(parse|test) (inf|nan)

Author: kaushikcfd

pymbolic/parser.py

@@ -37,6 +37,8 @@
 _closepar = intern("closepar")
 _openbracket = intern("openbracket")
 _closebracket = intern("closebracket")
+_inf = intern("inf")
+_nan = intern("nan")
 _identifier = intern("identifier")
 _whitespace = intern("whitespace")
 _comma = intern("comma")
@@ -164,6 +166,8 @@ class Parser:
             (_closepar, pytools.lex.RE(r"\)")),
             (_openbracket, pytools.lex.RE(r"\[")),
             (_closebracket, pytools.lex.RE(r"\]")),
+            (_inf, pytools.lex.RE(r"inf")),
+            (_nan, pytools.lex.RE(r"nan")),
             (_identifier, pytools.lex.RE(r"[@$a-z_A-Z_][@$a-zA-Z_0-9]*")),
             (_whitespace, pytools.lex.RE("[ \n\t]*")),
             (_comma, pytools.lex.RE(",")),
@@ -193,6 +197,14 @@ def parse_terminal(self, pstate):
             return self.parse_float(pstate.next_str_and_advance())
         elif next_tag is _imaginary:
             return complex(pstate.next_str_and_advance())
+        elif next_tag is _inf:
+            from math import inf
+            assert pstate.next_str_and_advance() == "inf"
+            return inf
+        elif next_tag is _nan:
+            from math import nan
+            assert pstate.next_str_and_advance() == "nan"
+            return nan
         elif next_tag is _identifier:
             return primitives.Variable(pstate.next_str_and_advance())
         elif next_tag is _if:

test/test_pymbolic.py

@@ -290,6 +290,10 @@ def test_parser():
     with pytest.deprecated_call():
         parse("1+if(0, 1, 2)")
 
+    import math
+    assert math.isinf(parse("inf"))
+    assert math.isnan(parse("nan"))
+
 # }}}