This document provides an introduction and recap of server-side programming concepts covered in Lesson Three, including data types, operators, order of operations, programming blocks, coding conventions, and good and bad coding practices. It discusses literals, arithmetic, assignment, comparison operators, string operators, order of operations, programming blocks, coding conventions, readability, and provides examples. It also assigns students to identify good and bad code examples based on coding style and to fetch and merge code from an upstream repository.

1. INTRO TO SERVER SIDE PROGRAMMING
Lesson Three
Friday, September 13, 13

2. Recap - What Have We Found?
Literals
boolean - True/False
integer
float - decimal numbers
string - text
array - ordered key/value pairs
object - literal within class
Null - no value
Friday, September 13, 13

3. Recap Continued
Operators
Arithmetic - $newvalue = $oldvalue + 1;
Assignment - $newervalue = 10;
Comparison - $newvalue != $oldvalue;
String Operators
var_dump('foo' . 'bar');
$a = 'foo'; a .= 'bar';
var_dump($a);
Friday, September 13, 13

4. Order of Operations
PHP (and most languages) follows Operator
Precedence rules
These allow for unambiguous statements
Parentheses can be used to override default
Operator Precedence or to add visual clarity
$taxable_income = $wages + $earnings - $deductions;
$taxable_income = $wages + ( $earnings - $deductions );
Friday, September 13, 13

5. Programming Blocks
Blocks are sections of code grouped together
Blocks consist of declarations and statements
PHP organizes statements into blocks with { }
Conventions dictate indentation for readability
{$foo=$bar+$bat;echo $foo;}
{
$foo = $bar + $bat;
echo $foo;
}
Friday, September 13, 13

6. Coding Conventions
A set of guidelines for a specific programming
language of recommended styles, practices &
methods for each aspect of a program
Covers things like file organization, indentation,
comments, declarations, statements, white space,
naming conventions, practices & principles
This improves the readability of code and makes
software maintenance easier.
Conventions enforced by humans, not compilers
Friday, September 13, 13

7. Ease of Reading/Ease of Use
$UP=6;DN=19;$x=0;
while(++$x<=24){echo "hour $x: "; if($x>+$UP&&$X<+$DN);
echo "sun is up"; else echo "sun is down": echo "n"; }
define( 'SUNRISE', 6 );
define( 'SUNSET', 19 );
$hours = range( 1, 24);
foreach ( $hours as $hour ) {
// ternary operation
$up_or_down = ( (
$hour >= SUNRISE and
$hour <= SUNSET
) ? 'up' : 'down' );
echo "hour {$hour}: ",
"sun is {$up_or_down}",
"n";
}
Friday, September 13, 13

8. ASSIGNMENT 3.1
Good Code, Bad Code
Friday, September 13, 13

9. Good Code, Bad Code
Log in to Github, then into Cloud9 Using Github
Look through your forked projects for a block
(~100) lines of code that are either very hard or
very easy to read based on the coding style
Copy & paste into a file named assignment-4.1.md
Make a list with your partner of ways that the code
style could be improved in each of your examples
Save files to share with the class. Push to Github?
(https://help.github.com/articles/create-a-repo)
Friday, September 13, 13

10. Git and Github - Here to Help
Git is your robot friend that remembers what you
tell it to remember, and only that
This robot recognizes when things have changed
It knows how to remember, just not when
Git can tell you what changed and when, you use
comments to tell it (and yourself) why
If you ask nicely (-h or --help) the robot will help
This robot is well organized and can track
branches of changed code
Friday, September 13, 13

11. Basic git Commands
git branch - what branches are there & which am I on?
git status - what files have I changed or created?
git add (files) - consider this stuff for remembering
git commit (files) - I really want you to remember what I've
considered via git add
git push [remote [branch] ] - tell the robot named
"remote" (default is "origin") about my changes in
"branch" (default is "master")
git fetch [remote] - ask the robot named "remote" for changes or
branches that you don't know about yet
git merge [branch] - attempt to combine changes in "branch"
Friday, September 13, 13

12. ASSIGNMENT 3.2
fetch and merge
Friday, September 13, 13

13. Let's Merge Again
In Cloud 9:
git remote add upstream
https://github.com/vc-dig1108-fall-2013/assignments.git
git fetch upstream
git merge upstream/master
Open the file named "homework-4.1.md"
Add your name to bottom of the file and save
Commit the file & push to your Github acct. (hint: "origin")
https://help.github.com/articles/create-a-repo
https://help.github.com/articles/fork-a-repo
Friday, September 13, 13