Consider the following code:

    #[test]
    fn foo() {
        const FOO: LazyCell<()> = LazyCell::new(|| eprintln!("init_FOO"));
        let bar: LazyCell<()> = LazyCell::new(|| eprintln!("init_bar"));
        LazyCell::force(&FOO);
        LazyCell::force(&FOO);
        LazyCell::force(&bar);
        LazyCell::force(&bar);
    }

I would expect running this test to print:

init_FOO
init_bar

However, I instead see:

init_FOO
init_FOO
init_bar

It appears that by moving the LazyCell to a global const, it stops working as expected, and instead recalls the initializer on every access.

My motivation for using LazyCell is to have the cell be a global to avoid repeating an expensive initailization call, and I don't think there is an easy way to accomplish that without making it const.

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