Don't allow ∞ with an exponent in numeric literals

1 files changed, 2 insertions, 2 deletions

diff --git a/spec/literal.md b/spec/literal.md
index 58e1b816..edf91b83 100644
--- a/spec/literal.md
+++ b/spec/literal.md
@@ -9,9 +9,9 @@ Two types of literal deal with text. As the source code is considered to be a se
 The format of a *numeric literal* is more complicated. From the [tokenization rules](token.md), a numeric literal consists of a numeric character (one of `¯∞π.0123456789`) followed by any number of numeric or alphabetic characters. Some numeric literals are *valid* and indicate a number, while others are invalid and cause an error. The grammar for valid numbers is given below in a [BNF](https://en.wikipedia.org/wiki/Backus%E2%80%93Naur_form) variant. Only four alphabetic characters are allowed: "i", which separates the real and imaginary components of a complex number, "e", which functions as in scientific notation, and the uppercase versions of these letters.
 
     number    = component ( ( "i" | "I" ) component )?
-    component = mantissa ( ( "e" | "E" ) exponent )?
+    component = "¯"? ( "∞" | mantissa ( ( "e" | "E" ) exponent )? )
     exponent  = "¯"? digit+
-    mantissa  = "¯"? ( "∞" | "π" | digit+ ( "." digit+ )? )
+    mantissa  = "π" | digit+ ( "." digit+ )?
     digit     = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
 
 The digits or arabic numerals correspond to the numbers from 0 to 9 in the conventional way (also, each corresponds to its code point value minus 48). A sequence of digits gives a natural number by evaluating it in base 10: the number is 0 for an empty sequence, and otherwise the last digit's numerical value plus ten times the number obtained from the remaining digits. The symbol `∞` indicates infinity and `π` indicates the ratio [pi](https://en.wikipedia.org/wiki/Pi_(mathematics)) of a circle's circumference to its diameter (or, for modern mathematicians, the smallest positive real number at which the function `{⋆0i1×𝕩}` attains a real part of 0). The [high minus](https://aplwiki.com/wiki/High_minus) symbol `¯` indicates that the number containing it is to be negated.