Function compress_to_vec 

pub fn compress_to_vec<R: Read>(source: R, level: CompressionLevel) -> Vec<u8> 

Convenience function to compress some source into a Vec without reusing any resources of the compressor.

This helper eagerly buffers the full input (Read) before compression so it can provide a source-size hint to the one-shot encoder path. Peak memory can therefore be roughly input_size + output_size. For very large payloads or tighter memory budgets, prefer streaming APIs such as StreamingEncoder.

use structured_zstd::encoding::{compress_to_vec, CompressionLevel};
let data: &[u8] = &[0,0,0,0,0,0,0,0,0,0,0,0];
let compressed = compress_to_vec(data, CompressionLevel::Fastest);