I recently briefly checked some Julia books such as,
Anyway, this book again reminds me that, believe it or not, Julia and Fortran are more or less competing in some way, and it is happening, with or without you and me. Fortran is very good, but perhaps need to absorb some good ideas from other language as quick as possible.
For example, in Julia, there is something called Namespace. So one can define, eg, the same name of variable/function/subroutine called func in both module AAA and BBB. When use func, one just need to do module_name.func like below,
I know in Fortran there is no such thing, but can do some => aliasing trick,
But the idea of Namespace seems to be very convenient and useful.
Just curious, is there plan that this feature could be added to Fortran in the nearest future?
As @plevold said, that is literally the issue number 1 in our proposal list, as it was the first thing people suggested to me Fortran should have. As you can see, it is upvoted a lot. @CRquantum and others if you like it, please upvote it as well.
The use of a new keyword/statement seems promising. Earlier discussions seemed to focus more on possible additions to the existing use statement, but all seemed a bit more clumsy. Note that the use of . as the separator is probably troublesome due to the existing user defined operator semantics (i.e. something.dot.otherthing). I’ve seen some suggestions that maybe it’s still workable, but it’s probably easy enough to pick a different symbol/ligature; -> perhaps?
I don’t think that’s a problem, and I think there are already situations allowed by the standard where such aliasing can occur. However, the onus is on the programmer not to alias actual arguments through dummy arguments. I.e.
use mod, only: b => a
use mod, only: c => a
call swap(b, c)
is technically not standards conforming, but compilers are not required to (and in many instances can’t) check for it.
We just used the @ symbol for rank agnostic array section denotation (or something like that). It’s coming in the next standard. I’m not quite clear whether that would preclude it’s use for this purpose though.
Maybe? I believe that the current standard is limited to the original ASCII character set, of which ~ is not a member. But I may be incorrect on either of those, and it may be possible to expand that set. It would require a bit of background research.
@everythingfunctional , do you mean the original Fortran character set or the original ASCII (ISO 646) character set. Tilde is part of ISO 646 but is one of those characters that are reserved for “national use” which means its ASCII value (126) might be a different symbol in other countries. I doubt that the standard is restricted to the original Fortran character set since the square bracket [ is not included in that character set.
I’m honestly not clear on the details. It was more just a vague recollection of something I heard when discussing the use of the @ symbol for a feature in the upcoming standard. I thought I heard somebody say we were running out of available symbols, and listed off the ones we hadn’t used. I don’t believe ~ was among them. If somebody wants to investigate what exactly is available in the Fortran character set and what symbols are left unused I would be interested to hear it.