raqim-kashida 0.1.0

Kashida (tatweel) insertion-point finding driven by pattern sets.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43

//! The built-in pattern sets, compiled on first use.

use crate::pattern::{compile_pattern_text, PatternSet};
use std::sync::OnceLock;

const ARABIC_SIMPLE_TEXT: &str = include_str!("../data/arabic-simple.pat");
const ARABIC_NASKH_TEXT: &str = include_str!("../data/arabic-naskh.pat");
const SYRIAC_TEXT: &str = include_str!("../data/syriac.pat");

fn arabic_simple_set() -> &'static PatternSet {
    static SET: OnceLock<PatternSet> = OnceLock::new();
    SET.get_or_init(|| {
        compile_pattern_text(ARABIC_SIMPLE_TEXT).expect("built-in \"arabic-simple\" compiles")
    })
}

fn arabic_naskh_set() -> &'static PatternSet {
    static SET: OnceLock<PatternSet> = OnceLock::new();
    SET.get_or_init(|| {
        compile_pattern_text(ARABIC_NASKH_TEXT).expect("built-in \"arabic-naskh\" compiles")
    })
}

fn syriac_set() -> &'static PatternSet {
    static SET: OnceLock<PatternSet> = OnceLock::new();
    SET.get_or_init(|| compile_pattern_text(SYRIAC_TEXT).expect("built-in \"syriac\" compiles"))
}

/// Whether `name` refers to a built-in pattern set, without compiling it,
/// unlike [`builtin_pattern_set`].
pub fn is_builtin_pattern_set(name: &str) -> bool {
    matches!(name, "arabic-simple" | "arabic-naskh" | "syriac")
}

/// The built-in pattern set of that name.
pub fn builtin_pattern_set(name: &str) -> Option<&'static PatternSet> {
    match name {
        "arabic-simple" => Some(arabic_simple_set()),
        "arabic-naskh" => Some(arabic_naskh_set()),
        "syriac" => Some(syriac_set()),
        _ => None,
    }
}