&str

A borrowed string. When this type is encountered, you are given a reference to the actual zend string memory, rather than copying the contents like if you were taking an owned String argument.

Note that you cannot expect the function to operate the same by swapping out String and &str - since the zend string memory is read directly, this library does not attempt to parse double types as strings.

See the String for a deeper dive into the internal structure of PHP strings.

Rust example

#![cfg_attr(windows, feature(abi_vectorcall))]
extern crate ext_php_rs;
use ext_php_rs::prelude::*;
#[php_function]
pub fn str_example(input: &str) -> String {
    format!("Hello {}", input)
}

#[php_function]
pub fn str_return_example() -> &'static str {
    "Hello from Rust"
}
fn main() {}

PHP example

<?php

var_dump(str_example("World")); // string(11) "Hello World"
var_dump(str_example(5)); // Invalid

var_dump(str_return_example());