Import an other JS file in modules directory.

Yes, I'm going to use 7 steppers in my project. It is not only about steppers, OOP is easiest way to build application for me.

By taking advantage @Gordon's code I have build my OOP like this; The way below is easy to read and understand the code for me.

modules/stepperClass.js

exports.stepperClass = function (p1, p2, p3, p4) {
    var step = 0;
    var steps = [0b0001, 0b0011, 0b0010, 0b0110, 0b0100, 0b1100, 0b1000, 0b1001];
    var stepperPins = [p4, p3, p2, p1];

    this.writeStep = function () {
        step++;
        digitalWrite(stepperPins, steps[step % steps.length]);
    };

    this.stop = function () {
        digitalWrite(stepperPins[0], LOW);
        digitalWrite(stepperPins[1], LOW);
        digitalWrite(stepperPins[2], LOW);
        digitalWrite(stepperPins[3], LOW);
    };

    this.doStep = function (cnt) {
        for (i = 0; i < cnt; i++) {
            x = 0;
            while (x < 10) x++;//delay a little bit
            this.writeStep();
        }
        this.stop();
    };

projects/main.js

var stepperClass=require('stepperClass').stepperClass;

stepper1=new stepperClass(A1,A2,A3,A4);
stepper2=new stepperClass(B1,B2,B3,B4);
stepper3=new stepperClass(C1,C2,C3,C4);

stepper1.doStep(100);
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