PHPDoc for variable-length arrays of arguments - php

Is there a syntax for documenting functions which take a single configuration array, rather than individual parameters?
I'm thinking specifically of CodeIgniter-style libraries, which use a mechanism similar to this:
<?php
//
// Library definition
//
class MyLibrary {
var $foo;
var $bar;
var $baz;
// ... and many more vars...
/* Following is how CodeIgniter documents their built-in libraries,
* which is mostly useless. AFAIK they should be specifying a name
* and description for their #param (which they don't) and omitting
* #return for constructors
*/
/**
* #access public
* #param array
* #return void
*/
function MyLibrary($config = array()) {
foreach ($config as $key => $value) {
$this->$key = $value;
}
}
}
//
// Library usage:
//
// Iniitialize our configuration parameters
$config['foo'] = 'test';
$config['bar'] = 4;
$config['baz'] = array('x', 'y', 'z');
$x = new MyLibrary($config);
?>
So my question is, is there some supprted way of documenting the configuration array beyond just the purely textual description? Actually specifying a proper #param [type] [name] [desc] that allows PHPDoc to parse out useful values?
As an aside, CodeIgniter really does just overwrite it's own values with those passed in via the $config array as above, effectively allowing you to clobber private members. I'm not a fan, but I'm stuck with it.

I've never seen any "good" way of documenting this -- and I've never seen anything that could be used by IDEs (such as Eclipse PDT) for parameters hinting either :-(
I would have said "do like your framework does", but as you said, what it does, here, is not quite good enough...
Maybe a quick/sort list of possible keys might be better than nothing, though ; a bit like this :
#param array $config [key1=>int, otherKey=>string]
Not sure how it would be interpreted by phpDocumentor or an IDE... But might be worth a try ?
This is, btw, one reason why I tend to avoid that kind of way of passing parameters -- at least when there are not too many (optional) parameters to a method.

The correct array #param notation for arrays is as specified in PHPlint
You can use it to document a config array in a useful manner:
Example:
/**
* Does stuff
*
* #param array[int|string]array[string]Object $config
*
* #return array[int]string
*/
public function foo(array $config)
{
// do stuff here
return array('foo', 'bar', 'baz');
}

You can do this:
/**
* #param array $param1
* #param string $param1['hello']
*/
function hey($param1)
{
}
and netbeans will pick it up but phpdoc messes up the documentation

I always use <pre> tags in situations like this. Ex.:
/**
* #param array $ops An array of options with the following keys:<pre>
* foo: (string) Some description...
* bar: (array) An array of bar data, with the following keys:
* boo: (string) ...
* far: (int) ...
* baz: (bool) ...
* </pre>
*/
Most IDEs and documentation generators I have used seem to render this in a reasonable way, though of course they don't provide any type checking or inspection of the array parameters.

There is currently no "official" (as in 'supported by multiple tools') way to do this.
The PHP FIG is discussing it at the moment at https://groups.google.com/d/topic/php-fig/o4ko1XsGtAw/discussion

A text description, to whatever degree of completeness you want, is really your only option. You can make it as legible as you want, but code analysis tools (phpDocumentor, IDE support) have no way to know how your $array is actually structured at runtime.
I agree with the many commenters that writing code this way exchanges coding convenience for code legibility.

I've used classes.
<?php
class MyLibrary {
var $foo;
var $bar;
var $baz;
/**
* #param MyLibraryConfig|null $config
*/
function MyLibrary( $config = null ) {
if ( isset( $config->foo ) ) {
$this->foo = $config->foo;
}
if ( isset( $config->baz ) ) {
$this->baz = $config->baz;
}
if ( isset( $config->bar ) ) {
$this->bar = $config->bar;
}
}
}
/**
* #property string $foo
* #property int $bar
* #property array $baz
*/
class MyLibraryConfig {
}
It works fairly well, main problem is that the code becomes littered with specific classes. They can be nested so parts of configuration can be reused.

Related

How to document the types of arrays in PHPDoc, when those arrays are maps (aka hash tables)?

