Optional, Default and Rest Parameters
Mark a parameter optional with ?, give it a default with =, or collect extras with ...rest.
Exampletypescript
An optional parameter can be undefined, so TypeScript makes you handle that before using it as a plain value.
Exampletypescript
Quick check
What does `...nums: number[]` allow?
Your turn: write the code
Write greet(name: string, greeting = "Hello"): string returning greeting, name. Print greet("Ada") and greet("Sam", "Hi").
Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.
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