regexLiterals

Use a regular expression literal when the pattern is static.

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

When the pattern and flags are static strings, using a regex literal is more concise and avoids unnecessary constructor calls. Regex literals are also easier to read and cannot throw at runtime due to invalid patterns, since they are validated at parse time.

const 
const pattern: RegExp
pattern = 
var RegExp: RegExpConstructor
(pattern: RegExp | string, flags?: string) => RegExp (+2 overloads)
RegExp("abc");

const 
const pattern: RegExp
pattern = new 
var RegExp: RegExpConstructor
new (pattern: RegExp | string, flags?: string) => RegExp (+2 overloads)
RegExp("abc", "gi");

const 
const pattern: RegExp
pattern = 
var RegExp: RegExpConstructor
(pattern: RegExp | string, flags?: string) => RegExp (+2 overloads)
RegExp("");

const 
const pattern: RegExp
pattern = /abc/;

const 
const pattern: RegExp
pattern = /abc/gi;

const 
const pattern: RegExp
pattern = /(?:)/;

// Dynamic patterns are fine
const 
const pattern: RegExp
pattern = new 
var RegExp: RegExpConstructor
new (pattern: RegExp | string, flags?: string) => RegExp (+2 overloads)
RegExp(
const userInput: string
userInput);

// Dynamic flags are fine
const 
const pattern: RegExp
pattern = new 
var RegExp: RegExpConstructor
new (pattern: RegExp | string, flags?: string) => RegExp (+2 overloads)
RegExp("abc", 
const flags: string
flags);

Options

This rule is not configurable.

When Not To Use It

If you prefer to always use RegExp constructors for consistency, or if you are building patterns from static pieces that are easier to read as strings, you might prefer to disable this rule.

Equivalents in Other Linters

Biome: useRegexLiterals
ESLint: prefer-regex-literals

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regexLiterals

Examples

Options

When Not To Use It

Further Reading

Equivalents in Other Linters