Conditional Types

Conditional types help in expressing types in relation to other types, particularly in generic types. It has the syntax T extends U ? X : Y.

type TypeName<T> = 
    T extends string ? "string" :
    T extends number ? "number" :
    T extends boolean ? "boolean" :


Define a type function IsString<T> that checks if a given type is string. If it is, it should return "Yes", otherwise "No".

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