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//- Design credit goes to Jaroslav Getman
//- https://dribbble.com/shots/2334270-004-Calculator
template(data-template="calculatorbutton")
.Calculator-button(v-bind:class="className")
//- NOTE: Changing it to {{ button.text }} breaks in IE
//- HACK: using @click.stop because event fires twice sometimes
span(
v-bind:class="['btest', button.icon ? button.icon : '']"
v-if="button.children == null"
v-text="button.text"
@click.stop="emitAction($event, button)"
)
span(
v-for="childButton in button.children"
v-bind:class="[childButton.className || ' btest ', 'btest']"
v-text="childButton.text"
@click.stop="emitAction($event, childButton)"
)
div.App.js-app(v-bind:style="{ opacity: appLoaded ? 1 : 0 }")
div.Calculator
header.Calculator-header
div.Calculator-expressions
span.Calculator-expressionsOverflow
span.Calculator-expressionsList {{ expressionList }}
div.Calculator-operands
span.Calculator-currentOperand(
v-bind:class="{ 'has-error': error }"
v-bind:style="{ 'font-size': font.size, 'font-weight': font.weight }"
) {{ operand }}
div.Calculator-body
div.Calculator-buttonsContainer
div(
v-for="button in buttons"
is="calculatorbutton"
v-bind:button="button"
) {{ button.children }}
div.Calculator-equals(@click.stop="$store.dispatch('showTotal', { explicit: true })")
div.Calculator-equalsLine
div.Calculator-equalsLine
//
// -> Design credit goes to Jaroslav Getman
// -> https://dribbble.com/shots/2334270-004-Calculator
//
@import url('https://cdnjs.cloudflare.com/ajax/libs/ionicons/2.0.1/css/ionicons.min.css')
@import url('https://fonts.googleapis.com/css?family=Source+Sans+Pro:400,300,400italic,600,700,900,200')
@import 'bourbon'
$foreground--dark: #151515
$background-gradient-1: #B6B2AB
$background-gradient-2: #B3AFA7
$background-gradient-3: #B8B5AF
$background-gradient-4: #78736B
$background-gradient-5: #6F6862
$background-gradient-6: #58504B
$background-gradient-7: #5F574E
$background-gradient-8: #625A51
// I don't know how to get the colors closer here, would need the actual hsla
$gradient-blue-1: hsla(226, 12%, 40%, 0.76)
$gradient-blue-2: hsla(222, 12%, 13%, 0.80)
$gradient-orange-1: #FF8D4B
$gradient-orange-2: #FF542E
$calculator-width: 260px
$header-padding-left: 20px
@function negative($value)
@return -(abs($value))
@mixin calcbutton
&
cursor: pointer
transition: box-shadow 0.2s, background-color 0.15s
text-shadow: 1px 1px 2px rgba(black, 0.15)
&:hover
background: rgba(black, 0.08)
&:active,
&.is-active
box-shadow: inset 0 3px 15px 0 rgba(black, 0.3)
&.has-children:hover,
&.has-children:active
background: initial
box-shadow: none
cursor: default
html
box-sizing: border-box
color: #222
font-size: 1rem
font-family: Source Sans Pro
line-height: 1.5
text-rendering: optimizeLegibility
*,
*:before,
*:after
box-sizing: inherit
body
background:
size: cover
repeat: no-repeat
+linear-gradient(135deg, $background-gradient-1 0%, $background-gradient-2 25%, $background-gradient-3 25%, $background-gradient-4 50%, $background-gradient-5 50%, $background-gradient-6 75%, $background-gradient-7 75%, $background-gradient-8 100%)
min-height: 100vh
.App
opacity: 0
transition: opacity 0.3s
.Calculator
box-shadow: 12px 18px 45px 0 rgba(black, 0.25)
cursor: default
margin: 0 auto
transform: translate(-50%, -50%)
user-select: none
+position(absolute, 50% null null 50%)
+size($calculator-width null)
.Calculator-header
background: white
overflow: hidden
padding: 20px $header-padding-left
position: relative
text-align: right
@at-root
$height: 22px
.Calculator-expressions
color: adjust-color($gradient-blue-1, $saturation: -20, $lightness: 22)
display: block
float: right
font-size: 15px
line-height: $height
min-height: $height
position: relative
white-space: nowrap
width: 100%
word-wrap: normal
.Calculator-expressionsList
display: block
float: right
// Not sure how to represent that there are more expressions to the left
.Calculator__expressionsOverflow
$width: 2px
color: #333
box-shadow: 5px 0 20px 4px rgba(black, 0.3)
font-weight: 700
opacity: 0
padding-right: 0px
text-align: center
transition: opacity 0.5s
transform: translate(0, -50%)
+position(absolute, 50% null null negative($header-padding-left) - $width - 2)
+size($width $height - 5)
