On Wednesday, 29 January 2014 at 13:30:54 UTC, Martin Cejp wrote:
This is a feature I've always missed in C++. Consider the code
below:
import std.stdio;
interface Logger {
void print(string msg);
}
class ConsoleLogger : Logger {
static override void print(string msg) {
writeln(msg);
}
}
void main() {
Logger logger = new ConsoleLogger;
ConsoleLogger.print("Hello, World!");
}
I don't understand this code. You have a "logger" local variable,
but don't use it. Do you want the compiler to autodetect which
local variable to use by selecting one in the current scope?
Such definition of ConsoleLogger fails to compile. I don't see
any drawbacks to allowing this though, except the compiler would
probably have to generate 2 methods internally.
The way it is now, you have to either define each method twice
or
always create an instance.
Or am I missing an obvious solution?
What are you trying to accomplish?
You can use object instances as namespaces, too. Example:
/////////////////////////////////////////////////////////
import std.stdio;
interface Logger
{
void print(string msg);
}
class ConsoleLoggerImpl : Logger
{
override void print(string msg) const
{
writeln(msg);
}
}
const ConsoleLogger = new ConsoleLoggerImpl;
void main()
{
ConsoleLogger.print("Hello, World!");
}
/////////////////////////////////////////////////////////
Note that ConsoleLogger is "instantiated" at compile time, not
runtime. To instantiate it at runtime, during initialization, you
can use a static constructor.
