Some additional checks for the MacOS workaround for Issue beltoforion…

…#116

parser/mpValReader.cpp

@@ -68,28 +68,32 @@ bool DblValReader::IsValue(const char_type* a_szExpr, int& a_iPos, Value& a_Val)
 	if (stream.fail())
 	{
 #ifdef __APPLE__
-		// Workaround for clang not parsing strings like 3i with std::stringstream(imaginary numbers)
+		// Workaround for MacOS/clang not parsing strings like 3i with std::stringstream
 		// See https://discourse.llvm.org/t/different-behavior-from-stringstream-operator-in-libc-vs-libstdc/57482
-		// yields 3 groups if successful. The 2nd and 3rd groups when present together as in 3i or 2n is what
-		// clang does differently compared to gcc and visual studio
-		//			1	2	   3
+		// The regexp yields 3 groups if successful. The 2nd and 3rd groups when present together as in
+		// 3i or 2n is what clang does differently compared to gcc and visual studio
+		// GROUP:	       1	2	   3
 		std::regex pattern("(\\s*)(\\d+\\.*\\d*)(\\w+).*");
 		std::smatch match;
-		std::string str(a_szExpr+ a_iPos);
+		std::string str(a_szExpr + a_iPos);
 		if (std::regex_match(str, match, pattern) && match.size() == 4 && match[3].length() == 1)
 		{
-			float_type fVal = std::stof(match[2]);
-			bool is_imaginary = match[3] == "i";
-			if (is_imaginary)
+			stringstream_type stream(match[2]);
+			stream >> fVal;
+			if (!stream.fail())
 			{
-				a_Val = cmplx_type(0.0, fVal);
-			}
-			else
-			{
-				a_Val = cmplx_type(fVal, 0.0);
+				bool is_imaginary = (match[3] == "i");
+				if (is_imaginary)
+				{
+					a_Val = cmplx_type(0.0, fVal);
+				}
+				else
+				{
+					a_Val = cmplx_type(fVal, 0.0);
+				}
+				a_iPos += match[1].length()+match[2].length()+(is_imaginary?1:0);
+				return true;
 			}
-			a_iPos += match[1].length()+match[2].length()+(is_imaginary?1:0);
-			return true;
 		}
 #endif
 		return false;