Constant Value Argument Types

[AjaniBilby]

This would not affect the type signature but instead allows more condensed code to be written and the compiler to remove unnecessary clones.

Example of somewhat condensed code

class String {

    fn Length(this: #String): u64 {
        return this.size - cast#[u64](1);
    }

    fn Clone(this: #String): String {
        // Initiliase the data structure
        let out = Blank#[String]();
        out.data = Memory.Alloc(this.size);
        out.size = this.size;

        // Copy the blob data to the new allocation
        Memory.Copy($out.data, $this.data, this.size, false);

        return out;
    }
}

fn puts(str: #String) {
    puts(str.data);
}