Typing Functions
Annotate parameters and the return type. Parameters are the most important place to write types.
Exampletypescript
Calling a function with the wrong argument types or count is an error.
Exampletypescript
Quick check
What does `: number` after the parameter list describe?
Your turn: write the code
Write a function area(w: number, h: number): number that returns width times height, then print area(3, 4).
Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.
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