What have you done with UDAs?

[Dmitry Olshansky via Digitalmars-d]

On 22-Jun-2015 22:21, Alex Parrill wrote:
> On Monday, 22 June 2015 at 19:09:40 UTC, weaselcat wrote:
>> I never seem to use them for anything, has anyone else done anything
>> interesting with them?
>
> I'm writing a program that can accept subcommands via either the command
> line (ex. `prog mycmd 1 2`) or via a shell. I represent each command as
> a function, use UDAs to store the help text and if they can be ran from
> the command line or shell. The command list, full help text, and command
> dispatcher is generated at compile time via templates, CTFE, and static
> foreach.

And I thought that I might be the only one doing this ;)
Declarative command-line handling is much more scalable approach for 
swiss-army knife command-line tools.

> An example command:
>
> @("<nanoseconds>") // arguments
> @("Sets the amount of time to increment the clock on each frame.") //
> description
> @ShellOnly // can't be ran from command line
> int cmd_set_time_per_frame(string[] args) {
>      // ...
> }

Awesome. Is it open-sourced?
How about handling argument conversion automatically (via to! and/or 
custom functions)?

Say :
@("<num1> <num2>")
@CmdName("plus")
void add(int a, int b)
{
	writelen(a+b);
}


To be automagically callable like:

./prog plus 2 4


-- 
Dmitry Olshansky