Programming languages: This old favourite is gaining popularity again (C#)

Re:Programming languages: This old favourite is gaining popu... by gnat on Tuesday December 07, 2021 @01:47PM (#29476554)

Not the only good feature, though. I've been doing Advent of Code in C# this year to get my head around it. The standard library and language features seem to be sane and nicely-designed and I am having fun with it.

As an aside, it's always interesting to see how standard libraries do splits and joins between arrays/tuples/collections and strings.

In Perl they're both functions:

  @arr = split(/ /, $str);
  $str = join (" ", @arr);

In Python they're methods on the separator or tuple:

  arr = str.split(" ")
  str = ",".join(tuple)

That idea that you're telling comma to join a group of items always rubbed me wrong. In C#, joining is a class method:

  arr = str.Split(" ");
  str = string.Join(" ", arr);

Here "string" is a class name. The lack of parallelism grates on me somewhat. I think I would have preferred

  str = arr.Join(" ");

Does anyone know why this form is not used?

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Re:Programming languages: This old favourite is gaining popu... by to11mtm on Tuesday December 07, 2021 @02:08PM (#29476833)

> Does anyone know why this form is not used?

Likely because early versions of C# (Pre-generics) wouldn't have had a good way to specifically offer a .Join method on string arrays specifically.

Now that we have generics, .Join() on an array normally refers to a type of Linq operation where you join two sequences together. You actually probably could make an extension method for your own usage in-app that would give you this functionality; if I had to guess why they didn't, I would assume it would consume Linq users.

OTOH that's kinda the nice thing about C# though. It's easy to go:

    public static class StringArrayExtensions
    {
        public static string Join(this string[] arr, string joinToken)
        {
           return string.Join(joinToken, arr);
        }
    }

and package such utility functions into a shared lib for your team to use.

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Re:Programming languages: This old favourite is gaining popu... by arun_m on Tuesday December 07, 2021 @05:10PM (#29478856)

There is a Join method in Linq, with entirely different meaning and matches string[]

https://docs.microsoft.com/en-us/dotnet/api/system.linq.enum...

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