prefer-numeric-literals.md

Pattern: Use of parseInt for numeric literals

Issue: -

Description

ES6 supports binary, octal, and hexadecimal literals, making parseInt() and Number.parseInt() unnecessary for converting string representations of these numbers. Using numeric literals directly is more concise and clearer.

Examples

Example of incorrect code:

parseInt("111110111", 2);
parseInt("767", 8);
parseInt("1F7", 16);

Number.parseInt("111110111", 2);
Number.parseInt("0767", 8);
Number.parseInt("1F7", 16);

parseInt(`111110111`, 2);
parseInt("0xFF", 16);

Example of correct code:

0b111110111;   // binary
0o767;         // octal
0x1F7;         // hexadecimal

// ParseInt is ok for non-literal strings
parseInt(someVariable, 10);
Number.parseInt(value, 2);

// Parsing strings that aren't literals
parseInt("12.5", 10);
Number.parseInt(getUserInput(), 16);