zerotrie/builder/
litemap.rs

1// This file is part of ICU4X. For terms of use, please see the file
2// called LICENSE at the top level of the ICU4X source tree
3// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
4
5//! Impls for functions gated on the "litemap" feature.
6
7use super::konst::*;
8use crate::builder::bytestr::ByteStr;
9use crate::error::ZeroTrieBuildError;
10use crate::zerotrie::ZeroTrieSimpleAscii;
11use crate::ZeroTrie;
12use alloc::borrow::Borrow;
13use alloc::vec::Vec;
14use litemap::LiteMap;
15
16impl ZeroTrieSimpleAscii<Vec<u8>> {
17    #[doc(hidden)]
18    pub fn try_from_litemap_with_const_builder<'a, S>(
19        items: &LiteMap<&'a [u8], usize, S>,
20    ) -> Result<Self, ZeroTrieBuildError>
21    where
22        S: litemap::store::StoreSlice<&'a [u8], usize, Slice = [(&'a [u8], usize)]>,
23    {
24        let tuples = items.as_slice();
25        let byte_str_slice = ByteStr::from_byte_slice_with_value(tuples);
26        ZeroTrieBuilderConst::<10000>::from_sorted_const_tuple_slice::<100>(byte_str_slice.into())
27            .map(|s| Self {
28                store: s.as_bytes().to_vec(),
29            })
30    }
31}
32
33impl<K, S> TryFrom<&LiteMap<K, usize, S>> for ZeroTrie<Vec<u8>>
34where
35    // Borrow, not AsRef, because we rely on Ord being the same. Unfortunately
36    // this means `LiteMap<&str, usize>` does not work.
37    K: Borrow<[u8]>,
38    S: litemap::store::StoreSlice<K, usize, Slice = [(K, usize)]>,
39{
40    type Error = ZeroTrieBuildError;
41    fn try_from(items: &LiteMap<K, usize, S>) -> Result<Self, ZeroTrieBuildError> {
42        let byte_litemap = items.to_borrowed_keys::<[u8], Vec<_>>();
43        let byte_slice = byte_litemap.as_slice();
44        let byte_str_slice = ByteStr::from_byte_slice_with_value(byte_slice);
45        Self::try_from_tuple_slice(byte_str_slice)
46    }
47}
48
49// TODO(MSRV 1.83): Make this more infallible by calculating the required length,
50// heap-allocating the required capacity, and pointing ConstAsciiTrieBuilderStore
51// to the heap buffer.
52// ```
53// const fn write_to_mut_buffer(buf: &mut [u8]) { buf[0] = 0; }
54// ```
zerotrie/builder/litemap.rs

zerotrie/builder/
litemap.rs
