2.18 Summary

In this chapter, we explored the basic structure and organization of Rust programs, highlighting both the similarities and differences with C. We covered:

  • Compilation and Cargo: How Rust compiles to an executable binary and how Cargo streamlines building and dependency management.
  • Program Structure: The default layout of Rust programs, including modules, functions, types, and use statements for namespacing.
  • main Function: Rust's entry point and how it compares to C's main.
  • Variables and Mutability: Rust's immutable-by-default approach and explicit mut keyword.
  • Data Types: Rust's clear, fixed-width numeric types, plus booleans and Unicode-based char.
  • Constants and Statics: How to declare compile-time constants and static variables.
  • Functions and Control Flow: Defining functions, using if, while, and for loops, and the unique loop construct.
  • Modules and Crates: Organizing code into modules, compiling it into binary or library crates.
  • use and Namespacing: Precisely importing items into scope, contrasting with C's preprocessor includes.
  • Traits: Abstracting shared behavior without resorting to function pointers or manual vtables.
  • Macros: Safe, flexible compile-time code generation beyond C's macro system.
  • Error Handling: Using Result and Option instead of exceptions or error codes.
  • Memory Safety: Ownership, borrowing, and how Rust prevents common memory errors at compile time.
  • Expressions vs. Statements: Rust's expression-based syntax and how it differs from C.
  • Style and Documentation: Conventions for naming, formatting, and writing documentation with rustdoc.
  • Async Support: Rust's async/await model and safe concurrency via crates like tokio.

Each of these elements contributes to Rust's goals of safety, performance, and concurrency. Understanding them lays a solid foundation for more advanced topics like ownership, lifetimes, and concurrent programming. The next chapters will delve deeper into these areas, showing how Rust's unique features further distinguish it from C and other systems languages.