Repo for learning Rust
To compile: rustc main.rs
Build using cargo:
in the directory, run cargo build
this creates the runnable file, which can be run using ./target/debug/(filecreated)
cargo run can be used to build and run the program in one command
to check the code compiles, run cargo check
cargo build --release creates a file in /releases and includes optimizations to make the rust code run faster
integers, floating-point numbers, booleans and characters
integer has multiple lengths, e.g. 8bit, 16bit, 32bit, 64bit, 128bit and arch
they come in two types of signed and unsigned, unsigned means it will only ever be positive.
e.g.:
So an i8 can store numbers from -(27) to 27 - 1, which equals -128 to 127. Unsigned variants can store numbers from 0 to 2n - 1, so a u8 can store numbers from 0 to 28 - 1, which equals 0 to 255.
Number literals can also use _ as a visual separator to make the number easier to read, such as 1_000, which will have the same value as if you had specified 1000.
Number literals Example
Decimal 98_222
Hex 0xff
Octal 0o77
Binary 0b1111_0000
Byte (u8 only) b'A'
f32 or f64, f64 is default if not stated
represented by bool
let c = 'z';
let heart_eyed_cat = '😻';
tuples and arrays
once declared, have fixed length
let tup: (i32, f64, u8) = (500, 6.4, 1);
Access values using pattern matching
let tup = (500, 6.4, 1);
let (x, y, z) = tup;
println!("The value of y is: {}", y);z
Or use a dot operator with the index of the value
let x: (i32, f64, u8) = (500, 6.4, 1);
let five_hundred = x.0;
let six_point_four = x.1;
let one = x.2;
Every element of an array must have the same type, they also have a fixed length once declared.
Vectors can change size and is similar to array.
To write the type, use square brackets:
let a: [i32; 5] = [1, 2, 3, 4, 5];
Initialise all elements with the same value:
let a = [3; 5]; is the same as let a = [3, 3, 3, 3, 3]; but in a more concise way.
let a = [1, 2, 3, 4, 5];
let first = a[0]; // 1
there are three types of loops:
loop, while and for