Source code
Revision control
Copy as Markdown
Other Tools
# icu_segmenter [](https://crates.io/crates/icu_segmenter)
<!-- cargo-rdme start -->
Segment strings by lines, graphemes, words, and sentences.
This module is published as its own crate ([`icu_segmenter`](https://docs.rs/icu_segmenter/latest/icu_segmenter/))
and as part of the [`icu`](https://docs.rs/icu/latest/icu/) crate. See the latter for more details on the ICU4X project.
This module contains segmenter implementation for the following rules.
- Line segmenter that is compatible with [Unicode Standard Annex #14][UAX14], _Unicode Line
Breaking Algorithm_, with options to tailor line-breaking behavior for CSS [`line-break`] and
[`word-break`] properties.
- Grapheme cluster segmenter, word segmenter, and sentence segmenter that are compatible with
[Unicode Standard Annex #29][UAX29], _Unicode Text Segmentation_.
## Examples
### Line Break
Find line break opportunities:
```rust
use icu::segmenter::LineSegmenter;
let segmenter = LineSegmenter::new_auto();
let breakpoints: Vec<usize> = segmenter
.segment_str("Hello World. Xin chào thế giới!")
.collect();
assert_eq!(&breakpoints, &[0, 6, 13, 17, 23, 29, 36]);
```
See [`LineSegmenter`] for more examples.
### Grapheme Cluster Break
Find all grapheme cluster boundaries:
```rust
use icu::segmenter::GraphemeClusterSegmenter;
let segmenter = GraphemeClusterSegmenter::new();
let breakpoints: Vec<usize> = segmenter
.segment_str("Hello World. Xin chào thế giới!")
.collect();
assert_eq!(
&breakpoints,
&[
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 21, 22, 23, 24, 25, 28, 29, 30, 31, 34, 35, 36
]
);
```
See [`GraphemeClusterSegmenter`] for more examples.
### Word Break
Find all word boundaries:
```rust
use icu::segmenter::WordSegmenter;
let segmenter = WordSegmenter::new_auto();
let breakpoints: Vec<usize> = segmenter
.segment_str("Hello World. Xin chào thế giới!")
.collect();
assert_eq!(
&breakpoints,
&[0, 5, 6, 11, 12, 13, 16, 17, 22, 23, 28, 29, 35, 36]
);
```
See [`WordSegmenter`] for more examples.
### Sentence Break
Segment the string into sentences:
```rust
use icu::segmenter::SentenceSegmenter;
let segmenter = SentenceSegmenter::new();
let breakpoints: Vec<usize> = segmenter
.segment_str("Hello World. Xin chào thế giới!")
.collect();
assert_eq!(&breakpoints, &[0, 13, 36]);
```
See [`SentenceSegmenter`] for more examples.
<!-- cargo-rdme end -->
## More Information
For more information on development, authorship, contributing etc. please visit [`ICU4X home page`](https://github.com/unicode-org/icu4x).