The Ministry of Truth Rules for Good Software Design

A reworking of a lightning talk presentation first made by Allen Short at PyCon 2012

Transcript

1. The Ministry of Truth Rules for Good Software Design
2. PRINCIPLES OF GOOD OBJECT DESIGN Principles of good software design are
3. War is Peace
4. AS ATTACKS Treat all inputs
6. IS NOT BROKEN BY BAD INPUT A good interface
7. throw {! name: ”Bad Input Error”,! message: ”Oh noes!”! }! !
8. Freedom is Slavery
9. THE MORE FREEDOM YOU HAVE TO ACT The more you constrain your code’s behaviour,
10. run();! !
11. AND IT IS SECURE.” “There is only one mode,
12. Ignorance is Strength
13. THINGS THEY NEED TO DO THEIR JOBS Only give objects access to the
14. To write better objects… •  Leave your object in a consistent state regardless of what your clients do. •  Prevent clients from accessing things they aren't supposed to touch. •  Only give your objects access to the resources they need to get the job done.
15. To write better programs… •  Leave your program in a consistent state regardless of what your clients do. •  Prevent clients from accessing things they aren't supposed to touch. •  Only give your programs access to the resources they need to get the job done.
16. Thanks This lightning talk was originally by Allen Short and was presented at PyCon 2012