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by ansin 6281 days ago

"I don't see where Ruby syntax is particularly more concise than C# 3's."

1.upto(10).each{|x| print x}

I'm curious - how would you print 1 through 10 in C# 3 by comparison?

5 comments

namelessmike 6281 days ago

C# 3:

  (1).UpTo(10).ForEach(x => Console.WriteLine(x));

Of course, "UpTo" requires first extending int, which is trivial:

  public static class IntExtensions {
      public static List<int> UpTo(this int start, int end) {
          var range = new List<int>();
          for(int i = start; i < end; i++) {
              range.Add(i);
          }
          return range;
      }
  }

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_pius 6281 days ago

That's cool and all, but I think being able to do this natively in Ruby wins:

  p *1..10

Edit: you may need to do a "require 'pp'" first.

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ankhmoop 6281 days ago

One way to do this in Scala:

  def print[T] (value:T) = System.out.println(value)
  1.until(10).foreach(x => print x)

This is a fairly uninteresting example, however. Something more interesting would be, for instance, the use of structural types to implement type-checked duck typing.

Scala example:

  // Declare a structural type for any class implementing close()
  type Closable = {def close(): Any}
  
  // Executes the provided function with the given
  // closable generator, creating a new instance which
  // will then be closed on completion. The provided
  // function's value will be returned.
  def withClosable[T, C <: Closable] (c: => C) (f: (C) => T) = {
    val closable = c
    try {
      f(closable)
    } finally {
      closable.close
    }
  }
  
  // Example usage
  def usage = {
    val updated = withClosable(db.openConnection) { conn =>
      conn.update("INSERT INTO example VALUES (...")
    }
    System.out.println("Rows updated: " + updated)
  }

This could be compared with Python's new 'with' syntax.

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henning 6281 days ago

Since there's plenty of shitting on Scala going on, I'd like to point out that the Scala equivalent of that is: