I did some research on methods in enums and discovered that there is some usefulness to the idea - I wouldn't go so far as to say that they would be needed, but C#, for example, allows you to create extension methods for enums and MSDN has a decent real-world example of its use.
http://msdn.microsoft.com/en-us/library/bb383974.aspx I still don't understand why we would need string values (or any other non-integral type) but like you said Ben - if you need something like that you're not using the right datatype. Build a class. Here's my reasoning for enum values. enum Wood{ OAK, ASH, WILLOW, GOPHER } There's nothing in there that would necessitate needing a string value and really, if you need a string value, pass in a string as your parameter! Enumerations should be used to represent a set of data where the value itself isn't so important, it’s the consistency of the value that's important. It’s the fact that I've chosen gopher wood and I know that even though Wood::GOPHER really means "3", I don't have to remember what "3" represents because I can specifically type that I want gopher. -----Original Message----- From: Ben Schmidt [mailto:mail_ben_schm...@yahoo.com.au] Sent: Thursday, February 17, 2011 4:52 PM To: Martin Scotta Cc: Jarrod Nettles; Thomas Gutbier; internals@lists.php.net Subject: Re: [PHP-DEV] Re: Clarification on the Enum language structure >> Also, I feel like it should be restricted to integral types only, and >> defaults to a zero-based incrementing integer. This is more in line with >> other programming languages that already implement enums and will present >> "expected behavior" for people moving over to PHP. >> > for me that's a plain old interpretation of constants. > constant values were only integer values because of their implementation, > nowadays they could be anything you want, int, float, string and even > objects. I partially agree with that. I'm going to be a bit extreme here, but here's a thought: An enum is something you use conceptually for a set of constant values which aren't related in a numerical or other fashion (where another type would make more sense). In an enum, the only meaning of a constant is the meaning expressed in that constant's name. So you shouldn't want to use ints, floats, strings, certainly not objects, for enum values. If you feel yourself wanting to do this, an enum is not the right datatype for your purpose--you should be using one of those other types instead, possibly with a very few defined constants for commonly-used or 'magic' values. The issue, then, of what type underlies an enum is mostly to do with internal implementation, and more importantly, serialisation. Integers are the simplest and most obvious way to do this. But short strings, particularly string representations of the enum's symbols, could be a nice way to make serialised data more readable, and less fragile (e.g. if values are added to the enum, the mapping of strings to previous constants does not change, no matter where the new value is added). I see no reason to use floats or objects (or resources, or arrays, or ...). Ben. <html> <body> Jarrod Nettles Application Developer - Technology INCCRRA p 309.829.5327 - f 309.828.1808 This e-mail message may contain privileged or confidential information. If you are not the intended recipient, you may not disclose, use, disseminate, distribute, copy or rely upon this message or attachment in any way. If you received this e-mail message in error, please return by forwarding the message and its attachments to the sender. INCCRRA does not accept liability for any errors, omissions, corruption or virus in the contents of this message or any attachments that arises as a result of e-mail transmission. Please consider your environmental responsibility before printing this e-mail </body> </html> -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
