langram 0.5.2

Natural language detection library
Documentation 
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use crate::NgramSize;
use ahash::AHashSet;
use arraystring::{typenum::U20, ArrayString};
use debug_unsafe::arraystring::ArrayStringFrom;

pub(crate) type NgramString = ArrayString<U20>;

pub(crate) fn prepare_ngrams<'a>(
    words: impl Iterator<Item = &'a [char]>,
    ngram_size: NgramSize,
) -> Vec<NgramString> {
    let mut ngrams_tmp = AHashSet::new();
    let mut ngrams = Vec::new();

    for word in words {
        for ngram in word.windows(ngram_size as usize + 1) {
            if ngrams_tmp.insert(ngram) {
                ngrams.push(NgramString::from_chars_safe_unchecked(
                    ngram.iter().copied(),
                ));
            }
        }
    }

    ngrams
}

#[cfg(test)]
mod tests {
    use super::NgramString;
    use crate::ngram_size::NGRAM_MAX_LEN;

    #[test]
    fn test_ngram_string_size() {
        let max_ngram = [char::MAX; NGRAM_MAX_LEN];
        NgramString::try_from_chars(max_ngram).unwrap();
    }
}