2.1.135 [ECMA-262-1999] Section 15.10.2.15, NonemptyClassRanges

V0200:

The internal helper function CharacterRange takes two CharSet parameters A and B and performs the following:

1. If A does not contain exactly one character or B does not contain exactly one character then throw a #SyntaxError# __RegExpError__ exception.

2. Let a be the one character in CharSet A.

3. Let b be the one character in CharSet B.

4. Let i be the code point value of character a.

5. Let j be the code point value of character b.

6. If i > j then throw a #SyntaxError# __RegExpError__ exception.

7. Return the set containing all characters numbered i through j, inclusive.