Introduction to Modules link

• What Are Modules?
  • Modules are a collection of items that can contain structs, functions, enums, vectors, arrays, etc.

💡Why make a module?

• As a result of making modules,
  • the program code becomes organized.
  • you can use the same name for things like a struct. For example, you can use the name Configuration in different modules and code it differently. Otherwise, you would have different clumsy names for the struct like EngineConfiguration, ConsoleConfiguration etc.

Declare a Module link

To declare a module in Rust use the mod keyword followed by the name of the module and the body of the module within curly braces { }.

• Naming Convention
  • Name of the module should be written in snake_case.

Invoking a Module link

The module can be invoked from anywhere within the program code.

Keywords for Modules link

• The following keywords are used for declaring modules:
  • mod - declares a new module
  • pub - makes a public module
  • use - imports the module in the local scope

Note: Modules are declared by the mod keyword and are private by default.

Example link

The following example makes use of the mod keyword to declare a module named r, and defines a function print_statement within the module:

  // declare a module

mod r {

  fn print_statement(){

    println!("Hi, this a function of module r");

  }

}

// main function

fn main() {

  // invoke a module 'r'

   r::print_statement();

}
  

The above code generates an error, ❌, because the function print_statement is private