回复： [PHP-DEV] Thoughts on C version supported for PHP-Next

> > 发自我的 iPad > > > 在 2014年7月28日，22:20，Andrea Faulds <ajf@ajf.me (mailto:ajf@ajf.me)> > > 写道： > > > > > > On 28 Jul 2014, at 15:00, Derick Rethans <derick@php.net (mailto:derick@php.net)> > > wrote: > > > > > > Well, we don’t need to allow all of C99. We can simply allow using > > > > features that are widely supported and actually useful. For example, > > > > declarations between statements, > > > > > > > > > > > > > I think that makes code a lot less readable, so I would not be in favour > > > allowing this in our coding guidelines. > > > > > > > > > Really? I’ve found that declaring everything in advance makes for hard-to-read code. To > > take an example from code I’ve written (admittedly not C code - GML if anyone’s curious - but it > > might as well be), the first line of a function looked like this: > > > > var list, hashList, text, i, pluginname, pluginhash, realhash, url, handle, filesize, > > progress, tempfile, tempdir, failed, lastContact, isCached, env; > > > > Even broken onto multiple lines, declaring everything at once isn’t nice. For large > > functions (and some functions have to be large necessarily), declaring everything at the start just > > means a long list of variables and I would argue impairs code readability. > > > > You should declare variables when and where you need them. If everything is done at the > > top, you have to scroll up to check the type of a variable. It also means that now-unused variables > > are less obvious as the declarations are far away from the usage, so you probably won’t spot that > > it’s useless unless you look at your compiler warnings. > > > > Actually, a similar issue popped up in the code where that example was from. The language > > it was written in had some unfortunate properties, one of which was that variables not explicitly > > declared would instead be treated as properties of the current object. Because all the variables > > were declared at the start of the function, it was easy to miss the fact that some variables being > > used had not actually been declared. Of course this specific issue doesn’t exist in C, but it is > > an example of why having to declare all your variables at the start of a function isn’t really a > > good thing. > > > > If nothing else, I think we should use C99’s ability to declare variables between > > statements. It makes it more likely mistakes will be spotted, eases reading code, and as far as I am > > aware, is widely supported. > I really hate this. > Thanks +1, can’t agree more. Thanks, Wei Dai > > > > -- > > Andrea Faulds > > http://ajf.me/ > > > > > > > > > > > > -- > > PHP Internals - PHP Runtime Development Mailing List > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: http://www.php.net/unsub.php