Re: Type conversion for hundreds of lines

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From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups	comp.lang.c++
Subject	Re: Type conversion for hundreds of lines
Date	Thu, 13 Oct 2022 12:19:42 +0100
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JiiPee <kerrttuPoistaTama11@gmail.com> writes:

> On 13/10/2022 01:26, Ben Bacarisse wrote:
>> ... and presumably you meant sum += v[i]; or the loop is pointless!
>> And why run the indexes backwards?  It might be needed for some vectors
>> of floating-point numbers, but not for int.
>> It seems that a lot of peculiar choices have been made in the code base.
>
> the example is only created to illustrate the copy propblem... its not
> an example from a real code.

Sure, but the loop running backwards, starting at size-1, introduces other
things to be careful about.

> The point is, that if I copy in a for-loop vector::size() to an
> integer, do you always do the casting for it?

No.  Since the scope is small in a for loop, I'd change the declaration
and run the loop forward.  It's more changes, but it will make the code
clearer.

If I had reliable regression tests, I'd consider writing

  int sum = std::accumulate(v.begin(), v.end(), 0);

> Because there are many places that can happen....

Roughly how many?  I think it makes sense to tidy up the code rather
than spray it with casts.

-- 
Ben.

Thread

Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-12 23:48 +0300
  Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-12 23:54 +0300
    Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-12 23:55 +0300
      Re: Type conversion for hundreds of lines Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-10-12 23:26 +0100
        Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:30 +0300
          Re: Type conversion for hundreds of lines Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-10-13 12:19 +0100
    Re: Type conversion for hundreds of lines Paavo Helde <eesnimi@osa.pri.ee> - 2022-10-13 00:37 +0300
      Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:34 +0300
        Re: Type conversion for hundreds of lines Paavo Helde <eesnimi@osa.pri.ee> - 2022-10-13 11:43 +0300
  Re: Type conversion for hundreds of lines Paavo Helde <eesnimi@osa.pri.ee> - 2022-10-13 00:27 +0300
    Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:24 +0300
      Re: Type conversion for hundreds of lines Paavo Helde <eesnimi@osa.pri.ee> - 2022-10-13 12:00 +0300
        Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 20:27 +0300
      Re: Type conversion for hundreds of lines David Brown <david.brown@hesbynett.no> - 2022-10-13 11:17 +0200
        Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 20:32 +0300
          Re: Type conversion for hundreds of lines Paavo Helde <eesnimi@osa.pri.ee> - 2022-10-13 21:13 +0300
            Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 21:28 +0300
          Re: Type conversion for hundreds of lines David Brown <david.brown@hesbynett.no> - 2022-10-13 23:10 +0200
          Re: Type conversion for hundreds of lines Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2022-10-13 22:36 +0100
            Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-14 07:29 +0300
  Re: Type conversion for hundreds of lines scott@slp53.sl.home (Scott Lurndal) - 2022-10-12 21:27 +0000
    Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:25 +0300
  Re: Type conversion for hundreds of lines Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-10-12 14:30 -0700
    Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:28 +0300
      Re: Type conversion for hundreds of lines "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-10-12 21:30 -0700
        Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 07:37 +0300
          Re: Type conversion for hundreds of lines "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-10-13 14:18 -0700
            Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-14 00:27 +0300
              Re: Type conversion for hundreds of lines "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-10-14 00:33 -0700
  Re: Type conversion for hundreds of lines Juha Nieminen <nospam@thanks.invalid> - 2022-10-13 07:52 +0000
    Re: Type conversion for hundreds of lines JiiPee <kerrttuPoistaTama11@gmail.com> - 2022-10-13 20:35 +0300
  Re: Type conversion for hundreds of lines Frederick Virchanza Gotham <cauldwell.thomas@gmail.com> - 2022-10-14 01:43 -0700

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