Primitive Numbers

Primitive integers include i8, i16, i32, i64, u8, u16, u32, u64, isize, usize, f32 and f64.

Note that internally, PHP treats all of these integers the same (a 'long'), and therefore it must be converted into a long to be stored inside the zval. A long is always signed, and the size will be 32-bits on 32-bit platforms and 64-bits on 64-bit platforms.

Floating point numbers are always stored in a double type (f64), regardless of platform. Note that converting a zval into a f32 will lose accuracy.

This means that converting i64, u32, u64, isize and usize can fail depending on the value and the platform, which is why all zval conversions are fallible.

Rust example

#![cfg_attr(windows, feature(abi_vectorcall))]
extern crate ext_php_rs;
use ext_php_rs::prelude::*;
#[php_function]
pub fn test_numbers(a: i32, b: u32, c: f32) -> u8 {
    println!("a {} b {} c {}", a, b, c);
    0
}
fn main() {}

PHP example

<?php

test_numbers(5, 10, 12.5); // a 5 b 10 c 12.5