Beefy Boxes and Bandwidth Generously Provided by pair Networks
Clear questions and runnable code
get the best and fastest answer
 
PerlMonks  

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
Consider this:

I have two classes: Logger::Local and Logger::Remote. Each of them implements log method in a different way. One appends message to local file, the other send a message to remote server. I want these two classes to have the same interface, so I create abstract superclass Logger that will define such an interface. This superclass also provides some common methods (for example method instance).

In your scenario call to Logger::Local->instance may return instance of Logger::Remote class, which is aparently not desired here. The class returned is not even superclass nor subclass of Logger::Local and the interface could not match. The fact that Perl is not typed language and does not enforce interface checks like Java does does not mean that all OO good practice should be abandoned.

Better way is to have such instance method that allways returns instance of class that it has been called upon. And when some 'class agregation' is desired, it should be done explicitly be overriding this method.


In reply to Re: Re: Re: Re: Ruby: An Abbot breaks silencewind by gildir
in thread Ruby: An Abbot breaks silencewind by coreolyn

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others avoiding work at the Monastery: (3)
As of 2021-12-09 14:51 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    R or B?



    Results (36 votes). Check out past polls.

    Notices?