isWhitespace function

bool isWhitespace (int rune)

Returns true if rune represents a whitespace character.

The definition of whitespace matches that used in String.trim which is based on Unicode 6.2. This maybe be a different set of characters than the environment's RegExp definition for whitespace, which is given by the ECMAScript standard: http://ecma-international.org/ecma-262/5.1/#sec-15.10

Implementation 

bool isWhitespace(int rune) => ((rune >= 0x0009 && rune <= 0x000D) ||
    rune == 0x0020 ||
    rune == 0x0085 ||
    rune == 0x00A0 ||
    rune == 0x1680 ||
    rune == 0x180E ||
    (rune >= 0x2000 && rune <= 0x200A) ||
    rune == 0x2028 ||
    rune == 0x2029 ||
    rune == 0x202F ||
    rune == 0x205F ||
    rune == 0x3000 ||
    rune == 0xFEFF);