Reading assignment - auto variables

  • What is an auto variable?
    An auto variable it’s a variable whose type will be automatically deduced from its initializer.
  • Why is it convenient to use?
    It makes the code easy to write and comprehend. But we should avoid abuse.
  • When should you use it?
    When we need to cut down unnecessary typing of complex data types on the left hand.
  • When will the type of an auto variable be determined (compile-time or run-time?).
    It will be determined at compile time. Also the auto keyword forces the initialization of variables.
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  1. What is an auto variable?
  • No need to declare the type of variable beforehand, it will auto-detected the type.
  1. Why is it convenient to use?
  • no need to specific the variable type
  1. When should you use it?
    when we want to declare the type of variable after the initializer type is declared.
  2. When will the type of an auto variable be determined (compile-time or run-time?)
    compile time
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  1. What is an auto variable?
    Auto variable is a variable-type specifier that is not explicitely declared and it is dynamically assigned a data type (float, int, etc.).

  2. Why is it convenient to use?
    Makes working with C++ variables easier because you do not have to strictly say what type of variable you are working with. Once the type of the initializer has been determined, the compiler determines the type that will replace the keyword auto.

  3. When should you use it?
    Most useful when you are writing robust code that can handle different types of inputs. More specifically when working in a block scope or namespace scope.

  4. When will the type of an auto variable be determined (compile-time or run-time?)
    Compile time. Once the type of the initializer has been determined, the compiler determines the type that will replace the auto variable.

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  1. Auto Variables in C++ are used to automatically assign a type to the following variable name.
  2. It is convenient because it helps simplify the code by letting C++ compiler figure out the type of the variables.
  3. It may be used everywhere C++ compiler can clearly deduct the intended type and avoided when there might be ambiguity nor misunderstanding.
  4. Of course the compiler will check and find the appropriate type of the variable.
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  1. What is an auto variable?
    An auto variable is a variable that lets C++ decide what a datatype following the initialization. C++ will automatically decide if the variable is a string, int, or double etc based on what is initialized.

2.Why is it convenient to use?
Using the ‘auto’ specifier is convenient because it lets C++ do the deciding. Say we use auto for our variables and functions. If we were to change the data type of elements within the function, ‘auto’ would change the data type for us. This could be useful for things like changing a piece of the API, and if the client side code was using auto, they would not even notice the difference.

  1. When should you use it?
    We should use auto specifiers when we are sure that our code will not crash should there be a change in data type. Auto is convenient, but it could lead to some problems down the road if not used carefully.

  2. When will the type of an auto variable be determined (compile-time or run-time)?
    The type is determined during compile time, where the compiler will determine the type and replace it with the auto keyword.

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1.It is a variable whose type will be automatically deduced at compile time
2.Allows more flexibility to code
3.When you are unsure of the type of the variable that will be used.
4. The type of the auto variable will be determined at compile-time

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  1. An auto variable is one that will be automatically deduced from its initializer.

  2. It can be used when the value is not known beforehand. The compiler will automatically fill the missing gaps at once across multiple functions as needed.

  3. It gives flexibility with data that is entered and can later be changed.

  4. Compile-time.

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  1. What is an auto variable? auto variables specifies that the type of variable that is being declared, will be automatically deduced from its initializer.

  2. Why is it convenient to use? it saves the programmer time with type specification.

  3. When should you use it? When declaring variables, in block scope, in namespace scope, in initialization statements of for loops. etc.,

  4. When will the type of an auto variable be determined (compile-time or run-time?) The compiler determines the type.

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  1. A data type specifier that attempts to discern the necessary data type automatically
  2. Sometimes the data type of a return is uncertain, or perhaps a variable may need an int or string depending on a situation, etc.
  3. It should only be used when data type discernment is needed during compile time and the scenario calls for flexibility
  4. " Once the type of the initializer has been determined, the compiler determines the type that will replace the keyword auto" - so compile time.

