Introduction to Rust

AtCoder with Rust RustCoder ―― Introduction to Competitive Programming with AtCoder and Rust

• Rust’s Functional Programming Language-like features
  • Is it something like let x = if ~~~?
  • The default is immutable, and even if it’s mutable, there are various constraints
    • It aims to be close to Referential Transparency…?

/villagepump/Rustlings

• Interesting (blu3mo)

Rust Links Collection - Qiita

Rust Tour - Let’s go on an adventure!

• As a starting point

• let cannot be changed unless it’s mut

  • But can it be redeclared?

• usize, isize

  • The index of an array is usize

• There are arrays and slices, right?

  • Whether they are fixed-length or not
  • Arrays are like a version of tuples with n elements

• No Null in Rust

• If, match, functions, and blocks without ; at the end are used as return values. This is the best way to create concise logic that returns a value, which can be assigned to a new variable.

• Memory space

• Rust’s Error

  • do_something_that_might_fail(432)?
    • If an Error is returned, it becomes return Err(e)
  • If do_something_that_might_fail(432) is executed in main(), main will return with an error and exit

• Vec

  • Similar to C++‘s vector
  • The vector struct holds a reference to Heap Memory

• Macro

  • println! and vec! are macros, right?

• Ownership in Rust

• Lifetimes

  • I understand that it refers to the period from creation to dropping
  • However, I can’t quite grasp lifetime specifiers
    • I thought lifetimes were determined by the content of the program, but can they be set artificially? Is it okay to have contradictions?
  • The static lifetime, like static variables, lasts until the end of the program
    • Does it mean it is placed in Data Memory?

• Impressions

  • I quite like it
    • It feels clean
    • It seems to aim to do things with fewer essential elements, which is beautiful (?)
  • The constraints around ownership and writing asynchronous code seem difficult

• Steps to Set Up a Local Rust Development Environment on macOS 2022 - Qiita