string - Sandeep Pote

Below table see what is String Literal and String Type/Object with differences.

String Literal	String Type
Hard-coded into the executable	Allocated on the heap
Immutable	Mutable
String must be known before compilation i.e. static in nature	Dynamically generated at runtime
Faster	Slower than String literal (reading and writing to the heap is slower)
&str	String::new() or `String::from()`
Small in size since sits in stack	Large in size since sits in heap but not infinite space

String literals are written as follows-

let message: &str = "Welcome to the Rust world!";

String Object/Type is written as follows-

Make the variable mutable and use push_str() method to append the string

let mut content_string = String::from("Welcome");
content_string.push_str( " to the Rust world." );

println!("String object is {}", content_string);

Output

String object is Welcome to the Rust world.

To append the character use push() method.

Converting String literal (&str) to String Type (string)

let  str_literal ="Welcome to Rust";
let str_type = str_literal.to_string();

println!("String literal to type is {}", str_type);

Output-

String literal to type is Welcome to Rust

Converting String Type (string) to String literal (&str)

let str_type = String::from("Welcome to Rust");
let  str_literal = str_type.as_str();

println!("String type to literal is {}", str_literal);

Output

String type to literal is Welcome to Rust

Reference –

Tag: string