glz::reader/glz::writer for incremental reading/writing #1019
Description
Glaze doesn't easily support incremental reading and writing. There are times when we want to just parse the first element of an array, perform logic in our program, and then decide how what item to use to parse the rest of the array. This is common for formats that need header information.
Another use case is appending data to a buffer incrementally.
This issue proposes the addition of two stateful classes: gz::reader and glz::writer, which will enable incremental reading/writing.
Initially this will focus on array support, but object support will be considered in the design.
Example syntax:
glz::reader reader{buffer};
reader.read(glz::element<0>(value));
reader.read(glz::rest(value));glz::writer writer{buffer};
writer.append(value);
write.append(value);