PHPDoc is the adaptation of JavaDoc to PHP. With the correct syntax in comments, you can use it to document the types of things. Tools such as IDEs can then use that metadata.
Here's an example using a 'simple' array of strings.
/**
* #param string[] $strings This parameter is blah blah blah.
*/
public function foo($strings) {
// ...
}
But PHP "arrays" can also be used as maps (aka hash tables aka dictionaries.) Here's an example from the PHP documentation (http://php.net/manual/en/language.types.array.php):
$array = array(
"foo" => "bar",
"bar" => "foo",
);
Now assume we modify our function foo to take things like $array above: an array of string => string.
/**
* #param ??????? entries This parameter is blah blah blah.
*/
public function foo($entries) {
// ...
}
How should the type of $entries be represented in PHPDoc?
http://www.phpdoc.org/docs/latest/guides/types.html#arrays doesn't even mention such a construct existing in the language.
You can at least document that $entries should be an array of strings:
/**
* #param string[] entries
*/
public function foo($entries)
{
// ...
}
However, you could also modify the method signature to add a type-declaration for array:
/**
* #param string[] entries
*/
public function foo(array $entries)
{
// ...
}
And furthermore, you could guard against invalid values being passed in by either writing your own assertions, or using, for example, beberlei/assert:
use Assert\Assertion;
/**
* #param string[] entries
*
* #throws InvalidArgumentException
*/
public function foo(array $entries)
{
Assertion::allString($entries);
Assertion::allString(array_keys($entries));
// ...
}
This doesn't help a lot with the docblock, but it documents the requirements in regard to your parameters in the code itself.
I would recommend to avoid using arrays for data structures in PHP code. Classes with explicitly defined properties are much more suitable.
As a workaround you can use stub classes to describe array structure, though you'll need to cast array to object to benefit from this.
$array = array(
"foo" => "bar",
"bar" => "foo",
);
/**
* #property $foo
* #property $bar
*/
class MyStub {}
/** #var MyStub $object */
$object = (object)$array;
// IDE completion and inspections are now available
$object->foo .= $object->bar;
// optional casting back to array
$array = (array)$object;

PHPStorm Type hinting array of different types

Is it possible in PHPStorm to type hint an array with different object types, ie:
public function getThings()
{
return array (new Thing(), new OtherThing(), new SomethingElse());
}
Even declaring them separately before building the array doesn't seem to work.
you can use phpdocs in order for phpstorm to accept an array of multiple types like so:
/**
* #return Thing[] | OtherThing[] | SomethingElse[]
*
*/
public function getThings()
{
return array (new Thing(), new OtherThing(), new SomethingElse());
}
This technique will make phpstorm think that the array could contain any of those objects and so it will give you type hinting for all three.
Alternatively you can make all of the objects extend another object or implement an interface and type hint that once object or interface like so:
/**
* #return ExtensionClass[]
*
*/
public function getThings()
{
return array (new Thing(), new OtherThing(), new SomethingElse());
}
This will give you type hints for only what the classes extend or implement from the parent class or interface.
I hope this helped!
This is described in the PHPDoc standards
https://github.com/phpDocumentor/fig-standards/blob/master/proposed/phpdoc.md#713-param
/**
* Initializes this class with the given options.
*
* #param array $options {
* #var bool $required Whether this element is required
* #var string $label The display name for this element
* }
*/
public function __construct(array $options = array())
{
<...>
}
In PHP, I've seen a very nice way of doing this:
#return array<Thing,OtherThing,SomethingElse>
IDEs like PHPStorm and VSCode understand this syntax pretty well. Hope this helps.