1. What is an auto variable?
The auto variable uses the keyword “auto” to replace the type declaration. The type will be deduced from the variable initialization.
2. Why is it convenient to use?
You don’t have to determine the type of the variable in advance since c++ will deduce the type after initialization
3. When should you use it?
You can use it everywhere where it is possible that your operation can return different types. But only usable when you initialize a variable upon creation, because the initialization will cause the type deduction.
4. When will the type of an auto variable be determined (compile-time or run-time?)
It will be determined at compile-time

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  1. An auto variable is a variable that has its type deduced automatically from the expression by the initializer.
  2. Its convenient to use when you don’t know the data type of a variable.
  3. It should be use when you don’t know the type of variable that will be used.
  4. The type of an auto variable is determine at compile time or run time.
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  1. What is an auto variable?
    The type of variable is automaticly deduced from its initializer.

  2. Why is it convenient to use?
    When working with lengthy data type specifiers, where the intialisation expression for the variable is clear.

  3. When should you use it?
    When the data type is unknow at the moment.

  4. When will the type of an auto variable be determined (compile-time or run-time?)
    Compile-time

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  1. What is an auto variable? It is a variable of the type that’s automatically deduced from its initializer
  2. Why is it convenient to use? It is convenient because it saves time declaring different types of variables. You can use one specifier (auto) and initialize variables immediately.
  3. When should you use it? You may use it when there are many types of variables involved in your function. And to add to question 2, it may be convenient while you write code and unsure of what specific type the variable you’re using is. You can decide while initializing.
  4. When will the type of an auto variable be determined (compile-time or run-time?) It will be determined during compile time.
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  1. What is an auto variable?

    The type of the variable that is being declared will be automatically deduced from its initializer.

  2. Why is it convenient to use?

    Allows flexibility when you don’t know what the data type of the variable will be.

  3. When should you use it?

    When you don’t know what the data type of the variable will be.

  4. When will the type of an auto variable be determined (compile-time or run-time?)

    Compile-time

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  1. Keyword auto in front of a variable means the the type will be infered by the initializer.

  2. It allows the programmer to leave the type deduction to the compiler simplifying his/her life.

  3. When we want to shorten and simplify initializations

  4. Compile-time

1. What is an auto variable?

A Variable declared with auto, is a variable which type will be deduced from its initializer. Therefore, auto is not a datatype per se, but a stand-in for a data type that will be deduced. For example auto I = 0, we are asking the compiler to deduce the type of I, which from its initializer is an int. If we choose to declare several variables on the same line, for example auto I = 0, J = 0, the type of both variables much match, which they do in this example, they both are ints.

2. Why is it convenient to use?

Some data declaration are straightforward and can be written right off the bat. However sometimes declaring variables can be tricky and make a line of code verbose and unreadable. Using auto makes the code much easier to read and understand in those circumstances. Auto makes complex or templatized data types easy.

3. When should you use it?

As mentioned above, it is convenient to use to declare complex or templatized data types. It also makes iterator loops easier to write, and therefore read and understand. It also makes lambda expressions,which effectively store an unnamed function objects that capture a variable that can then be reused later.

4. When will the type of an auto variable be determined (compile-time or run-time?)

The type will be determine at compile-time

Hi @filip, Could I ask that you provide your version for these answers? Looking online I have to say that I am not sure I have fully grasped the concept, and the answers from this forum page differ widely also. thanks in advance for your answer.

Answers looks correct @TNP

  1. What is an auto variable?

A variable whose type is automatically deduced from its initializer (as opposed to being explicitly declared)

  1. Why is it convenient to use?

Auto variables reduce the unnecessary typing of complex data types on the left-side of the assignment operator and improve readability

  1. When should you use it?

Auto variables should be used for iterator variables

  1. When will the type of an auto variable be determined (compile-time or run-time?)

Auto variables are determined at compile-time.

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  1. What is an auto variable? An auto variable is one that uses the type setting of ‘auto’ (runs at compile time to determine what type of variable is being used based on what variable is being used during instantiation)
  2. Why is it convenient to use? This lets C++ do the work of determing the type of variable
  3. When should you use it? This is best used when the type of variable that might be passed in is unknown, or when the type is unusually complex.
  4. When will the type of an auto variable be determined (compile-time or run-time?) Compile time.
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  1. A variable that the type of variable that is being declared will be automatically be deduced from its initialiser

  2. It is convenient if the type of the variable is not known when the variable is being declared

  3. Auto variables should be used to improve readability of your code and can be used for storing lambda expressions when they need to be reused.

  4. Auto variables will be determined at compile-time

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