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digitalmars.D.learn - What is iota function full name

reply lili <akozhao tencent.com> writes:
Hi Guys：
     What is range.iota function full name
Jun 21 2019
next sibling parent reply aliak <something something.com> writes:
On Friday, 21 June 2019 at 09:01:17 UTC, lili wrote:

 Hi Guys：
     What is range.iota function full name


That is the full name. Or what do you mean?

Found on the internet somewhere:

"The function is named after the integer function ⍳ from the 
programming language APL."
Jun 21 2019
parent reply lili <akozhao tencent.com> writes:
On Friday, 21 June 2019 at 09:09:33 UTC, aliak wrote:

 On Friday, 21 June 2019 at 09:01:17 UTC, lili wrote:

 Hi Guys：
     What is range.iota function full name


 That is the full name. Or what do you mean?

 Found on the internet somewhere:

 "The function is named after the integer function ⍳ from the 
 programming language APL."


😄 I mean is that the what is iota stands for.

in dictionary iota means:
a tiny or scarcely detectable amount
the 9th letter of the Greek alphabet
  but this function is not that mean.
Jun 21 2019
parent Andrea Fontana <nospam example.com> writes:
On Friday, 21 June 2019 at 09:24:54 UTC, lili wrote:

 in dictionary iota means:
 a tiny or scarcely detectable amount
 the 9th letter of the Greek alphabet
  but this function is not that mean.


Full answer:
https://stackoverflow.com/questions/9244879/what-does-iota-of-stdiota-stand-for
Jun 21 2019
prev sibling parent reply Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:
On Friday, June 21, 2019 3:01:17 AM MDT lili via Digitalmars-d-learn wrote:

 Hi Guys：
      What is range.iota function full name


iota _is_ its full name. It's named after an STL function which does
basically the same with iterators in C++:

https://en.cppreference.com/w/cpp/algorithm/iota

Apparently, C++ got it from the APL programming language, which uses Greek
characters and other symbols that you can't find on most keyboards, which
makes APL code more like what you see in equations in a math textbook, and
APL uses the Greek letter iota for a function with similar behavior to the
C++ and D functions. And since unlike APL, C++ couldn't use the Greek
letter, when they named their version of the function, they used the name of
the letter rather than the letter. And then D's function name was named
after the C++ function. So, iota is the name of the function, and it doesn't
stand for anything. It's just the name of the Greek letter that was used for
a similar function in another language that most programmers these days have
probably never heard of.

- Jonathan M Davis
Jun 21 2019
next sibling parent KlausO <oberhofer users.sf.net> writes:
So basically iota spills Increments Over The Array.

Am 21.06.2019 um 11:18 schrieb Jonathan M Davis:

 On Friday, June 21, 2019 3:01:17 AM MDT lili via Digitalmars-d-learn wrote:

 Hi Guys：
       What is range.iota function full name


 
 iota _is_ its full name. It's named after an STL function which does
 basically the same with iterators in C++:
 
 https://en.cppreference.com/w/cpp/algorithm/iota
 
 Apparently, C++ got it from the APL programming language, which uses Greek
 characters and other symbols that you can't find on most keyboards, which
 makes APL code more like what you see in equations in a math textbook, and
 APL uses the Greek letter iota for a function with similar behavior to the
 C++ and D functions. And since unlike APL, C++ couldn't use the Greek
 letter, when they named their version of the function, they used the name of
 the letter rather than the letter. And then D's function name was named
 after the C++ function. So, iota is the name of the function, and it doesn't
 stand for anything. It's just the name of the Greek letter that was used for
 a similar function in another language that most programmers these days have
 probably never heard of.
 
 - Jonathan M Davis
Jun 21 2019
prev sibling parent reply JN <666total wp.pl> writes:
On Friday, 21 June 2019 at 09:18:49 UTC, Jonathan M Davis wrote:
So, iota is

 the name of the function, and it doesn't stand for anything. 
 It's just the name of the Greek letter that was used for a 
 similar function in another language that most programmers 
 these days have probably never heard of.

