ANSI Common Lisp   2 Syntax   2.3 Interpretation of Tokens

2.3.1 Numbers as Tokens

Syntax For Numeric Tokens

numeric-token ::= integer | ratio | float integer ::= [sign] {decimal-digit}+ decimal-point | [sign] {digit}+ ratio ::= [sign] {digit}+ slash {digit}+ float ::= [sign] {decimal-digit}* decimal-point {decimal-digit}+ [exponent]| [sign] {decimal-digit}+ [decimal-point {decimal-digit}*] exponent exponent ::= exponent-marker [sign] {digit}+ sign---a sign. slash---a slash decimal-point---a dot. exponent-marker---an exponent marker. decimal-digit---a digit in radix 10. digit---a digit in the current input radix.

2.3.1.1  Potential Numbers as Tokens