Check if a string is empty or blank

What's the proper way to check if a string is empty or blank for a) &str b) String? I used to do it by "aaa".len() == 0, but there should another way as my gut tells me?

Both &str and String have a method called is_empty:

• Documentation for &str::is_empty

• Documentation for String::is_empty

This is how they are used:

assert_eq!("".is_empty(), true); // a)
assert_eq!(String::new().is_empty(), true); // b)

Stack Overflow Q#26605224, score: 91