nice-assert-no-alloc 1.0.0

Custom Rust allocator allowing to temporarily disable memory (de)allocations for a thread. Aborts or prints a warning if allocating although forbidden.
Documentation 
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use nice_assert_no_alloc::*;

#[cfg(debug_assertions)]
#[global_allocator]
static A: AllocDisabler = AllocDisabler;

fn main() {
    println!("Alloc is allowed. Let's allocate some memory...");
    let mut vec_can_push = Vec::new();
    vec_can_push.push(42);

    println!();

    let fib5 = assert_no_alloc(|| {
        println!("Alloc is forbidden. Let's calculate something without memory allocations...");

        fn fib(n: u32) -> u32 {
            if n <= 1 {
                1
            } else {
                fib(n - 1) + fib(n - 2)
            }
        }

        fib(5)
    });
    println!("\tSuccess, the 5th fibonacci number is {}", fib5);
    println!();

    assert_no_alloc(|| {
        println!("Alloc is forbidden. Let's allocate some memory...");
        let mut vec_cannot_push = Vec::new();
        vec_cannot_push.push(42); // panics
    });

    println!("This will not be executed if the above allocation has aborted.");
}