 - Jonathan M Davis


I don't even understand why get so much inspiration from C++. Why 
not just name it seq or sequence?
Jun 21 2019
parent reply Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:
On Friday, June 21, 2019 5:10:03 AM MDT JN via Digitalmars-d-learn wrote:

 On Friday, 21 June 2019 at 09:18:49 UTC, Jonathan M Davis wrote:
 So, iota is


 the name of the function, and it doesn't stand for anything.
 It's just the name of the Greek letter that was used for a
 similar function in another language that most programmers
 these days have probably never heard of.

 - Jonathan M Davis


 I don't even understand why get so much inspiration from C++. Why
 not just name it seq or sequence?


Quite a lot of the functions in std.algorithm (especially the functions that
it got early on) are modeled after similar functions in C++, standard
library, and when Andrei wrote those functions, he purposefully made them
use the same names as they have in C++. For anyone already familiar with
those functions in C++ (including iota), having the same names makes sense.
Other people are more likely to look at the names on their own merits, and
as such, the names don't necessarily make as much sense (particularly iota).
Regardless, given that Andrei was heavily involved in C++ long before he got
involved with D, it's not exactly surprising that he'd use the C++ names
rather than coming up with new ones - especially when std.algorithm was
originally heavily modeled after C++'s algorithm header.

Some folks argued a while back that iota was a terrible name and that it
should be changed, but it was decided not to change it. However, truth be
told, if you know what iota is, the name is more descriptive than a more
generic name like sequence or generateRange would be. It's just a terrible
name from the perspective that it's not at all decriptive of what it is.
It's just a name that has historically been used for this particular
operation.

In practice, what tends to happen is that when someone first encounters
iota, they think that it's a terrible name, but in the long run, they just
know what it is, and it isn't actually a problem. Either way, at this point,
names in Phobos don't get changed just because some folks think that a name
isn't as good as it could be or should be, because changing would break
code, and Walter and Andrei do not believe that simply giving something a
better name is worth breaking anyone's code.

- Jonathan M Davis
Jun 21 2019
parent reply KnightMare <black80 bk.ru> writes:
On Friday, 21 June 2019 at 12:02:10 UTC, Jonathan M Davis wrote:

 On Friday, June 21, 2019 5:10:03 AM MDT JN via



 Some folks argued a while back that iota was a terrible name 
 and that it should be changed, but it was decided not to change 
 it.


auto terribleName( ... ) { }

auto goodName( ... ) {
     pragma( inline, true )
     return terribleName( ... );
}

everyone is happy
Jun 21 2019
next sibling parent Marco de Wild <mdwild sogyo.nl> writes:
On Friday, 21 June 2019 at 19:18:02 UTC, KnightMare wrote:

 On Friday, 21 June 2019 at 12:02:10 UTC, Jonathan M Davis wrote:

 On Friday, June 21, 2019 5:10:03 AM MDT JN via



 Some folks argued a while back that iota was a terrible name 
 and that it should be changed, but it was decided not to 
 change it.


 auto terribleName( ... ) { }

 auto goodName( ... ) {
     pragma( inline, true )
     return terribleName( ... );
 }

 everyone is happy


Good tip. I usually make a file for these kind of aliases and 
simple functions that do not end up in the standard library, eg 
std.algorithm oneliners.
Jun 21 2019
prev sibling parent reply KnightMare <black80 bk.ru> writes:
On Friday, 21 June 2019 at 19:18:02 UTC, KnightMare wrote:

 On Friday, 21 June 2019 at 12:02:10 UTC, Jonathan M Davis wrote:



 auto goodName( ... ) {
     pragma( inline, true )
     return terribleName( ... );
 }


hmm.. I have a question: this pragma will inline terribleName 
(double code) or goodName (fine)?
Jun 21 2019
parent Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:
On Friday, June 21, 2019 3:31:46 PM MDT KnightMare via Digitalmars-d-learn 
wrote:

 On Friday, 21 June 2019 at 19:18:02 UTC, KnightMare wrote:

 On Friday, 21 June 2019 at 12:02:10 UTC, Jonathan M Davis wrote:

 auto goodName( ... ) {

     pragma( inline, true )
     return terribleName( ... );

 }


 hmm.. I have a question: this pragma will inline terribleName
 (double code) or goodName (fine)?


pragma(inline, true) goes on function declarations, not on function calls.
So, you would need to put it on goodName's signature, in which case, it's
goodName which would be inlined. There is no way for a caller to force a
function to be inlined.

- Jonathan M Davis
Jun 21 2019