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From: "Fuschia, President-Elect of the Bright Purplish-Green Council" <fp-eotbp-gc@ibm.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Passing a Method Name to a Method
Date: Thu, 23 Jun 2011 15:46:16 -0400
Organization: IBM
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On 23/06/2011 2:32 PM, markspace wrote:
> On 6/23/2011 10:42 AM, Fuschia, President-Elect of the Bright
>>
>> I'll just mention here that functional programming, in this case at
>> least, also gives the advantages given by object oriented programming;
>> specifically, you can add another parse method by adding another (third)
>> parse *function* without changing most of the other code. And generally
>
> I'll just mention here that this is fairly specious.

Wrong.

> A proper OO solution, like the ones I gave, you can add another parser
> just by adding the appropriate class. The boiler plate is about two lines.

1. package foo;
2.
3. import bar.baz.ParseStrategy;
4.
5. public final class MyParseStrategy implements ParseStrategy {
6.     public final Thingy parse (String input) {
7.         // The actual implementation goes here
8.     }
9. }

I count 8 lines of non-implementation code, not 2, and 162 characters, 
plus eight "extra" characters per line of implementation code to indent 
it properly. Versus this Clojure code:

(defn my-parse [input]
   (the actual implementation goes here))

ONE line of non-implementation code and 26 characters, plus two indent 
spaces per line of implementation code.

1/8 as many lines. 1/6 as many characters. 1/4 as many indent spaces per 
line of implementation code. And probably a shorter & sweeter 
implementation as well.

> The interface is already done, skeleton, imports, etc are already done.
> Just add a class with a method. What you gain in Java is type safety,
> something not available in the "functional" languages I'm familiar with.

Scala also gets you type safety, at a cost of a bit more boilerplate 
than the Clojure example.