Auto-completion for Zend Form Elements

When creating form elements with Zend (using Zend Studio for Eclipse), I'd like some auto completion or hints. Here's what I'm thinking. I'm sure these exist, but I don't know how to get them.
I type createElement and auto-completes gives me the signature createElement($type, $name). Great, I select it.
but when I try to set the $type I don't get any hints like DateTextBox or ValidationTextBox. Being new, I see how this can be useful. What do you do to remember all the options?
for the array of attributes like require, invalidMessage, I'd like to get a list of those to choose from, and/or auto-complete when I start typing one.
// Date field
$date = $this->createElement('DateTextBox', 'date',
array('require' => 'true', 'invalidMessage' => 'Invalid date format')
);
$date->setLabel('date')->setRequired(true);
You have few options to help yourself, without waiting for any plugin:
learn it and remember ;)
extend your phpDoc blocks with all available options:
Example (to be honest I don't know if Eclipse supports html in phpDoc or even any text after variable name in #param, but it works fine in Netbeans):
/**
* [...]
* #param string $type Can be: <ul><li>DateTextBox</li><li>ValidationTextBox</li></ul>
* #param string $name Whatever
* #param array|Zend_Config $options Array with following keys: <ul><li>require</li><li>invalidMessage</li></ul>
* #return Zend_Form_Element
*/
public function createElement($type, $name, $options = null)
extend Zend class and create your own methods to simplify your work
Example:
class My_Zend_Form_Element extends Zend_Form_Element
{
public function createDateTextBox($name, $options = null)
{
return $this->createElement('DateTextBox', $name, $options);
}
}
declare some well named constants and provide some hint in phpDoc
Example: (type ZFE_OPTIONS and IDE should show hint with some constants to use as array keys)
/**
* Can be true or false
*/
define('ZFE_OPTIONS_REQUIRE','require');
create your own helper classes with methods to produce valid options array
Example:
class ZFE_Options
{
protected $opts = array();
/**
* #param bool $req
* #return ZFE_Options
*/
public function setRequired($req){
$this->opts['require'] = (bool)$req;
return $this;
}
/**
* #param string $txt
* #return ZFE_Options
*/
public function setInvalidMessage($txt){
$this->opts['invalidMessage'] = (string)$txt;
return $this;
}
/**
* #return array
*/
public function toArray(){
return $this->opts;
}
}
$zfe_options = new ZFE_Options();
$opts = $zfe_options
->setRequired(true)
->setInvalidMessage('Please provide valid email address')
->toArray();
That's not possible. It's not how autocompletion works. The hints you get are taken directly from ZF's code documentation. Nothing more, nothing less. Everything you see as hints is taken directly from the DocBlock and method signature, e.g.
/**
* Create an element
*
* Acts as a factory for creating elements. Elements created with this
* method will not be attached to the form, but will contain element
* settings as specified in the form object (including plugin loader
* prefix paths, default decorators, etc.).
*
* #param string $type
* #param string $name
* #param array|Zend_Config $options
* #return Zend_Form_Element
*/
public function createElement($type, $name, $options = null)
Eclipse can tell you to insert a string or an array and it will know that the method returns a Zend_Form_Element, but it cannot tell you what these strings should be.
The only place where I know something like what you describe exists is for CSS files. For some reason, when I type in display: it will give me an autocomplete box with possible values for this declaration. If you want more sophisticated autocomplete like this, consider filing this as a feature request to Zend.

How to use phpDoc with overloaded methods?

Let's say I have a PHP class called Color, it's constructor accepts various params.
// hex color
$myColor = new Color('#FF008C');
// rgb channels
$myColor = new Color(253,15,82);
// array of rgb channels
$myColor = new Color(array(253,15,82));
// X11 color name
$myColor = new Color('lightGreen');
How should I use phpDoc to create API documentation for constructor and other methods like this?
How to use phpDoc with overloaded methods?
class Color {
/**
* Constructor
* what should be here?
*/
public function __construct() {
/* CODE */
}
}
Just my point of view, but you should not have multiple constructors in the first place - your constructor is going to be full of if/else-ladders, which really isn't a good idea, especially for something lightweight like a representation of a Color.
I strongly encourage you to try something like this instead:
class Color
{
protected function __construct($r, $g, $b)
{ ... }
public static function fromHex($hex) {
return new Color(...);
}
public static function fromRGB($r, $g, $b) { ... }
public static function fromArray(array $rgb) { ... }
...
}
Now, in consumer code, instead of somewhat mysterious and ambiguous constructor calls like these:
$a = new Color(0,0,0);
$b = new Color('#000000');
Instead you can have more legible and semantic consumer code, like this:
$a = Color::fromRGB(0,0,0);
$b = Color::fromHex('#000000');
This probably makes more sense to somebody reading the consumer code, it eliminates the logic required to make the ambiguous constructor work, and as a bonus (if you're using an IDE such as PhpStorm) you can have all your inspections pass. If you're running a documentation generator, this also ensures that all the options are documented individually, rather than lumped together in a verbal description.
Note that I declared the constructor protected - this is a personal preference, but if I'm going to have multiple static factory-methods, I prefer to see those consistently used in consumer code, rather than sometimes seeing Color::fromRGB(...) and other times new Color(...).
I think that is better to use #method annotation for class/interface, which declares overloading methods. This question is interesting for me too.
/**
* #method void setValue(int $value)
* #method void setValue(string $value)
* #method void setValue(string $value, int $startFrom)
*/
class Example
{
public function setValue($arg1, $arg2)
{
// ...
}
}
See http://phpdoc.org/docs/latest/references/phpdoc/tags/method.html
Because you allow variable length arguments there are two ways I would do this.
I would simply list the allowed arguments are parameters.
/**
* #param mixed $arg1 ... description
* #param mixed $arg2 ... description
* #param mixed $arg3 ... description
*/
public function __construct() {}
Or I would simply provide an explanation with some examples.
/**
* Explanation of different expected argument combinations.
*/
public function __construct() {}
Another alternative, since only one of the examples has more than one argument, would be to simply define the arguments in the method signature making the last 2 optional. Like this:
/**
* #param mixed $arg1 ...
* #param int $arg2 ...
* #param int $arg3 ...
*/
public function __construct($arg1, $arg2 = null, $arg3 = null) {}
I know of no elegant way to do this with phpDoc. The phpDoc comment/api formatting is based on a the Javadoc format. Javadoc doesn't have a feature set to support this because in java, if you want a method to have a variable number of arguments you re-declare the method prototype for each variation.
public double foo() {
}
public double foo(double my_param) {
}
So, my performance preference is to do something like
/**
* My General description
*
* Here explain what each argument combination can do
* #param mixed $arg1 can be array, string, hex as string, or int
* #param int $arg2 if arg1 is int, then this is etc, otherwise optional
* #param int $arg3 if ar1 is int, then this is etc, otherwise optional
*/
but this may not play nice with the various auto-documentation tools.
The according to Hoyle way to accomplish this can be found at the phpDoc site.

