use constepxr for NamedColors[]

Author: hjanetzek

csscolorparser.cpp

@@ -37,8 +37,9 @@
 using namespace CSSColorParser;
 
 // http://www.w3.org/TR/css3-color/
-struct NamedColor { const char *const name; const Color color; };
-const NamedColor namedColors[] = {
+struct NamedColor { const char *const name; const ConstColor color; };
+
+constexpr NamedColor namedColors[] = {
     { "aliceblue", { 240, 248, 255, 1 } },
     { "antiquewhite", { 250, 235, 215, 1 } },
     { "aqua", { 0, 255, 255, 1 } },

csscolorparser.hpp

@@ -28,9 +28,18 @@
 #include <string>
 
 namespace CSSColorParser {
+struct ConstColor {
+    constexpr inline ConstColor(unsigned char r, unsigned char g, unsigned char b, float a)
+        : r(r), g(g), b(b), a(a) {}
+    const unsigned char r = 0, g = 0, b = 0;
+    const float a = 1.0f;
+};
 
 struct Color {
     inline Color() {}
+    inline Color(const ConstColor& c)
+        : r(c.r), g(c.g), b(c.b), a(c.a) {}
+
     inline Color(unsigned char r, unsigned char g, unsigned char b, float a)
         : r(r), g(g), b(b), a(a) {}
     unsigned char r = 0, g = 0, b = 0;