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Clean code: extract until it reads
Principles · TypeScript
Clean code: extract until it reads
Turn a long function into named steps you can read from top to bottom.
10 steps
4 chapters
~4 min at 1.25×
#extract method
#long method
#readability
#split variable
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Every step
Problem
Steps 1–3
01
A checkout that works
Before
02
A discount in the wrong place
Code smell
03
Undo, then extract
Plan
Refactor
Steps 4–7
04
Pull out the guard
Extract Function
05
Pull out the subtotal
Extract Function
06
One name per meaning
Split Variable
07
Pull out delivery
Extract Function
Payoff
Step 8
08
The discount, in the right place
Payoff
Recap
Steps 9–10
09
Where we started, where we ended
Before / after
10
When to reach for it
Takeaways