TypeScript Mid
What is an anonymous function in TypeScript?
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An anonymous function in TypeScript is a function that returns a boolean.
An anonymous function in TypeScript is a function declared with the var keyword.
An anonymous function in TypeScript is a function that does not have a name.
An anonymous function in TypeScript is a function with a static keyword.
Explain the as const assertion in TypeScript.
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The as const assertion in TypeScript ensures that the type of a value is a literal type.
The as const assertion in TypeScript converts a type to any.
The as const assertion in TypeScript is used to declare constants.
The as const assertion in TypeScript makes a variable immutable.
Explain the concept of "declaration files" in TypeScript.
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Declaration files in TypeScript provide type information about JavaScript libraries to TypeScript.
Declaration files in TypeScript are a way to define custom types.
Declaration files in TypeScript are used to configure the TypeScript compiler.
Declaration files in TypeScript are used for managing project dependencies.
Explain the purpose of the "key remapping" feature in mapped types in TypeScript.
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Key remapping in mapped types in TypeScript is a method for importing modules.
Key remapping in mapped types in TypeScript is a feature for handling asynchronous operations.
Key remapping in mapped types in TypeScript is used to define optional properties.
Key remapping in mapped types in TypeScript allows the keys of a type to be transformed during the creation of a new type.
What is the purpose of "string literal types" in TypeScript?
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String literal types in TypeScript are types that can hold any string value.
String literal types in TypeScript are used to define enum values.
String literal types in TypeScript are types whose value is a specific string.
String literal types in TypeScript are used to define string arrays.
What is "type-safe nullish coalescing" in TypeScript?
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Type-safe nullish coalescing in TypeScript ensures that null or undefined values are handled safely.
Type-safe nullish coalescing in TypeScript is a method for error handling.
Type-safe nullish coalescing in TypeScript is used for strict null checks.
Type-safe nullish coalescing in TypeScript converts all null values to empty strings.
What is meant by contextual typing?
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Contextual typing in TypeScript is the process of defining custom types.
Contextual typing in TypeScript is used to handle asynchronous programming.
Contextual typing in TypeScript is a feature for importing modules.
Contextual typing in TypeScript is the process by which the compiler infers types based on the context of the code.
What is the Omit utility type in TypeScript?
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The Omit utility type in TypeScript constructs a type by excluding certain properties from another type.
The Omit utility type in TypeScript makes all properties of a type optional.
The Omit utility type in TypeScript converts a type into a union type.
The Omit utility type in TypeScript is used to define arrays.
What is the Partial utility type in TypeScript?
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The Partial utility type in TypeScript is used to define arrays.
The Partial utility type in TypeScript makes all properties of a type optional.
The Partial utility type in TypeScript converts a type into a union type.
The Partial utility type in TypeScript removes all properties of a type.
What is the purpose of the unknown type in TypeScript?
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The unknown type in TypeScript represents a value that could be of any type but is more type-safe than any.
The unknown type in TypeScript is used exclusively for arrays.
The unknown type in TypeScript is used for variables that are null or undefined.
The unknown type in TypeScript is used for defining constants.
What is the purpose of noImplicitAny?
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The noImplicitAny flag in TypeScript allows the use of any type without errors.
The noImplicitAny flag in TypeScript ensures that all variables have an explicit type.
The noImplicitAny flag in TypeScript is used to enable strict null checks.
The noImplicitAny flag in TypeScript allows implicit casting between types.
Explain the purpose of type predicates in TypeScript.
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Type predicates in TypeScript are functions that return a boolean indicating the type of a variable.
Type predicates in TypeScript are used to declare types.
Type predicates in TypeScript are tools for debugging.
Type predicates in TypeScript are methods for importing modules.
Explain the concept of "recursive types" in TypeScript.
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Recursive types in TypeScript are types that reference themselves.
Recursive types in TypeScript are types that inherit from other types.
Recursive types in TypeScript are types that can be null or undefined.
Recursive types in TypeScript are types used for async functions.
What is the "non-nullable assertion operator" (!) in TypeScript?
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The non-nullable assertion operator (!) in TypeScript is used to import modules.
The non-nullable assertion operator (!) in TypeScript is used for creating loops.
The non-nullable assertion operator (!) in TypeScript is used to declare constants.
The non-nullable assertion operator (!) in TypeScript tells the compiler that a value is not null or undefined.
Explain the concept of discriminated unions in TypeScript.
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Discriminated unions in TypeScript are unions with a common property used to distinguish between them.
Discriminated unions in TypeScript are used to handle errors.
Discriminated unions in TypeScript are used to define enums.
Discriminated unions in TypeScript are used for asynchronous programming.
What are distributive conditional types?
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Distributive conditional types in TypeScript distribute a conditional type over a union type.
Distributive conditional types in TypeScript are used to define array types.
Distributive conditional types in TypeScript are a type of error handling.
Distributive conditional types in TypeScript are used for module imports.
What are "conditional types" in TypeScript?
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Conditional types in TypeScript allow for type selection based on a condition.
Conditional types in TypeScript are used to define enums.
Conditional types in TypeScript are a type of error handling.
Conditional types in TypeScript are used to create optional parameters.
