eslint/no-implicit-coercion Style
What it does
Disallow shorthand type conversions using operators like !!, unary +, and "" +.
Why is this bad?
Implicit type coercions using operators can be less clear than using explicit type conversion functions like Boolean(), Number(), and String(). Using explicit conversions makes the intent clearer and the code more readable.
Examples
Examples of incorrect code for this rule:
var b = !!foo;
var n = +foo;
var s = "" + foo;Examples of correct code for this rule:
var b = Boolean(foo);
var n = Number(foo);
var s = String(foo);Configuration
This rule accepts a configuration object with the following properties:
allow
type: string[]
List of operators to allow. Valid values: "!!", "~", "+", "-", "- -", "*"
boolean
type: boolean
default: true
When true, warns on implicit boolean coercion (e.g., !!foo).
disallowTemplateShorthand
type: boolean
default: false
When true, disallows using template literals for string coercion (e.g., `${foo}`).
number
type: boolean
default: true
When true, warns on implicit number coercion (e.g., +foo).
string
type: boolean
default: true
When true, warns on implicit string coercion (e.g., "" + foo).
How to use
To enable this rule using the config file or in the CLI, you can use:
{
"rules": {
"no-implicit-coercion": "error"
}
}import { defineConfig } from "oxlint";
export default defineConfig({
rules: {
"no-implicit-coercion": "error",
},
});oxlint --deny no-implicit-coercionVersion
This rule was added in v1.33.0.