docs: add "Things about PHP" slides

things-to-know-php/sections/getting-started.rst

@@ -0,0 +1,257 @@
+.. page:: titlePage
+
+.. class:: centredTitle
+
+How do I get started?
+
+.. page::
+
+.. class:: centredTitle
+
+``php -v``
+
+.. page::
+
+``PHP 8.1.0 (cli) (built: Nov 30 2021 07:15:23) (NTS)
+Copyright (c) The PHP Group
+Zend Engine v4.1.0, Copyright (c) Zend Technologies``
+
+.. page::
+
+.. class:: centredTitle
+
+``vim index.php``
+
+.. raw:: pdf
+
+   TextAnnotation "Create a new file called 'index.php' in the text editor of your choice."
+
+.. page:: standardPage
+
+Your first PHP file
+===================
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   // index.php
+
+.. raw:: pdf
+
+   TextAnnotation "Add an opening tag (closing tag is optional, and in some cases should not be used)."
+   
+Your first PHP file
+===================
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   // index.php
+
+   echo 'Hello World';
+
+.. page:: titlePage
+
+.. class:: centredTitle
+
+``php index.php``
+
+.. page::
+
+.. class:: centredTitle
+
+``php -S localhost:8000``
+
+.. page:: titlePage
+
+``/app # php -S localhost:8000``
+
+``[Tue Mar  8 20:52:39 2022] PHP 8.1.0 Development Server
+(http://localhost:8000) started``
+
+.. raw:: pdf
+
+   TextAnnotation "PHP's local development web server. Fine for simple scripts or apps."
+
+.. page:: imagePage
+
+.. image:: images/hello-world.png
+   :width: 23cm
+
+.. page:: titlePage
+
+.. class:: centredTitle
+
+``docker run --rm
+-v $PWD:/app
+-w /app
+php:8.1-cli-alpine
+php index.php``
+
+.. page::
+
+.. class:: centredTitle
+
+``docker run --rm
+-v $PWD:/app
+-w /app
+php:7.4-cli-alpine
+php index.php``
+
+.. raw:: pdf
+
+    TextAnnotation "7.4 instead of 8.1"
+
+.. page::
+
+.. class:: centredTitle
+
+``docker run --rm
+-v $PWD:/var/www/html
+-p 80:80
+php:8.1-apache``
+
+.. raw:: pdf
+
+    TextAnnotation "Apache rather than CLI"
+
+.. page:: standardPage
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+    // index.php
+
+    function say()
+    {
+        echo 'Hello!';
+    }
+
+
+.. raw:: pdf
+
+    TextAnnotation "Global function."
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+    // index.php
+
+    function say($value)
+    {
+        echo $value;
+    }
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+    // index.php
+
+    function say(string $value): void
+    {
+        echo $value;
+    }
+
+.. raw:: pdf
+
+   TextAnnotation "In PHP 7, we can declare type hints on scalar values (e.g. string). Arrays and classes were possible in previous versions."
+   TextAnnotation "We can also declare a return type. In this case, there is nothing returned, so the return type is `void`."
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+    // index.php
+
+    function say(string $value): string
+    {
+        return $value;
+    }
+
+.. raw:: pdf
+
+   TextAnnotation "Return a string rather than echoing a string."
+
+.. page::
+
+.. code-block:: php
+    :linenos:
+
+    <?php
+
+    // src/Person.php
+
+    class Person
+    {
+        public function say(string $value): void
+        {
+            echo $value;
+        }
+    }
+
+.. raw:: pdf
+
+   TextAnnotation "Move it into a class called `Person`. Function now becomes a method, though behaves in exactly the same way."
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   // Version 1.
+   say();
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   // Version 1.
+   say();
+
+   // Version 2.
+   say('something');
+
+.. raw:: pdf
+
+   TextAnnotation "First version with no arguments."
+   TextAnnotation "Second version providing the text as an argument."
+   TextAnnotation "Third version using the Person class."
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   // Version 1.
+   say();
+
+   // Version 2.
+   say('something');
+
+   // Version 3.
+   $person = new Person();
+   $person->say('something');