parse nan, inf

Author: kaushikcfd

pymbolic/parser.py

@@ -144,6 +144,8 @@ class Parser:
                     r"[0-9]*\.[0-9]+[eEdD][+-]?[0-9]+([a-zA-Z]*)\b"),
                 # has a letter tag
                 pytools.lex.RE(r"[0-9]+([a-zA-Z]+)"),
+                # inf, nan
+                pytools.lex.RE("inf"), pytools.lex.RE("nan"),
                 )),
             (_int, pytools.lex.RE(r"[0-9]+")),
 
@@ -181,6 +183,14 @@ class Parser:
             }
 
     def parse_float(self, s):
+        if s == "inf":
+            from math import inf
+            return inf
+
+        if s == "nan":
+            from math import nan
+            return nan
+
         return float(s.replace("d", "e").replace("D", "e"))
 
     def parse_terminal(self, pstate):