ECMAScript® 2024 Language Specification

Draft ECMA-262 / December 6, 2023

12.2 White Space

White space code points are used to improve source text readability and to separate tokens (indivisible lexical units) from each other, but are otherwise insignificant. White space code points may occur between any two tokens and at the start or end of input. White space code points may occur within a StringLiteral, a RegularExpressionLiteral, a Template, or a TemplateSubstitutionTail where they are considered significant code points forming part of a literal value. They may also occur within a Comment, but cannot appear within any other kind of token.

The ECMAScript white space code points are listed in Table 36.

Table 36: White Space Code Points
Code Points Name Abbreviation
U+0009 CHARACTER TABULATION <TAB>
U+000B LINE TABULATION <VT>
U+000C FORM FEED (FF) <FF>
U+FEFF ZERO WIDTH NO-BREAK SPACE <ZWNBSP>
any code point in general category “Space_Separator” <USP>
Note 1

U+0020 (SPACE) and U+00A0 (NO-BREAK SPACE) code points are part of <USP>.

Note 2

Other than for the code points listed in Table 36, ECMAScript WhiteSpace intentionally excludes all code points that have the Unicode “White_Space” property but which are not classified in general category “Space_Separator” (“Zs”).

Syntax

WhiteSpace :: <TAB> <VT> <FF> <ZWNBSP> <USP>