What is the purpose of keyof in TypeScript
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The keyof keyword in TypeScript is used to get the keys of an object type.
The keyof keyword in TypeScript is used to declare dynamic properties.
The keyof keyword in TypeScript is used to import modules.
The keyof keyword in TypeScript is used to create new types.
What are mixins?
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Mixins in TypeScript are a type of module import.
Mixins in TypeScript are a way to manage state.
Mixins in TypeScript are a way to create reusable code by combining multiple classes.
Mixins in TypeScript are used to style components.
What is optional chaining in TypeScript?
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Optional chaining in TypeScript allows for the safe access of nested object properties.
Optional chaining in TypeScript is used to create optional function parameters.
Optional chaining in TypeScript is a method for error handling.
Optional chaining in TypeScript is used to declare optional variables.
What is void, and when to use the void type?
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Void in TypeScript represents a type that can be anything.
Void in TypeScript is used for error handling.
Void in TypeScript represents the absence of a return value from a function.
Void in TypeScript represents a null value.
How does TypeScript handle asynchronous programming?
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TypeScript handles asynchronous programming with only callback functions.
TypeScript handles asynchronous programming with a special async keyword.
TypeScript handles asynchronous programming with promises, async/await syntax, and observables.
TypeScript handles asynchronous programming by automatically converting all functions to async.
What are mapped types in TypeScript?
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Mapped types in TypeScript are used to manage project dependencies.
Mapped types in TypeScript create new types by transforming properties.
Mapped types in TypeScript are used to configure the TypeScript compiler.
Mapped types in TypeScript are used for mapping URLs to components.
What are intersection types in TypeScript, and how do they differ from union types?
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Intersection types in TypeScript combine multiple types into one.
Intersection types in TypeScript are used for asynchronous programming.
Intersection types in TypeScript are used to create read-only properties.
Intersection types in TypeScript are used to define numeric arrays.
What is a union type in TypeScript?
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A union type in TypeScript is a method for error handling.
A union type in TypeScript is a special type for handling numbers and strings together.
A union type in TypeScript is used for combining multiple interfaces.
A union type in TypeScript allows a variable to be one of several types.
What is the null and undefined type in TypeScript?
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In TypeScript, null and undefined are types used for error handling.
In TypeScript, null and undefined are types that represent boolean values.
In TypeScript, null and undefined are types that represent zero and empty string.
In TypeScript, null and undefined are types that represent the absence of a value.
What is strict mode in TypeScript?
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Strict mode in TypeScript is used for optimizing code performance.
Strict mode in TypeScript enables runtime type checking.
Strict mode in TypeScript is used to enforce strict naming conventions.
Strict mode in TypeScript is a set of type-checking options that ensure more robust code.
What is an enum in TypeScript.
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An enum in TypeScript is used to define environment variables.
An enum in TypeScript is a data type for storing arrays.
An enum in TypeScript is a syntax for creating classes.
An enum in TypeScript is a way of defining named constants.
Explain the never type in TypeScript.
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The never type in TypeScript represents values that never occur.
The never type in TypeScript represents null and undefined values.
The never type in TypeScript represents a type that can be anything.
The never type in TypeScript is used for declaring global variables.
Explain what tuples are TypeScript.
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Tuples in TypeScript are arrays with a fixed number of elements of specified types.
Tuples in TypeScript are functions that return multiple values.
Tuples in TypeScript are classes with multiple inheritance.
Tuples in TypeScript are objects with dynamic properties.
How can a class constant be implemented in TypeScript?
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A class constant can be implemented using the const keyword in TypeScript.
A class constant can be implemented using the static keyword in TypeScript.
A class constant can be implemented using the readonly keyword in TypeScript.
A class constant can be implemented using the private keyword in TypeScript.
What is a type guard in TypeScript, and how does it help narrow down types?
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A type guard is a debugging tool in TypeScript.
A type guard is a function that determines if a variable is of a specific type, helping to narrow down types in TypeScript.
A type guard is used to secure TypeScript applications from hacking.
A type guard is a syntax error detector in TypeScript.
Explain the difference between interface and type alias in TypeScript.
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Interfaces are used for styling components, and type aliases are used for database connections.
Interfaces are used for creating instances, and type aliases are used for importing modules.
Interfaces are used for managing state, and type aliases are used for routing.
Interfaces define a contract for a structure, whereas type aliases can define primitive types, union types, and tuples.
What are TypeScript decorators?
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TypeScript decorators are used to configure the TypeScript compiler.
TypeScript decorators are used to create private methods.
TypeScript decorators are used to style components.
TypeScript decorators are special types of declarations that can be attached to a class, method, accessor, property, or parameter.
What is the as keyword used for in TypeScript?
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The as keyword is used to create asynchronous functions.
The as keyword is used for type assertions in TypeScript.
The as keyword is used to declare static variables.
The as keyword is used to import modules.
What is the any type in TypeScript, and when should you use it?
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The any type in TypeScript is used for functions returning strings.
The any type in TypeScript is used exclusively for numbers.
The any type in TypeScript is used to declare arrays only.
The any type in TypeScript is used when you want to disable type checking for a variable.