint/style/useWhile

Since: v1.0.0

Sources:

Description

Section titled Description

Enforce the use of while loops instead of for loops when the initializer and update expressions are not needed.

Examples

Section titled Examples

Invalid

Section titled Invalid
for (; x.running;) {
    x.step();
}
code-block.js:1:1 lint/style/useWhile  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Use a while loop instead of a for loop.
  
  > 1 │ for (; x.running;) {
      │ ^^^^^^^^^^^^^^^^^^
    2 │     x.step();
    3 │ }
  
  ℹ Prefer a while loop over a for loop without initialization and update.
  
  ℹ Safe fix: Use a while loop.
  
    1   │ - for·(;·x.running;)·{
      1 │ + while·(x.running)·{
    2 2 │       x.step();
    3 3 │   }

Valid

Section titled Valid
for(let x = 0; x < 10; i++) {}
let x = 0
for(; x < 10; i++) {}
for(let x = 0; x < 10;) {
    i++
}

How to configure

Section titled How to configure
biome.json
{
  "linter": {
    "rules": {
      "style": {
        "useWhile": "error"
      }
    }
  }
}
Section titled Related links