[IMPL] implement io functions

[Doomsk]

Implementation description

Just like #86 but this issue is intended to encompass the input/output (io) implementation. It may be further organized as sub-modules in the future, but for now, the bare minimum is needed, such as:

• writing function
  • files
  • buffers
• reading function
  • files
  • buffers

This may also involve creating types, constants, modifiers and other features to it.

Expected behavior

Description of particular implementations to be described below.