Incrementing / Decrementing Operators
++
increment operator
--
decrement operator
Example Name Effect
---------------------------------------------------------------------
++$a Pre-increment Increments $a by one, then returns $a.
$a++ Post-increment Returns $a, then increments $a by one.
--$a Pre-decrement Decrements $a by one, then returns $a.
$a-- Post-decrement Returns $a, then decrements $a by one.
These can go before or after the variable.
If put before the variable, the increment/decrement operation is done to the variable first then the result is returned. If put after the variable, the variable is first returned, then the increment/decrement operation is done.
For example:
$apples = 10;
for ($i = 0; $i < 10; ++$i) {
echo 'I have ' . $apples-- . " apples. I just ate one.\n";
}
Live example
In the case above ++$i
is used, since it is faster. $i++
would have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with second's.
However, you must use $apples--
, since first, you want to display the current number of apples, and then you want to subtract one from it.
You can also increment letters in PHP:
$i = "a";
while ($i < "c") {
echo $i++;
}
Once z
is reached aa
is next, and so on.
Note that character variables can be incremented but not decremented and even so only plain ASCII characters (a-z and A-Z) are supported.
Stack Overflow Posts:
Actually, you are quite right when it comes to header/footer. Here is some basic information on how each of the major HTML5 tags can/should be used (I suggest reading the full source linked at the bottom):
section – Used for grouping together thematically-related content. Sounds like a div element, but it’s not. The div has no semantic meaning. Before replacing all your div’s with section elements, always ask yourself: “Is all of the content related?”
aside – Used for tangentially related content. Just because some content appears to the left or right of the main content isn’t enough reason to use the aside element. Ask yourself if the content within the aside can be removed without reducing the meaning of the main content. Pullquotes are an example of tangentially related content.
header – There is a crucial difference between the header element and the general accepted usage of header (or masthead). There’s usually only one header or ‘masthead’ in a page. In HTML5 you can have as many as you want. The spec defines it as “a group of introductory or navigational aids”. You can use a header in any section on your site. In fact, you probably should use a header within most of your sections. The spec describes the section element as “a thematic grouping of content, typically with a heading.”
nav – Intended for major navigation information. A group of links grouped together isn’t enough reason to use the nav element. Site-wide navigation, on the other hand belongs in a nav element.
footer – Sounds like its a description of the position, but its not. Footer elements contain informations about its containing element: who wrote it, copyright, links to related content, etc. Whereas we usually have one footer for an entire document, HTML5 allows us to also have footer within sections.
Source: https://clzd.me/html5-section-aside-header-nav-footer-elements-not-as-obvious-as-they-sound/
Additionally, here's a description on article
, not found in the source above:
article – Used for element that specifies independent, self-contained content. An article should make sense on its own. Before replacing all your div’s with article elements, always ask yourself: “Is it possible to read it independently from the rest of the web site?”
Best Answer
If we're discussing the frontend of the website, the particular line you've asked about....
is added to the Magento layout XML in app/design/frontend/base/default/layout/page.xml. In Magento version 1.8, you'll find it defined in lines 92-94.
By looking at the "type" attribute of this block tag, we can know what object class this section of the layout is. It comes from the "Core" module, and is of the block type Text List. The class name for this Mage_Core_Block_Text_List. (app/code/core/Mage/Core/Block/Text/List.php). Text Lists are simply block containers which purpose is to store additional child blocks inside them. You can add any number of child blocks to the text list and they will be rendered out either in the order they were added or the order they've been assigned.
So, to answer your question, there is no view script (.phtml file) that renders the contents of $this->getChildHtml('content'). The blocks which have been added to this block, may themselves have view scripts associated with them. To find out what view scripts those are, you'd have to find the layout XML which has added the block.
For example, if I had the following layout file added to the frontend of my website's theme:
The code above, would add the block with an object class of Mage_Core_Block_Template to the block with the name 'content' (which happens to be the one you asked about). Magento will then look for the view script in the following locations, in this order:
First one that is found, is the one it will use. If no view script is found Magento will log an error in
var/logs/system.log
(default log file setting) stating that the view script was not found. No output from the block will occur.Note that depending on your settings in System -> Configuration -> (General) Design, there may be additional
package/theme
locations Magento will look in. There are also other scenarios such as if the "Custom Theme" is field is changed for individual CMS Pages, Catalog Categories, or Catalog Products, these individual model's view page may have an additional view script location (that will match the selected theme) that takes precedence over your site's default settings.Magento will follow this same fallback logic when looking for translation files as well as layout XML files.
Please note, that it is perfectly acceptable to copy individual view scripts (avoid copying entire directories, copy over only view scripts you actually intend to modify) from
app/design/frontend/base/default/template/
to your local theme, and customize them for the purposes of your website's theme. However, in order to have an upgrade compatible site, layout files should not be copied from base to your local theme. Doing so, does not follow upgrade compatible practices. Instead, XML Layout updates for your theme should be contained inapp/design/frontend/PACKAGE_NAME/THEME_NAME/layout/local.xml
. There is no layout instructions fromapp/design/frontend/base/default/layout/*
, that cannot be removed/added-to/changed, what-have-you, with the proper XML instructions in local.xml.