You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: lib.rs
    path of file: ./repos/Theseus/kernel/framebuffer_compositor/src
    
    the code of the file until where you have to start completion: //! This crate defines a framebuffer compositor.
//!
//! A framebuffer compositor composites a list of framebuffers into a single destination framebuffer.
//! The coordinate system within a framebuffer is expressed relative to its origin, i.e., the top-left point.
//!
//! # Cache
//! The compositor caches groups of framebuffer rows for better performance. 
//!
//! First, it divides each framebuffer into ranges of rows called "blocks" which are `CACHE_BLOCK_HEIGHT` rows in height,
//! and deals with these row ranges one by one. 
//! The 
    
    fn is_cached<P: Pixel>(&self, row_pixels: &[P], dest_coord: &Coord, width: usize) -> bool {
        match self.caches.get(dest_coord) {
            Some(cache) => {
                // The same hash and width means the cache block is identical to the row pixels.
                // We do not check the height because if the hashes are the same, the number of pixels, namely `width * height` must be the same.
                cache.content_hash == hash(row_pixels) && (cache.block.bottom_right.x - cache.block.top_left.x) as usize == width
            }
            None => false
        }
    }