Function array_utils::initialize_till

pub fn initialize_till<T, F, const OUTPUT_SIZE: usize>(
    f: F, 
    till: T, 
    fill: T
) -> ([T; OUTPUT_SIZE], usize) where
    T: Copy + PartialEq,
    F: Fn(usize) -> T, 

Initialize a sized array from a closure till a certain value appears.

Generates a new sized array generated from generator closure, which turns a index into a element of the generated array. If the given till value is found, the rest of the output array is filled with the fill value. Along with the generated array, this utility returns at what index the given till value was found (OUTPUT_SIZE if not found).

Examples

use array_utils::initialize_till;

let till_five: ([usize; 8], usize) = initialize_till(
    |index| index,  // Generator closure
    5,              // Till this value
    42              // Fill the rest with
);
assert_eq!(till_five, ([0, 1, 2, 3, 4, 42, 42, 42], 5));

// Especially useful for null terminated data streams.
fn get_stream_byte() -> u8 {
    // ...snip
}

// Fetch stream bytes till it find a `0` byte. Fill the rest with `0` bytes.
assert_eq!(initialize_till(|_| get_stream_byte(), 0, 0), ([4, 2, 1, 3, 3, 7, 0, 0, 0], 6));

Panics

Only panics if the given f panics.