theory stuff

examples/branches.rs

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+fn main() {
+    let number = 10;
+
+    if number < 5 {
+        println!("condition was true");
+    } else {
+        println!("condition was false");
+    }
+}

examples/datatypes.txt

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+Scalar types:
+- A scalar type represents a single value.
+- Integers:
+  - unsigned: (u8, u16, u32, u64, u128, usize) 
+  - signed: (i8, i16, i32, i64, i128, isize)
+  - defaults to u32
+  - usize/isize change automatically depending on CPU architecture
+- Floating point:
+  - f32, f64
+  - defaults to f64
+- Booleans:
+  - true/false
+- Char:
+  - Defined with '' as opposed to "" (which are used for strings)
+  - Can store unicode characters
+
+Compound types:
+- Compound types can group multiple values into one type. 
+  Rust has two primitive compound types: tuples and arrays.
+- Tuple:
+  - A tuple is a general way of grouping together a number of values with a variety of types into 
+   one compound type. Tuples have a fixed length: once declared, they cannot grow or shrink in size.
+  - We create a tuple by writing a comma-separated list of values inside parentheses. 
+    Each position in the tuple has a type, and the types of the different values in the tuple don’t 
+    have to be the same. 
+
+    okay i cant be bothered typing more: https://doc.rust-lang.org/stable/book/ch03-02-data-types.html
+
+- Arrays:
+  - defined with square brackets []
+  - all elements must be of the same type
+  - fixed length
+  - Arrays are defined like so:
+    - let a: [i32; 5] = [1, 2, 3, 4, 5];
+      - the first square brackets contain the type and the length
+  - Array elements are fetched by using the index of the object a[0] = 1, a[1] = 2, etc
+  

examples/datatypes_operations.rs

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+fn main() {
+    // addition
+    let sum = 5 + 10;
+
+    // subtraction
+    let difference = 95.5 - 4.3;
+
+    // multiplication
+    let product = 4 * 30;
+
+    // division
+    let quotient = 56.7 / 32.2;
+
+    // remainder
+    let remainder = 43 % 5;
+}

examples/functions.txt

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+https://doc.rust-lang.org/stable/book/ch03-03-how-functions-work.html
+
+- Rust uses snake case as the standard style for variable and funtion names (like_this)
+- Arguments in rust functions require that you specify the type
+  - Example:
+    - fn main() {
+        another_function(5);
+      }
+
+      fn another_function(x: i32) {
+        println!("The value of x is: {}", x);
+      }
+- Expressions dont end with semicolons
+- Functions automatically return the last line in them as the return value
+- The value of the return value is specified like so:
+  - fn five() -> i32 {
+        5
+    }
+- You can use a return statement to return early

examples/loop_return_value.rs

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+fn main() {
+    let mut counter = 0;
+
+    let result = loop {
+        counter += 1;
+
+        if counter == 10 {
+            break counter * 2;
+        }
+    };
+
+    println!("The result is {}", result);
+}