Fix fixed-hash

[koushiro]

Signed-off-by: koushiro koushiro.cqx@gmail.com

Fix the problem that the current version of fixed-hash cannot be defined in constant directly.

related issue link: #109

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[koushiro]

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[niklasad1]

Hey,

Technically this is added functionality but it should be backwards compatible right?

Lastly, please respect the .editorconfig and we are not using cargo fmt please revert that commit

EDIT:
Well const fns doesn't look to be stable anytime soon so I guess that this make sense. We should probably add a tracking issue for that

However, if we merge this and switch back it is a breaking change just saying.

[Robbepop]

I like small PRs. Looks good to me and might help as long as there is no stable support for const-fn.

[larsrh]

Very much in favour of this. Without this change, the storage_keys! macro breaks.

[Robbepop]

Very much in favour of this. Without this change, the storage_keys! macro breaks.

Glad that you pointed this out!
However, on the other side the fix for storage_keys seems to be simple.

[larsrh]

The way I'm working around this right now looks as follows:

pub struct Key {
    pub key: [u8; 32]
}

impl Key {
    pub fn new(key: [u8; 32]) -> Key {
        Key { key: key }
    }

    pub fn h256(&self) -> H256 {
        H256::from(self.key)
    }
}

#[macro_export]
macro_rules! storage_keys {
	() => {};
	($($name:ident),*) => {
		storage_keys!(0u8, $($name),*);
	};
	($count:expr, $name:ident) => {
		static $name: Key = Key { key: [$count, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0] };
	};
	($count:expr, $name:ident, $($tail:ident),*) => {
		static $name: Key = Key { key: [$count, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0] };
		storage_keys!($count + 1u8, $($tail),*);
	};
}

Essentially, I'm building my own key type for storage.

[Robbepop]

I ll merge it as soon as CI is okay with it.
The current CI reports an issue with Windows but it doesn't look right so I just restarted it.

[bkchr]

@Robbepop travis windows is always broken and after they kicked out all people, it will probably never work.