Welcome to the fifth post about the Kephra Base Object System, where I explain the need for three kinds of attributes: data, delegating and wrapping and gas a little about their properties. It is especially advised to have read the first part (scopes) and the previous part, since accessors are methods.

In case you wonder how practical this exercise is - I already implemented a slightly simpler version and currently rewrite it. It's a standalone bundle of modules with its own tests and docs named Base-Class (Kephra::Base::Class) (123kB), which depends only on the bundle Base (there are the data types) (32 kB). So once ready it could be released on CPAN without much work.

After scopes, types and signatures we got all the prerequisites to talk about the syntax and semantics of KBOS methods. Unless you want to contribute to Kephra or write a plugin, you may never use them, but please join me in the thought experiment - maybe we get a littler smarter.

There are signatures in Raku, core Perl 5, Moose, Dios and lot of other modules. With KBOS I tried to find out how optimal signatures would look like to me. My objectives are: 3. easy to parse with the eye, 2. concise syntax and 1. delegates as much work as possible into the background so I have to write the least amount of code.

After introducing KBOS I should write about the most fundamental concept in this Perl syntax extension. In fact it's so basic, you could use it even without objects.

Starting even before Moose, we (in the Perl 5 world) have a plethora of Modules extending the syntax of the language with Perl 6 and more in mind. The following article sums up not only my 2 and a half cents on the subject but also an attempt to implement it. It should be of interest to anybody thinking about programming in general.