How do I include the end value in a range?

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I wanted to create a vector with \'a\'..\'z\' values (inclusive).

This doesn\'t compile:

let vec: Vec = (\'a\'..\'z\'+1).collect();


        
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  • 2020-11-27 08:54

    Inclusive range feature stabilised and released as part of version 1.26. Below is valid syntax for inclusive range

    for i in 1..=3 {
        println!("i: {}", i);
    }
    
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  • 2020-11-27 09:10

    Rust 1.26

    As of Rust 1.26, you can use "inclusive ranges":

    fn main() {
        for i in 0..=26 {
            println!("{}", i);
        }
    }
    

    Rust 1.0 through 1.25

    You need to add one to your end value:

    fn main() {
        for i in 0..(26 + 1) {
            println!("{}", i);
        }
    }
    

    This will not work if you need to include all the values:

    • How to iterate over all byte values (overflowing_literals in `0..256`)

    However, you cannot iterate over a range of characters:

    error[E0277]: the trait bound `char: std::iter::Step` is not satisfied
     --> src/main.rs:2:14
      |
    2 |     for i in 'a'..='z'  {
      |              ^^^^^^^^^ the trait `std::iter::Step` is not implemented for `char`
      |
      = note: required because of the requirements on the impl of `std::iter::Iterator` for `std::ops::RangeInclusive<char>`
    

    See Why can't a range of char be collected? for solutions.

    I would just specify the set of characters you are interested in:

    static ALPHABET: &str = "abcdefghijklmnopqrstuvwxyz";
    
    for c in ALPHABET.chars() {
        println!("{}", c);
    }
    
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