use Perl

• Re: What We Can Learn From Other Languages (Score:1)

  by jmcnamara (659)

  I'm not sure if the first example is fair. Simple method overloading in Java or C++ is generally used for functions that can take different parameter types, which isn't an issue in Perl, or to have functions with optional parameters which again isn't much of a problem in Perl:

  sub someMethod {
      my $self = shift;
      my $foo  = shift || 1;
      ...
  }

  I think that method overloading is more tied to the fact the a language is statically typed and not necessarily something
  • Re: What We Can Learn From Other Languages (Score:2)

    by Ovid (2709) on 2007.03.01 6:00 (#53440) Homepage Journal

    Well, you say it's not much of a problem, but look at the snippet you posted:

    sub someMethod {
        my $self = shift;
        my $foo  = shift || 1;
        ...
    }

    Can $foo be 0? Your code says 'no', but that might or might not be what you meant. Also, by the time you've finished the $foo line, you no longer can easily tell whether or not you even passed an argument for $foo.

    In my original example, the code might do strange things if too many arguments are passed, or if they're not integers, even though that's what's expected. Params::Validate helps to mitigate many of these problems, but doesn't do anything for the multi-method dispatch bugs which can arise from sloppy programming (i.e., you dispatch to different methods based on the arguments or you have an ugly if/else construct). I've seen so many bugs arise from problems just with this.

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    • Re: (Score:1)

      by jmcnamara (659)

      When I said that it wasn't a problem I meant that it wasn't a problem to implement. Which isn't to say that there won't be problems in the implementation.
      
      Some of these problems could be solved efficaciously with method overloading. Nevertheless, I still think that method overloading is mainly a necessity of static typing. Which for me is a more useful language feature and one that we have learned from since it will be included in Perl 6.
      
      John.
      --