Rust C-style for-loop

#![feature(macro_rules)]
macro_rules! cfor(
    ($($ident:ident = $pre:expr),*; $cond:expr; $($post:expr),*; $block:block) => ({
    	$( let mut $ident = $pre; )*
	while $cond {
	    $block
	    $( $post; )*
	}
    });
)

fn main() {
    cfor!(i = 0i, j = 1i; i < 5; i += 1, j += 2; {
        println!("Hello {} {}", i, j);
    })
}

Thank for your c loop in rust, it is very useful for me. To declare multiple mutable variables at the same time. Defined a macro to declare mutable variables as the following.

macro_rules! double {
    ( $($var:ident),+) => {
        $(let mut $var: f64;)+
    };
}

fn main() {
    double!(FT, FX, alpha, H, K, lambda, T, X);

    FT = 2.0;
    println!("{}", FT);
}