Does PHP have built-in data structures?

I'm looking at the PHP Manual, and I'm not seeing a section on data structures that most languages have, such as lists and sets. Am I just blind or does PHP not have anything like this built in?
The only native data structure in PHP is array. Fortunately, arrays are quite flexible and can be used as hash tables as well.
http://www.php.net/array
However, there is SPL which is sort of a clone of C++ STL.
http://www.php.net/manual/en/book.spl.php
PHP offers data structures through the Standard PHP Library (SPL) basic extension, which is available and compiled by default in PHP 5.0.0.
The data structures offered are available with PHP 5 >= 5.3.0, and includes:
Doubly Linked Lists
A Doubly Linked List (DLL) is a list of nodes linked in both directions to each others. Iterator’s operations, access to both ends, addition or removal of nodes have a cost of O(1) when the underlying structure is a DLL. It hence provides a decent implementation for stacks and queues.
SplDoublyLinkedList class
SplStack class
SplQueue class
Heaps
Heaps are tree-like structures that follow the heap-property: each node is greater than or equal to its children, when compared using the implemented compare method which is global to the heap.
SplHeap class
SplMaxHeap class
SplMinHeap class
SplPriorityQueue class
Arrays
Arrays are structures that store the data in a continuous way, accessible via indexes. Don’t confuse them with PHP arrays: PHP arrays are in fact implemented as ordered hashtables.
SplFixedArray class
Map
A map is a datastructure holding key-value pairs. PHP arrays can be seen as maps from integers/strings to values. SPL provides a map from objects to data. This map can also be used as an object set.
SplObjectStorage class
Source: http://php.net/manual/en/spl.datastructures.php
PHP 7 introduced an extension called ds providing specialized data structures as an alternative to the array.
The ds,
uses the Ds\ namespace.
has 3 interfaces namely,Collection, Sequence and Hashable
has 8 classes namely, Vector, Deque,Queue, PriorityQueue, Map, Set, Stack, and Pair
For more information checkout the Manual and also This blog post has some awesome information including benchmarks.
The associative array can be used for most basic data structures hashtable, queue, stack. But if you want something like a tree or heap I don't think they exist by default but I'm sure there are free libraries anywhere.
To have an array emulate a stack use array_push() to add and array_pop() to take off
To have an array emulate a queue use array_push() to enqueue and array_shift() to dequeue
An associative array is a hash by default. In PHP they are allowed to have strings as indexes so this works as expected:
$array['key'] = 'value';
Finally, you can kind of emulate a binary tree with an array with the potential to have wasted space. Its useful if you know you're going to have a small tree. Using a linear array, you say for any index (i) you put its left child at index (2i+1) and right child at index (2i+2).
All of these methods are covered nicely in this article on how to make JavaScript arrays emulate higher level data structures.
PHP has arrays, which are actually associative arrays and can also be used as sets. Like many interpreted languages, PHP offers all this under one hood instead of providing different explicit data types.
E.g.
$lst = array(1, 2, 3);
$hsh = array(1 => "This", 2 => "is a", 3 => "test");
Also, take a look in the manual.
PHP's array doubles as both a list and a dictionary.
$myArray = array("Apples", "Oranges", "Pears");
$myScalar = $myArray[0] // == "Apples"
Or to use it as an associative array:
$myArray = array("a"=>"Apples", "b"=>"Oranges", "c"=>"Pears");
$myScalar = $myArray["a"] // == "Apples"
I think you might want to be a bit more specific, when you say data structures my mind goes in a few directions...
Arrays - They are certainly well documented and available in. (http://us.php.net/manual/en/book.array.php)
SQL Data - Depends on the database you are using, but most are available. (http://us.php.net/manual/en/book.mysql.php)
OOP - Depending on the version objects can be designed and implemented. (http://us.php.net/manual/en/language.oop.php) I had to search for OOP to find this on the php site.
