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Basic Types 2 - Coggle Diagram

- - - - let combinedValues: any
      - could set it to any type
        
        combinedValues = 5
        
        and get a runtime error
  - - - a TypeScript type
        
        let combinedValues: Function
      - but doesn't specify
        
        paratmeter types
        
        function return type
    - - function types
      - let combinedValues: (a: number, b: number) => number
- - - - without error
    - - let userName: string userName = userInput
        
        gives a compilation error
        
        Type 'unknown' is not assignable to type 'string'
        
        you would have to insert a type check
        
        if (typeof userInput === 'string') { userName = userInput }
        
        but at least the warning alerts you to the need
      - you get more type checking with unknown
      - if userInput was of type any
        
        there would be no error
        
        because any disables all type checking