regexNamedReplacements

Reports indexed references in replacement strings that should use named references.

✅ This rule is included in the ts stylisticStrict presets.

When using String.prototype.replace() or String.prototype.replaceAll() with a regular expression that has named capturing groups, the replacement string should use named references ($<name>) instead of indexed references ($1, $2, etc.).

Named references make the code more self-documenting and less prone to errors when the regex pattern is modified.

const 
const result: string
result = "str".
String.replace(searchValue: {
    [Symbol.replace](string: string, replaceValue: string): string;
}, replaceValue: string): string (+3 overloads)
Passes a string and
{@linkcode
replaceValue
}
to the [Symbol.replace] method on
{@linkcode
searchValue
}
. This method is expected to implement its own replacement algorithm.
@param ― searchValue An object that supports searching for and replacing matches within a string.
@param ― replaceValue The replacement text.
replace(/a(?<name>b)c/, "_$1_");

const 
const result: string
result = "2024-01-15".
String.replace(searchValue: {
    [Symbol.replace](string: string, replaceValue: string): string;
}, replaceValue: string): string (+3 overloads)
Passes a string and
{@linkcode
replaceValue
}
to the [Symbol.replace] method on
{@linkcode
searchValue
}
. This method is expected to implement its own replacement algorithm.
@param ― searchValue An object that supports searching for and replacing matches within a string.
@param ― replaceValue The replacement text.
replace(
  /(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/,
  "$2/$3/$1",
);

const 
const result: string
result = "str".
String.replace(searchValue: {
    [Symbol.replace](string: string, replaceValue: string): string;
}, replaceValue: string): string (+3 overloads)
Passes a string and
{@linkcode
replaceValue
}
to the [Symbol.replace] method on
{@linkcode
searchValue
}
. This method is expected to implement its own replacement algorithm.
@param ― searchValue An object that supports searching for and replacing matches within a string.
@param ― replaceValue The replacement text.
replace(/a(?<name>b)c/, "_$<name>_");

const 
const result: string
result = "2024-01-15".
String.replace(searchValue: {
    [Symbol.replace](string: string, replaceValue: string): string;
}, replaceValue: string): string (+3 overloads)
Passes a string and
{@linkcode
replaceValue
}
to the [Symbol.replace] method on
{@linkcode
searchValue
}
. This method is expected to implement its own replacement algorithm.
@param ― searchValue An object that supports searching for and replacing matches within a string.
@param ― replaceValue The replacement text.
replace(
  /(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/,
  "$<month>/$<day>/$<year>",
);

// Unnamed groups can use indexed references
const 
const result: string
result = "str".
String.replace(searchValue: {
    [Symbol.replace](string: string, replaceValue: string): string;
}, replaceValue: string): string (+3 overloads)
Passes a string and
{@linkcode
replaceValue
}
to the [Symbol.replace] method on
{@linkcode
searchValue
}
. This method is expected to implement its own replacement algorithm.
@param ― searchValue An object that supports searching for and replacing matches within a string.
@param ― replaceValue The replacement text.
replace(/a(b)c/, "_$1_");

Options

This rule is not configurable.

When Not To Use It

If you prefer the brevity of indexed replacements, or if your codebase has established conventions around using indexed references even for named groups, you might prefer to disable this rule. Some developers find indexed references more familiar from other regex dialects.

Equivalents in Other Linters

ESLint: regexp/prefer-named-replacement

Made with ❤️‍🔥 around the world by the Flint team and contributors.

regexNamedReplacements

Examples

Options

When Not To Use It

Further Reading

Equivalents in Other Linters