Feature renderable filter

[markzporter]

Work in progress PR for improving control character handling in the rendered output.

Implements:
#44

[alexrutar]

Just a general comment, you can use cargo fmt to avoid having to manually format things.

[alexrutar]

If you want to be able to run example files, you also need to edit Cargo.toml

[alexrutar]

You don't have to return a Vec here, you can return impl Iterator<Item = char> to the same effect:

fn control_chars() -> impl Iterator<Item = char> {
    (0x00..=0x1F).map(|i| char::from_u32(i).unwrap())
}

and the code should still compile. The reason is that for looks in rust are actually based on Iterators: the thing you are looping over is anything that implements the IntoIterator trait. The lazy version is better since it saves on an allocation.

[alexrutar]

The impl ... return type says "I am returning a concrete type, but I am just not telling you exactly what it is"; it's not actually a dynamic object. The compiler will replace your impl ... block with the actual type of the thing that you return.

[alexrutar]

Even better, you can directly construct a Range<char>:

const ASCII_CONTROL: Range<char> = '\x00'..='\x1F';

and just use that instead (since Range<char> implements IntoIterator<Item = char>).

[markzporter]

Right so the idea being that we are only storing one char in memory at a time OK makes sense. Will make this change thanks!

[markzporter]

If you want to be able to run example files, you also need to edit Cargo.toml

Interestingly, I am able to run the example without this. But will add it nonetheless

[alexrutar]

If you want to be able to run example files, you also need to edit Cargo.toml

Interestingly, I am able to run the example without this. But will add it nonetheless

Interesting! In my setup I can't even get syntax highlighting without including it as an example explicitly because rust analyzer complains that it isn't included in the project.