Meta Programming - Bangalore Ruby Users Group - July '18 meetup

In this presentation I talk about a particular problem statement and how I solved it using meta programming.

Transcript

1. def meta_programming
2. PROBLEM STATEMENT
3. 1.Many key-value pairs 2.Be easy to modify 3.Both single and multiple select 4.SQL query friendly 5.DB should be consistent with views
4. SOLUTIONS?
5. DATA V/S CODE
6. TAGS
7. 1.Many key-value pairs 2.Be easy to modify 3.Both single and multiple select 4.SQL query friendly 5.DB should be consistent with views TAGS
8. ENUM, NOT TEXT
9. config/locales/en.yml THE SINGLE SOURCE OF TRUTH
10. 1.Many key-value pairs 2.Be easy to modify 3.Both single and multiple select 4.SQL query friendly 5.DB should be consistent with views THE SINGLE SOURCE OF TRUTH
11. WHERE IS THE CODE? class Portfolio def gender # ... end def gender=(value) # ... end
12. THE MAGIC.
13. - Meta Programming PROGRAMS THAT WRITE PROGRAMS ” “
14. - Meta Programming A programming technique in which computer programs have the ability to treat programs as their data. ” “
15. FROM DATA TO CODE I18n.t('single_select').each do |key, value| # ... end I18n.t('multiple_select').each do |key, value| # ... end
16. define_method key do |arg = {}| # ... end define_method (key.to_s + '=').to_sym do |arg| # ... end FROM DATA TO CODE
17. 1.Many key-value pairs 2.Be easy to modify 3.Both single and multiple select 4.SQL query friendly 5.DB should be consistent with views PROBLEM SOLVED
18. SEEMS SO WRONG, YET SO RIGHT
19. — Rails Doctrine Ruby includes a lot of sharp knives in its drawer of features. Not by accident, but by design. ” “
20. SHARP KNIVES Code like: 2.days.ago is pure joy
21. SOURCE https://medium.com/m/865039e468d4
22. end @vedantsopinions @vedantsopinions