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numberMethodRanges

Reports when number method arguments are outside their valid range.

✅ This rule is included in the ts logical and logicalStrict presets.

Number methods such as toExponential, toFixed, toPrecision, and toString have specific valid ranges for their arguments. Passing values outside these ranges will throw a RangeError at runtime.

This rule flags numeric literal arguments that are outside the valid range:

  • Number.prototype.toExponential(digits): digits must be between 0 and 100
  • Number.prototype.toFixed(digits): digits must be between 0 and 100
  • Number.prototype.toPrecision(precision): precision must be between 1 and 100
  • Number.prototype.toString(radix): radix must be between 2 and 36

Examples

Section titled “Examples”
const 
const binary: string
binary = (255).
Number.toString(radix?: number): string
Returns a string representation of an object.
@param ― radix Specifies a radix for converting numeric values to strings. This value is only used for numbers.
toString(1);
const 
const hex: string
hex = (255).
Number.toString(radix?: number): string
Returns a string representation of an object.
@param ― radix Specifies a radix for converting numeric values to strings. This value is only used for numbers.
toString(37);
const 
const fixed: string
fixed = (3.14159).
Number.toFixed(fractionDigits?: number): string
Returns a string representing a number in fixed-point notation.
@param ― fractionDigits Number of digits after the decimal point. Must be in the range 0 - 20, inclusive.
toFixed(101);
const 
const exponential: string
exponential = (12345).
Number.toExponential(fractionDigits?: number): string
Returns a string containing a number represented in exponential notation.
@param ― fractionDigits Number of digits after the decimal point. Must be in the range 0 - 20, inclusive.
toExponential(-1);
const 
const precision: string
precision = (12345).
Number.toPrecision(precision?: number): string
Returns a string containing a number represented either in exponential or fixed-point notation with a specified number of digits.
@param ― precision Number of significant digits. Must be in the range 1 - 21, inclusive.
toPrecision(0);

Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If your codebase is a rare one that overrides those native methods, this rule might not be for you.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”
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