Basic Calculator

Description

A basic calculator that just adds, subtract, divides and multiples two input values.

Limitations and/or functionalities

• The calculator can add two input values, the result of the operation can be used as one of the operands.

• The calculator is not programmed to work well with more than two input, thus the result from the following input would be 5 i.e 7 + 2 + 3 = 5

• The calculator does not support:

  • Negative inputs
  • Calculation of percentages
  • Braces
  • Exponentials

Implementation

The calculator makes use of global variables to track the operands, operator and a boolean to track if the result is to be used as the one operand.

The functions implemented in the calculator and what they do are as follow

• clear() resets all the global variables to the initial values and clears the DOM

• enable() enables the equal and dot buttons, the buttons are disenabled when clicked to prevent multiple of it.

• updateDom(value) updates the DOM element with the parameter value.

• equal(sign, firstOp) sets the secondOperand and class the respective operation based on the value of the arg sign.

• handleOperator(sign) sets the global var operator with the arg sign and also the firstOperand

Deployment

A live version of the calculator on github pages.