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Nathan Froyd
8d01bc5e88
Rust's default slices are convenient, but for tables like:
const f: &'static [(char, &'static [char])]
they take up far too much space. An element of the above array consumes
24 bytes on 64-bit platforms, and unicode-normalization contains about
6000 such array elements.
A better approach is to manually store a smaller slice type:
struct Slice {
offset: u16,
length: u16,
}
const f: &'static [(char, Slice)]
and store the actual character data in a separate array on the side.
The `Slice` structures then point in to this separate array, but at a
much smaller space cost: elements of the modified `f` take up only 8
bytes on 64-bit platforms, which implies a space savings of ~96K on
64-bit platforms. On some systems, this strategy also eliminates the
necessity of run-time relocations, which can be a further, significant
savings in binary size and runtime cost.
This change is strictly local to the library; it does not affect the
public API.
Unicode character composition and decomposition utilities as described in Unicode Standard Annex #15.
extern crate unicode_normalization;
use unicode_normalization::char::compose;
use unicode_normalization::UnicodeNormalization;
fn main() {
assert_eq!(compose('A','\u{30a}'), Some('Å'));
let s = "ÅΩ";
let c = s.nfc().collect::<String>();
assert_eq!(c, "ÅΩ");
}
crates.io
You can use this package in your project by adding the following
to your Cargo.toml:
[dependencies]
unicode-normalization = "0.1.3"