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Guilherme Mazui

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What is the Difference Between Actual and Formal Parameters?

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The main difference between actual and formal parameters lies in their usage and declaration within a function.

Actual Parameters:

  1. Actual parameters are the values or variables that are passed to a function when it is called.
  2. They can be constant values, variable names, or even expressions.
  3. Actual parameters are used in the function call and are also known as arguments.
  4. There is no requirement to define the data type for actual parameters.

Formal Parameters:

  1. Formal parameters are the variables declared in the function definition that accept the values passed to the function.
  2. They are always variables with a specified data type.
  3. Formal parameters are used in the function declaration and are also known as function parameters or function arguments.
  4. It is mandatory to define the data type of the receiving value for formal parameters.

In summary, actual parameters are the values passed to a function when it is called, while formal parameters are the variables declared in the function definition that accept the values passed to the function. Actual parameters can be constant values, variable names, or expressions, whereas formal parameters are always variables with a specified data type.

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  • What is the Difference Between Actual and Formal Parameters?
  • Comparative Table: Actual vs Formal Parameters

    • Comparative Table: Actual vs Formal Parameters

    The difference between actual and formal parameters lies in their usage and declaration within a function or subroutine. Here is a table summarizing the key differences:

    Actual Parameters Formal Parameters
    Actual parameters are the values passed when invoking a function or subroutine. Formal parameters are declared in the function or subroutine definition, and they act as placeholders for the actual parameters.
    Actual parameters can be constant values or variable names. Formal parameters can be treated as local variables of a function in which they are used.
    Actual parameters are defined in the calling function. Formal parameters are defined in the called function.
    In most cases, actual parameters are specified in a function call. Formal parameters are usually declared with their data types when defining the function.
    Actual parameters are passed from the calling function to the called function. Formal parameters are not passed but act as placeholders for the actual parameters passed from the calling function.
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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.