JSFiddle - React, Tailwind, and code Playground

JavaScript

if ( ! window.never_called_again  ) {
    window.never_called_again = (function () {
        var ran = false;
        return function (args) {
            if ( ran ) return;
            ran = true;
            console.log('Logged only once 1');
        };
    }());
}

never_called_again();

if ( ! window.never_called_again  ) {
    window.never_called_again = (function () {
        var ran = false;
        return function (args) {
            if ( ran ) return;
            ran = true;
            console.log('Logged only once 2');
        };
    }());
}

never_called_again();
never_called_again();
never_called_again();
never_called_again();