Monday, October 14, 2013

In which I stumble over PHP

his post was originally just called "learning by doing," but then I was feeling so embarrassed about not recognizing PHP when I fell over it that I renamed it. This post is also on understanding the elements of hook_help() in general in order to write views_help(). Warning: contains questions that are not-stupid!

1. What does $output = ''; do, exactly?
This is most likely a PHP thing, which I have absolutely zero experience with. I know $ as jQuery, but now I'm not even sure that's what it's doing here. Yeah, that would be PHP- the $ indicates a variable. I've been avoiding learning PHP for the timebeing in the interest of focusing elsewhere without distraction, but a quick look through the PHP online documentation will help me with the syntax here. This explains why no one answered my pathetic pleas for explanation on this previously. I feel pretty dumb for not recognizing/thinking of this right off. The functions look enough like functions that I wasn't paying much attention to details, but... yeah.

So, question part B: why so many lines for defining $output? Why not in one big block? Is that just for readability, using a new line of PHP for what would be a new line of HTML? The first line $output = ''; is just initializing the output variable, or rather, defining it. Subsequent lines $output .= ''; are concatenating, or adding, those strings onto the previous definitions. Now I'm looking at coding best practices for Drupal and for PHP. This also spills over into question 2, below.

2. $output .= '<h3>' . t('About') . '</h3>'; What are the periods doing in there? 

The separation of html elements and the string to be translated makes sense, no reason to include code in translatable strings. The periods seem to be for concatenation of strings/elements in the $output variable, since otherwise just using = would reassign the entire variable.

In alexpott's Drupalcon Prague session From Not-Invented-Here to Proudly-Found-Elsewhere: A Drupal 8 Story, he recommends PHP The Right Way, which just happens to have a few more opinions on things than the standard PHP docs (new version in beta!).

In PHP The Right Way, we find a note on concatenation recommending that strings be kept under 120 characters, and that if they should be longer, to use concatenation operators (eg a period, . ) combined with indented newlines for readability. This method is recommended over using concatenating assignment operators (eg period equals, .= ). The example of what not to do looks exactly like our $output variable here.

... which means I found the right bit of doc! and that it's usually impossible to keep up with standards, best practices and the latest in code. Plus, I'm sure I'm still missing some reasoning and background here.

3. More on the translate function t():

In views_help() the translate function is part of the concatenated string assigned to $output. In point two, above, it marks the string "About" as translatable: t('About'). Whatever is inside the translate function is added to the database of strings to be translated into the current language from English, which is the standard. The translate function works with the Localization API to pick out which bits of text are translatable.

The Localization API seems to mostly do the work of targeting strings for translation either through a translate function or "known locations." The translate function identifies strings, and the Localization Server extracts them. You know, I'm a somewhat visual person, I just keep wanting maps for all these things.

EDIT: This bit from the Drupal JS API docs finally explains how the translate function works:
The Drupal.locale property works in conjunction with Drupal.t(), the JavaScript equivalent of the server-side t() function. It holds a collection of string translations so that Drupal.t() can then access the required string from Drupal.locale in order to translate what was passed into it.

4. What are these link tokens? ! is preferable to @?

After my preliminary expectations of easiness on this one were doused, I think I at least determined that this is not the same sort of token as the generic placeholder substitution token. It seems that instead of just using <a> tags, links are created using link tokens and an array. Previously, the links were marked with @, but from a comment on the views_help issue I've gathered that ! is the new @. Perhaps this is another PHP thing. Perhaps I will just go read my PHP books now and call it quits on this blogpost.

Read next: Working with JS in Drupal

And in the meantime: watch session slideshows from DrupalCon Prague! I'm so happy these are available.

And also, finally went to do something with Drush and found it not cooperating, so now I need to backtrack on that, put it back together, and hope that the latest version is really the right thing for D8. Oh, now I really feel dumb. Should have watched this session from Prague first, too. Somewhere in the process of downloading the latest, adjusting .bash_profile and connecting to the example aliases file, I broke it even worse. And creating a mysql file somewhere to cooperate with MAMP.

All this is in the notes on the Drush github page, of course, but after a while I just started feeling like a complete moron. Finally figured out that drush self-update is no longer included (I must've had a much older version installed earlier, not sure how/why), found a drush cheatsheet, and managed to uninstall my modules, check my modules, reinstall... I think I've got it now, but jeez. I keep getting stuck between versions, missing important documentation and feeling really lost, which is incredibly discouraging because then I can't even begin to do simple tasks. Hopefully if I just keep chugging along it'll all work eventually.