ConfigParser: AsPath

It look line there is no c# library to expand linux style env variable in path.
Let's write it  myself!

ConfigParser.cs

@@ -180,6 +180,38 @@ class ConfigValue
 		if(Value == null) throw new ConfigNoValueException(this);
 		return Value;
 	}
+	public string AsPath()
+	{
+		string s = AsString();
+		StringBuilder output = new();
+		for(int i=0;i<s.Length;i++)
+		{
+			if(i == 0 && s[i]=='~')
+			{
+				output.Append(Environment.GetEnvironmentVariable("HOME") ?? "");
+			}
+			else  if(s[i]=='$')
+			{
+				int start, end;
+				if(s[i+1]=='{')
+				{
+					start = i+2;
+					while(i<s.Length && s[i]!='}') i++;
+					end = i;
+				}
+				else
+				{
+					start = i+1;
+					while(i+1<s.Length && "qwertyuiopasdfghjklzxcvbnm1234567890QWERTYUIOPASDFGHJKLZXCVBNM_".Contains(s[i+1])) i++;
+					end = i+1;
+				}
+				output.Append(Environment.GetEnvironmentVariable(s[start..end]) ?? "");
+			}
+			else
+				output.Append(s[i]);
+		}
+		return output.ToString();
+	}
 	public Color AsColor()
 	{
 		try