Installation

Using npm:

$ npm i --save calculator-keys

In your frontend project:

import * as keys from 'calculator-keys'

Basic Key Functions

• clear
• decimal
• equals
• negation
• number
• operation
• percent

Clear

Clears the state properties.

keys.clear()

Returns

(object): Returns the state object with empty string properties.

Example

keys.clear()
// => {operand1: '', operand2: '', operator: ''}

Decimal

Converts active operand into a decimal number.

keys.decimal({operand1, operand2, operator})

Arguments

operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Operation to perform.

Returns

(object): Returns a new state object with the converted operand.

Example

keys.decimal({operand1: '1', operand2: '', operator: ''})
// => {operand1: '1.', operand2: '', operator: ''}

keys.decimal({operand1: '1', operand2: '1', operator: 'ADD'})
// => {operand1: '1', operand2: '1.', 'ADD'}

Equals

Performs calculation between operands.

keys.equals({operand1, operand2, operator})

Arguments

operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Operation to perform.

Returns

(object): Returns a new state object with the result of the operation performed.

Example

keys.equals({operand1: '1', operand2: '1', operator: 'ADD'})
// => {operand1: '2', operand2: '', operator: ''}

keys.equals({operand1: '100', operand2: '10', operator: 'DIVIDE'})
// => {operand1: '10', operand2: '', ''}

Negation

Converts the active operand into negative or positive number.

keys.negation({operand1, operand2, operator})

Arguments

operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Operation to perform.

Returns

(object): Returns a new state object with the converted operand.

Example

keys.negation({operand1: '1', operand2: '', operator: ''})
// => {operand1: '-1', operand2: '', operator: ''}

keys.negation({operand1: '1', operand2: '-1', operator: 'ADD'})
// => {operand1: '1', operand2: '1', 'ADD'}

Number

Appends a number to the state object.

keys.number(number, {operand1, operand2, operator})

Arguments

number (string): Number to append. operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Operation to perform.

Returns

(object): Returns a new state object.

Example

keys.number('1', {operand1: '1', operand2: '', operator: ''})
// => {operand1: '11', operand2: '', operator: ''}

keys.number('4', {operand1: '1', operand2: '123', operator: 'ADD'})
// => {operand1: '1', operand2: '1234', 'ADD'}

Operation

Saves the operation in the state object.

keys.operation(newOperation, {operand1, operand2, operator})

Arguments

newOperation (string): New operation to perform. operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Existing operation.

Returns

(object): Returns a new state object.

Example

keys.operation('ADD', {operand1: '1', operand2: '', operator: ''})
// => {operand1: '1', operand2: '', operator: 'ADD'}

keys.operation('MULTIPLY', {operand1: '1', operand2: '1', operator: 'ADD'})
// => {operand1: '2', operand2: '', 'MULTIPLY'}

Percent

Gets the percentage value of the active operand.

keys.percent({operand1, operand2, operator})

Arguments

operand1 (string): First operand property. operand2 (string): Second operand property. operator (string): Operation to perform.

Returns

(object): Returns a new state object with the converted operand.

Example

keys.percent({operand1: '1', operand2: '', operator: ''})
// => {operand1: '0.01', operand2: '', operator: ''}

keys.decimal({operand1: '1', operand2: '1', operator: 'ADD'})
// => {operand1: '1', operand2: '0.01', 'ADD'}