dyaml/examples/constructor/main.d
2014-08-01 17:09:05 +02:00

102 lines
2.4 KiB
D

import std.stdio;
import std.string;
import dyaml.all;
struct Color
{
ubyte red;
ubyte green;
ubyte blue;
const int opCmp(ref const Color c)
{
if(red != c.red) {return red - c.red;}
if(green != c.green){return green - c.green;}
if(blue != c.blue) {return blue - c.blue;}
return 0;
}
}
Color constructColorScalar(ref Node node)
{
string value = node.as!string;
if(value.length != 6)
{
throw new Exception("Invalid color: " ~ value);
}
//We don't need to check for uppercase chars this way.
value = value.toLower();
//Get value of a hex digit.
uint hex(char c)
{
import std.ascii;
if(!std.ascii.isHexDigit(c))
{
throw new Exception("Invalid color: " ~ value);
}
if(std.ascii.isDigit(c))
{
return c - '0';
}
return c - 'a' + 10;
}
Color result;
result.red = cast(ubyte)(16 * hex(value[0]) + hex(value[1]));
result.green = cast(ubyte)(16 * hex(value[2]) + hex(value[3]));
result.blue = cast(ubyte)(16 * hex(value[4]) + hex(value[5]));
return result;
}
Color constructColorMapping(ref Node node)
{
ubyte r,g,b;
//Might throw if a value is missing is not an integer, or is out of range.
//If this happens, D:YAML will handle the exception and use its message
//in a YAMLException thrown when loading.
r = node["r"].as!ubyte;
g = node["g"].as!ubyte;
b = node["b"].as!ubyte;
return Color(cast(ubyte)r, cast(ubyte)g, cast(ubyte)b);
}
void main()
{
auto red = Color(255, 0, 0);
auto orange = Color(255, 255, 0);
try
{
auto constructor = new Constructor;
//both functions handle the same tag, but one handles scalar, one mapping.
constructor.addConstructorScalar("!color", &constructColorScalar);
constructor.addConstructorMapping("!color-mapping", &constructColorMapping);
auto loader = Loader("input.yaml");
loader.constructor = constructor;
auto root = loader.load();
if(root["scalar-red"].as!Color == red &&
root["mapping-red"].as!Color == red &&
root["scalar-orange"].as!Color == orange &&
root["mapping-orange"].as!Color == orange)
{
writeln("SUCCESS");
return;
}
}
catch(YAMLException e)
{
writeln(e.msg);
}
writeln("FAILURE");
}