GH-68 Fix p4StrNum() should not parse "E" as a float.

Author: SirWumpus

src/post4.c

@@ -258,7 +258,8 @@ p4StrNum(P4_String str, int base, P4_Cell *out, int *is_float)
 			/* We don't accept the double-cell notation 123. 0.
 			 * as this is confusing with floating point input.
 			 */
-			if (str.string[offset] == '.' || toupper(str.string[offset]) == 'E') {
+			if (str.string[offset] == '.'
+			|| (0 < offset && isdigit(str.string[offset-1]) && toupper(str.string[offset]) == 'E')) {
 				if (base != 10) {
 					return -1;
 				}

test/float.p4

@@ -6,6 +6,10 @@ INCLUDE ../test/assert.p4
 
 [ELSE]
 
+.( GH-68 e is not a float ) test_group
+t{ s" 0 0 efoobar-undefined-word" ' evaluate catch nip nip -> -13 }t
+test_group_end
+
 .( F0= ) test_group
 t{  0.0 F0= -> TRUE }t
 t{  1.0 F0= -> FALSE }t