Struct Decoder 

pub struct Decoder<'huff, ValueType, D = BitsPerFragment> { /* private fields */ }

Decoder that decodes a value for given code, consuming one codeword fragment (and going one level down the huffman tree) at a time.

Time complexity of decoding the whole code is:

• pessimistic: O(length of the longest code)
• expected: O(log(number of values, i.e. length of coding.values))
• optimistic: O(1)

Memory complexity: O(1)

Implementations

impl<'huff, ValueType, D: TreeDegree> Decoder<'huff, ValueType, D>

pub fn new(coding: &'huff Coding<ValueType, D>) -> Self

Constructs decoder for given coding.

pub fn reset(&mut self)

Resets self to initial state and makes it ready to decode next value.

pub fn consumed_fragments(&self) -> u32

Returns the number of fragments consumed since construction or last reset.

pub fn consume(&mut self, fragment: u32) -> DecodingResult<&'huff ValueType>

Consumes a fragment of the codeword and returns:

• a value if the given fragment finishes the valid codeword;
• an DecodingResult::Incomplete if the codeword is incomplete and the next fragment is needed;
• or DecodingResult::Invalid if the codeword is invalid (possible only for bits per fragment > 1).

Result is undefined if fragment exceeds tree_degree.

pub fn consume_checked( &mut self, fragment: u32, ) -> DecodingResult<&'huff ValueType>

Consumes a fragment of the codeword and returns:

• a value if the given fragment finishes the valid codeword;
• an DecodingResult::Incomplete if the codeword is incomplete and the next fragment is needed;
• or DecodingResult::Invalid if the codeword is invalid (possible only for degree greater than 2) or fragment is not less than degree.

pub fn decode<F: Into<u32>, I: Iterator<Item = F>>( &mut self, fragments: &mut I, ) -> DecodingResult<&'huff ValueType>

Tries to decode and return a single value from the fragments iterator, consuming as many fragments as needed.

To decode the next value, self must be reset first (see also Self::decode_next).

In case of failure, returns:

• DecodingResult::Incomplete if the iterator exhausted before the value was decoded (Self::consumed_fragments enables checking if the iterator yielded any fragment before exhausting).
• DecodingResult::Invalid if obtained invalid codeword (possible only for degree greater than 2).

pub fn decode_next<F: Into<u32>, I: Iterator<Item = F>>( &mut self, fragments: &mut I, ) -> DecodingResult<&'huff ValueType>

Tries to decode and return a single value from the fragments iterator, consuming as many fragments as needed.

If successful, it resets self to be ready to decode the next value (see also Self::decode).

In case of failure, returns:

• DecodingResult::Incomplete if the iterator exhausted before the value was decoded (Self::consumed_fragments enables checking if the iterator yielded any fragment before exhausting).
• DecodingResult::Invalid if obtained invalid codeword (possible only for degree greater than 2).