Merge pull request #363 from astorm/gh-pages

Rewrite to remove inaccurate @ logging text.

_posts/08-02-01-Errors.md

@@ -59,39 +59,33 @@ You can also control whether or not errors are displayed to the screen (good for
 
 ### Inline Error Suppression
 
-You can also suppress specific errors from being displayed using the Error Control Operator `@`. You simply put 
-this operator at the beginning an expression, and any error that would be caused as a direct result of the specific
-expression will be silenced.
+You can also tell PHP to suppress specific errors with the Error Control Operator `@`. You put 
+this operator at the beginning of an expression, and any error that's a direct result of the expression is silenced. 
 
 {% highlight php %}
 echo @$foo['bar'];
 {% endhighlight %}
 
 This will output `$foo['bar']` if it exists, but will simply return a null and print nothing if the variable `$foo` or 
-`'bar'` key does not exist. 
+`'bar'` key does not exist.  Without the error control operator, this expression could create a `PHP Notice:  Undefined variable: foo` or `PHP Notice:  Undefined index: bar` error.
 
-This might seem like a good idea, but due to the way PHP actually handles `@` it is incredibly unperformant, and has the 
-unexpected effect of still actually logging the error anyway. If you have this code in a loop that runs 100 times in an
-instance, and you run that 1 million times, then you've got 100 million lines in your logs. 
+This might seem like a good idea, but there are a few undesirable tradeoffs.  PHP handles expressions using an `@` in a less performant way than expressions without an `@`.  Premature optimization may be the root of all programming arguments, but if performance is particularly important for your application/library it's important to understand the error control operator's performance implications. 
 
-Instead, use the following:
+Secondly, the error control operator **completely** swallows the error.  The error is not displayed, and the error is not send to the error log. Also, stock/production PHP systems have no way to turn off the error control operator. While you may be correct that the error you're seeing is harmless, a different, less harmless error will be just as silent.  
+
+If there's a way to avoid the error suppression operator, you should consider it.  For example, our code above could be rewritten like this
 
 {% highlight php %}
 echo isset($foo['bar']) ? $foo['bar'] : '';
 {% endhighlight %}
 
-This will be much quicker, and save filling up your logs with junk. [SitePoint] go a step further and say you should 
-[never suppress notices] with `@`.
-
 One instance where error suppression might make sense is where `fopen()` fails to find a file to load. You could check 
-for existence of the file before you try to load it, but if the file is deleted after the check and before the `fopen()` 
+for the existence of the file before you try to load it, but if the file is deleted after the check and before the `fopen()` 
 (which might sound impossible, but it can happen) then `fopen()` will return false _and_ throw an error. This is
 potentially something PHP should resolve, but is one case where error suppression might seem like the only valid 
 solution.
 
-In a stock PHP system, the behavior of the error control operator is irreversible. There are no configuration settings which allow a suppressed error to be temporarily un-suppressed.  
-
-However, [xDebug] has an `xdebug.scream` ini setting which will disable the error control operator.  You can set this via your `php.ini` file with the following.
+Earlier we mentioned there's no way in a stock PHP system to turn off the error control operator.  However, [xDebug] has an `xdebug.scream` ini setting which will disable the error control operator.  You can set this via your `php.ini` file with the following.
 
     xdebug.scream = On
     
@@ -108,7 +102,6 @@ This is most useful when you're debugging code and suspect an informative error
 
 * [Error Control Operators](http://php.net/manual/en/language.operators.errorcontrol.php)
 * [SitePoint](http://www.sitepoint.com/)
-* [never suppress notices](http://www.sitepoint.com/why-suppressing-notices-is-wrong/)
 * [xDebug](http://xdebug.org/docs/basic) 
 * [Scream](http://www.php.net/manual/en/book.scream.php)