Executing a D script without an [extension in the filename] leads to an error

[Seb]

On Friday, 1 March 2019 at 11:38:51 UTC, BoQsc wrote:
> On Friday, 1 March 2019 at 09:27:33 UTC, Cym13 wrote:
>> On Friday, 1 March 2019 at 09:00:43 UTC, BoQsc wrote:
>>> [...]
>>
>> In such questions it's important to show your shebang since 
>> that's what runs your script.
>>
>> Given your symptoms I guess you're using the following:
>>
>> #!/bin/env rdmd
>>
>> And indeed rdmd won't call your script if it doesn't have the 
>> proper extension.
>>
>> Try using this instead:
>>
>> #!/bin/dmd -run
>
> The shebang I used: #!/usr/bin/env rdmd
>
> I was visiting Dlang Tour and that's where I've got an example 
> of shebang usage, directly from there:
> https://tour.dlang.org/tour/en/welcome/run-d-program-locally#/on-the-fly-compilation-with-rdmd
>
> The shebang you suggested actually works perfectly:
> #!/bin/dmd -run
>
>
> "And indeed rdmd won't call your script if it doesn't have the 
> proper extension."
>
> Then why does Dlang Tour includes shebang: #!/usr/bin/env rdmd
>
> Instead of the one you mentioned, that is fool proof. 
> (#!/bin/dmd -run)
>
> Is that an error/mistake in Dlang Tour guide?

Well, because it isn't fool proof either ;-)

It won't work once you start using more files as you would then 
need the -i flag , but unfortunately most systems don't support 
more than one shebang argument.

I think it's simply a missing feature of rdmd to accept files 
without an extension as D programs (though of course the tour 
could be improved to be more explanatory here too).