Javascript sprintf

js

/**
 * Returns a formatted string using the first argument as a printf-like format.
 *
 * The first argument is a string that contains zero or more placeholders.
 * Each placeholder is replaced with the converted value from its corresponding argument.
 *
 * Supported placeholders are:
 *
 * %s - String.
 * %d - Number (both integer and float).
 * %% - single percent sign ('%'). This does not consume an argument.
 *
 * Argument swapping:
 *
 * %1$s ... %n$s
 *
 * When using argument swapping, the n$ position specifier must come immediately
 * after the percent sign (%), before any other specifiers, as shown in the example below.
 *
 * If the placeholder does not have a corresponding argument, the placeholder is not replaced.
 *
 * @author odan
 *
 * @param {...*} format [, args [, ...*]
 * @returns {String}
 */
 sprintf() {
        if (arguments.length < 2) {
            return arguments[0];
        }
        let index = 1;
        const result = (args[0] + "").replace(/%((\d)\$)?([sd%])/g, function (match, _group_, pos, _format_) {
            if (match === "%%") {
                return "%";
            }
            if (typeof pos === "undefined") {
                pos = index++;
            }
            if (pos in args && pos > 0) {
                return args[pos];
            } else {
                return match;
            }
        });
        return result;
    }