CLCS

Escape Characters and Potential Numbers

A potential number cannot contain any escape characters. An escape character robs the following character of all syntactic qualities, forcing it to be strictly alphabetic_2 and therefore unsuitable for use in a potential number. For example, all of the following representations are interpreted as symbols, not numbers:

 \256   25\64   1.0\E6   |100|   3\.14159   |3/4|   3\/4   5||

In each case, removing the escape character (or characters) would cause the token to be a potential number.