furze 0.0.1

finite state transducers (fst) writen in rust
Documentation 
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use crate::builder::Builder;
use crate::bytes::Bytes;
use crate::decoder::Decoder;
use crate::error::FstResult;

pub struct FST<'a> {
    data: &'a [u8],
}

impl<'a> FST<'a> {
    pub fn build() -> Builder<Vec<u8>> {
        Builder::new(Bytes::new()) 
    }

    pub fn load(data: &'a[u8]) -> FST<'a> {
        Self { data: data }
    }

    pub fn find(&self, key: &[u8]) -> FstResult<u64> {
        let mut decoder = Decoder::new(&self.data);
        decoder.find(key)
    }

    pub fn near(&self, key: &[u8]) -> FstResult<u64> {
        let mut decoder = Decoder::new(&self.data);
        decoder.near(key)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    #[test]
    fn test_add_to_fst() {
        let mut builder = FST::build();
        builder.add("aa".as_bytes(), 1).unwrap();
        builder.add("bb".as_bytes(), 2).unwrap();
        builder.add("cc".as_bytes(), 7).unwrap();
        builder.add("zz".as_bytes(), 9).unwrap();
        builder.finish().unwrap();
        let fst = FST::load(builder.bytes());
        let res = fst.find("cc".as_bytes());
        match res {
            Ok(v) => println!("cc res:{}", v),
            Err(e) => println!("e:{}", e),
        }

        builder.reset();
        builder.add("11".as_bytes(), 1).unwrap();
        builder.add("22".as_bytes(), 2).unwrap();
        builder.add("33".as_bytes(), 7).unwrap();
        builder.add("44".as_bytes(), 9).unwrap();
        builder.finish().unwrap();
        let fst = FST::load(builder.bytes());
        let res = fst.find("cc".as_bytes());
        match res {
            Ok(v) => println!("cc res:{}", v),
            Err(e) => println!("e:{}", e),
        }

        let res1 = fst.find("33".as_bytes());
        match res1 {
            Ok(v) => println!("44 res:{}", v),
            Err(e) => println!("e:{}", e),
        }
    }
}