Re: speaking of control structures...

On Tue, 2009-05-05 at 13:56 -0400, Tom Worster wrote: > there's a control structure i wish php had: a simple block that you can > break out of, e.g. > > block { > > if ( condition ) > break; > > blah... > blah... > > if ( another condition ) > break; > > blah... > blah... > > etc... > > } > > the block is just like a loop except that it is executed once only. > > this would be a handy structure for writing input validation code. the blah > blah fragments can be used for opening files, talking to the db, > manipulating strings, processing dates and times, etc., the conditions for > testing if the input is unacceptable. > > i'm sure many of the programmers here do this kind of thing routinely and > have their own habits and solutions. i'd be curious what they are. please > let us know! > > > i guess i ought to go first. it's fugly but it works: > > $once = true; > while ( $once ) { > $once = false; > > stuff using break where needed ... > > } You can do it simpler: <?php while( $condition ) { // stuff using break where needed. // final break break; } ?> But PHP 5.3 introduces goto: <?php header: if( $something ) ... goto body; body: if( $soemthingElse ) ... goto footer; if( $seomthingerElse ) ... goto footer; footer: // blah blah blah goto done; done; ?> Sometimes goto can make your code more succinct AND readable-- Dijkstra be damned on this point-- All hail Knuth! And no, I'm not saying this particular example is a good example of when goto is useful... but it does illustrate not having to contort variables and logic into a nightmare of complexity and unintuitiveness to satisfy "Structured Programming" paradigms. Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP