RDY DRY - functions, aspects, macros to the help

#presentation

- What is DRY
    - Do not repeat yourself
        - Do we really know when we repeat ourselves?
- Why DRY is important
    - We may fix code in one part forgetting of duplicated part
    - Wasted time on duplicating structures
    - No process for distilling our model
- Examples of DRY violation
    - standard duplication of code
        - three random examples
    - structure duplication (left - duplicated code, right - unduplicated)\
        - for converted to map
            - functional: map
        - measuring time of function
            - objectional: decorator
            - functional: lambda (high order function)
            - aspectional: aspect 
        - Database Transaction
            - aspectional: @Transactional
        - Function composition
            - |> macro: elixir