Function accepts_encoding 

pub fn accepts_encoding(accept_encoding: &str, coding: &str) -> bool

Returns true if accept_encoding lists coding as an acceptable encoding.

Matches on comma/;-delimited token boundaries (so x-gzip does not match gzip) and treats an explicit q=0 as “not acceptable”. Shared by the accept_encoding and compression plugins so the two cannot disagree about what the client accepts.