`#[php_impl]`

You can export an entire impl block to PHP. This exports all methods as well as constants to PHP on the class that it is implemented on. This requires the #[php_class] macro to already be used on the underlying struct. Trait implementations cannot be exported to PHP.

If you do not want a function exported to PHP, you should place it in a separate impl block.

Methods

Methods basically follow the same rules as functions, so read about the php_function macro first. The primary difference between functions and methods is they are bounded by their class object.

Class methods can take a &self or &mut self parameter. They cannot take a consuming self parameter. Static methods can omit this self parameter.

To access the underlying Zend object, you can take a reference to a ZendClassObject<T> in place of the self parameter, where the parameter is annotated with the #[this] attribute. This can also be used to return a reference to $this.

By default, all methods are renamed in PHP to the camel-case variant of the Rust method name. This can be changed on the #[php_impl] attribute, by passing one of the following as the rename_methods option:

"none" - does not rename the methods.
"camelCase" - renames all methods to camel case (default).
"snake_case" - renames all methods to snake case.

For example, to disable renaming, change the #[php_impl] attribute to #[php_impl(rename_methods = "none")].

The rest of the options are passed as separate attributes:

#[defaults(i = 5, b = "hello")] - Sets the default value for parameter(s).
#[optional(i)] - Sets the first optional parameter. Note that this also sets the remaining parameters as optional, so all optional parameters must be a variant of Option<T>.
#[public], #[protected] and #[private] - Sets the visibility of the method.
#[rename("method_name")] - Renames the PHP method to a different identifier, without renaming the Rust method name.

The #[defaults] and #[optional] attributes operate the same as the equivalent function attribute parameters.

Constructors

By default, if a class does not have a constructor, it is not constructable from PHP. It can only be returned from a Rust function to PHP.

Constructors are Rust methods which can take any amount of parameters and returns either Self or Result<Self, E>, where E: Into<PhpException>. When the error variant of Result is encountered, it is thrown as an exception and the class is not constructed.

Constructors are designated by either naming the method __construct or by annotating a method with the #[constructor] attribute. Note that when using the attribute, the function is not exported to PHP like a regular method.

Constructors cannot use the visibility or rename attributes listed above.

Constants

Constants are defined as regular Rust impl constants. Any type that implements IntoZval can be used as a constant. Constant visibility is not supported at the moment, and therefore no attributes are valid on constants.

Property getters and setters

You can add properties to classes which use Rust functions as getters and/or setters. This is done with the #[getter] and #[setter] attributes. By default, the get_ or set_ prefix is trimmed from the start of the function name, and the remainder is used as the property name.

If you want to use a different name for the property, you can pass a rename option to the attribute which will change the property name.

Properties do not necessarily have to have both a getter and a setter, if the property is immutable the setter can be omitted, and vice versa for getters.

The #[getter] and #[setter] attributes are mutually exclusive on methods. Properties cannot have multiple getters or setters, and the property name cannot conflict with field properties defined on the struct.

As the same as field properties, method property types must implement both IntoZval and FromZval.

Example

Continuing on from our Human example in the structs section, we will define a constructor, as well as getters for the properties. We will also define a constant for the maximum age of a Human.

#![cfg_attr(windows, feature(abi_vectorcall))]
extern crate ext_php_rs;
use ext_php_rs::{prelude::*, types::ZendClassObject};
#[php_class]
#[derive(Debug, Default)]
pub struct Human {
    name: String,
    age: i32,
    #[prop]
    address: String,
}
#[php_impl]
impl Human {
    const MAX_AGE: i32 = 100;

    // No `#[constructor]` attribute required here - the name is `__construct`.
    pub fn __construct(name: String, age: i32) -> Self {
        Self { name, age, address: String::new() }
    }

    #[getter]
    pub fn get_name(&self) -> String {
        self.name.to_string()
    }

    #[setter]
    pub fn set_name(&mut self, name: String) {
        self.name = name;
    }

    #[getter]
    pub fn get_age(&self) -> i32 {
        self.age
    }

    pub fn introduce(&self) {
        println!("My name is {} and I am {} years old. I live at {}.", self.name, self.age, self.address);
    }

    pub fn get_raw_obj(#[this] this: &mut ZendClassObject<Human>) {
        dbg!(this);   
    }

    pub fn get_max_age() -> i32 {
        Self::MAX_AGE
    }
}
#[php_module]
pub fn get_module(module: ModuleBuilder) -> ModuleBuilder {
    module
}
fn main() {}

Using our newly created class in PHP:

<?php

$me = new Human('David', 20);

$me->introduce(); // My name is David and I am 20 years old.
var_dump(Human::get_max_age()); // int(100)
var_dump(Human::MAX_AGE); // int(100)

ext-php-rs

#[php_impl]