Rust-basic-methods.md

Rust Basic Methods

A small reference for the most common methods.

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Vec<T> Description:

• vec.push(value) Add one item to the end.
• vec.pop() Remove the last item.
• vec.remove(index) Remove one item by index.
• vec.len() Number of items.
• vec.first() First item.
• vec.last() Last item.
• vec.iter() Read all items with Borrow,Doesn't take Ownership.

Example

let mut vec = vec![1, 2, 3];

vec.push(4);
vec.pop();
vec.remove(0);

println!("{}", vec.len());
println!("{:?}", vec.first());
println!("{:?}", vec.last());

for item in vec.iter() {
    println!("{}", item);
}

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String Description:

• text.push('A') Add one char.
• text.push_str("Ali") Add one string.
• text.trim() Remove spaces at start and end.
• text.parse::<i32>() Change text to another type.
• text.to_lowercase() Change text to small letters.
• text.to_uppercase() Change text to big letters.
• text.to_string() Change a value to String type.
• text.lines() Split text into lines, each line one item.
• text.contains("part") Check if text has a part inside, gives (true/false).

Example

let mut text = String::from("Ali");

text.push('!');
text.push_str(" Rust");

let clean = text.trim();

let number = "20".parse::<i32>().unwrap();

let sentence = String::from("I love Rust");
let found = sentence.contains("Rust"); // true or false .
let text = String::from("Ali\nOmar\nSara");

let names = text.lines();

// Input: "Ali\nOmar\nSara"

// Output: Ali, Omar, Sara (each on its own line)

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Clone Description :

value.clone() Make a new copy.

Example

let a = String::from("Ali");
let b = a.clone();

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iter, iter_mut and without iter

iter

// make Borrowing to read items.
for item in vec_name.iter() {
    println!("{:?}", item);
}

without iter

// take Ownership from Vec.
for item in vec_name {
    println!("{:?}", item);
}

iter_mut

// reads item with &mut
for item in vec_name.iter_mut() {
    *item += 1; // change values
}

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Quick Notes

• push() → Add one item.
• push_str() → Add one string.
• pop() → Remove last item.
• remove() → Remove by index.
• len() → Number of items.
• first() → First item.
• last() → Last item.
• iter() → Read all items without taking Ownership.
• trim() → Remove spaces.
• parse() → Change type.
• clone() → Make a new copy.
• text.to_string() → Change a value to String type.
• text.lines() → Split text into lines, each line one item.
• text.to_lowercase() → Change text to small letters.
• text.to_uppercase() → Change text to big letters.
• text.contains("part") → Check if text has a part inside, gives (true/false).