Create a string of variable length, filled with a repeated character

Question

So, my question has been asked by someone else in it\'s Java form here: Java - Create a new String instance with specified length and filled with specific character. Best so

Answer 1

Based on answers from Hogan and Zero Trick Pony. I think this should be both fast and flexible enough to handle well most use cases:

var hash = '####################################################################'

function build_string(length) {  
    if (length == 0) {  
        return ''  
    } else if (hash.length <= length) {  
        return hash.substring(0, length)  
    } else {  
        var result = hash  
        const half_length = length / 2  
        while (result.length <= half_length) {  
            result += result  
        }  
        return result + result.substring(0, length - result.length)  
    }  
}