Of course PHP has data structures. The array in php is incredibly flexible. Some examples:
$foo = array(
'bar' => array(1,'two',3),
'baz' => explode(" ", "Some nice words")
);
Then you have an absolute plethora of array functions available to map/filter/walk/etc the structures, or convert, flip, reverse, etc.
You can always create your own if you don't feel PHP includes a specific type of data structure. For example, here is a simple Set data structure backed by an Array.
class ArraySet
{
/** Elements in this set */
private $elements;
/** the number of elements in this set */
private $size = 0;
/**
* Constructs this set.
*/
public function ArraySet() {
$this->elements = array();
}
/**
* Adds the specified element to this set if
* it is not already present.
*
* #param any $element
*
* #returns true if the specified element was
* added to this set.
*/
public function add($element) {
if (! in_array($element, $this->elements)) {
$this->elements[] = $element;
$this->size++;
return true;
}
return false;
}
/**
* Adds all of the elements in the specified
* collection to this set if they're not already present.
*
* #param array $collection
*
* #returns true if any of the elements in the
* specified collection where added to this set.
*/
public function addAll($collection) {
$changed = false;
foreach ($collection as $element) {
if ($this->add($element)) {
$changed = true;
}
}
return $changed;
}
/**
* Removes all the elements from this set.
*/
public function clear() {
$this->elements = array();
$this->size = 0;
}
/**
* Checks if this set contains the specified element.
*
* #param any $element
*
* #returns true if this set contains the specified
* element.
*/
public function contains($element) {
return in_array($element, $this->elements);
}
/**
* Checks if this set contains all the specified
* element.
*
* #param array $collection
*
* #returns true if this set contains all the specified
* element.
*/
public function containsAll($collection) {
foreach ($collection as $element) {
if (! in_array($element, $this->elements)) {
return false;
}
}
return true;
}
/**
* Checks if this set contains elements.
*
* #returns true if this set contains no elements.
*/
public function isEmpty() {
return count($this->elements) <= 0;
}
/**
* Get's an iterator over the elements in this set.
*
* #returns an iterator over the elements in this set.
*/
public function iterator() {
return new SimpleIterator($this->elements);
}
/**
* Removes the specified element from this set.
*
* #param any $element
*
* #returns true if the specified element is removed.
*/
public function remove($element) {
if (! in_array($element, $this->elements)) return false;
foreach ($this->elements as $k => $v) {
if ($element == $v) {
unset($this->elements[$k]);
$this->size--;
return true;
}
}
}
/**
* Removes all the specified elements from this set.
*
* #param array $collection
*
* #returns true if all the specified elemensts
* are removed from this set.
*/
public function removeAll($collection) {
$changed = false;
foreach ($collection as $element) {
if ($this->remove($element)) {
$changed = true;
}
}
return $changed;
}
/**
* Retains the elements in this set that are
* in the specified collection. If the specified
* collection is also a set, this method effectively
* modifies this set into the intersection of
* this set and the specified collection.
*
* #param array $collection
*
* #returns true if this set changed as a result
* of the specified collection.
*/
public function retainAll($collection) {
$changed = false;
foreach ($this->elements as $k => $v) {
if (! in_array($v, $collection)) {
unset($this->elements[$k]);
$this->size--;
$changed = true;
}
}
return $changed;
}
/**
* Returns the number of elements in this set.
*
* #returns the number of elements in this set.
*/
public function size() {
return $this->size;
}
/**
* Returns an array that contains all the
* elements in this set.
*
* #returns an array that contains all the
* elements in this set.
*/
public function toArray() {
$elements = $this->elements;
return $elements;
}
}
PHP can also have an array of arrays which is called a "multidimensional array" or "matrix". You can have 2-dimensional arrays, 3-dimensional arrays, etc.

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