&:before
content: ''
&.is-showing
opacity: 1
.Calculator-operands
color: $foreground--dark
font-size: 60px
font-weight: 200
line-height: 1.1
clear: both
.Calculator-currentOperand
display: block
overflow: visible
min-height: 60px
line-height: 60px
float: right
transition-duration: 0.2s
transition-property: font-size
&.has-error
color: hsla(10,85%,57%,1)
.Calculator-body
background: white
.Calculator-buttonsContainer
$overflow: 18px
display: flex
flex-wrap: wrap
overflow: visible
position: relative
&:before
+linear-gradient(top, darken($gradient-blue-1, 0), darken($gradient-blue-2, 0))
box-shadow: 17px 27px 72px 1px rgba(black, 0.3)
filter: drop-shadow(0px 0px 7px rgba(black, 0.2))
content: ''
+position(absolute, 0 negative($overflow) 0 negative($overflow))
.Calculator-button
color: rgba(white, 0.8)
cursor: pointer
font-size: 24px
font-weight: 300
flex: 25%
line-height: 70px
text-align: center
position: relative
z-index: 1
+calcbutton
> span
display: block
.Calculator-button--negation,
.Calculator-button--modulo
font-size: 18px
.Calculator-button--square
font-size: 16px
.Calculator-button--division
font-size: 20px
.Calculator-button--multiplication
font-size: 30px
.Calculator-button--addition
font-size: 26px
.Calculator-button--subtraction
font-size: 25px
.Calculator-button--paren
display: flex
font-size: 18px
&:hover,
&:active
background: initial !important
box-shadow: none !important
cursor: default !important
> span
flex: 50%
+calcbutton
.Calculator-equals
+linear-gradient(left, $gradient-orange-1, $gradient-orange-2)
cursor: pointer
padding: 26px 0
position: relative
z-index: -1
.Calculator-equalsLine
background: white
display: block
margin: 0 auto 6px
box-shadow: 0px 0px 2px rgba(black, 0.4)
+size(20px 1px)
.Calculator-equalsLine:last-child
margin-bottom: 0
/*
-> Design credit goes to Jaroslav Getman
-> https://dribbble.com/shots/2334270-004-Calculator
Calculator 2.0
This is the second iteration of this calculator, built with Vue and Vuex. You can find the code for this new version of the calculator and the old calculator here.
github.com/anthonykoch/calculator
TODO:
1. Make buttons show keypress when a keybind is pressed
FIXME:
1. Fix error where Expressions = ['(', '5', '*', '3', ')'] and mode is APPEND after ")". It should be insert
2. Even though pressing delete causes mutation CLEAR_ENTRY to fire, changing the state does nothing until a button has been pressed. Not sure if this is a problem with Vuex or the way I'm doing it.
*/
function main() {
'use strict';
const $ = document.querySelector.bind(document);
const $app = $('.js-app');
const templates = {
calculatorButton: $(`[data-template="calculatorbutton"]`).innerHTML
};
const ACTION_CLEAR = 'clear';
const ACTION_CLEAR_ENTRY = 'clearEntry';
const ACTION_NEGATE = 'negate';
const ACTION_UPDATE_OPERATOR = 'updateOperator';
const ACTION_APPEND_OPERAND = 'appendOperand';
const ACTION_ADD_PAREN = 'addParen';
const ACTION_BACKSPACE = 'backspace';
const ACTION_SHOW_TOTAL = 'showTotal';
const buttons = [
{
text: 'C',
className: 'clear',
action: ACTION_CLEAR
},
{
text: '+/-',
className: 'negation',
action: ACTION_NEGATE
},
{
text: '%',
className: 'modulo',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: '%',
}
},
{
text: '√',
className: 'square',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: 'yroot',
}
},
{
text: '7',
action: ACTION_APPEND_OPERAND,
payload: {
value: '7',
}
},
{
text: '8',
action: ACTION_APPEND_OPERAND,
payload: {
value: '8',
}
},
{
text: '9',
action: ACTION_APPEND_OPERAND,
payload: {
value: '9',
}
},
{
text: '/',
className: 'division',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: '/',
}
},
{
text: '4',
action: ACTION_APPEND_OPERAND,
payload: {
value: '4',
}
},
{
text: '5',
action: ACTION_APPEND_OPERAND,
payload: {
value: '5',
}
},
{
text: '6',
action: ACTION_APPEND_OPERAND,
payload: {
value: '6',
}
},
{
text: '',
className: 'multiplication',
icon: 'ion-ios-close-empty',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: '*',
}
},
{
text: '1',
action: ACTION_APPEND_OPERAND,
payload: {
value: '1',
}
},
{
text: '2',
action: ACTION_APPEND_OPERAND,
payload: {
value: '2',
}
},
{
text: '3',
action: ACTION_APPEND_OPERAND,
payload: {
value: '3',
}
},
{
text: '',
className: 'subtraction',
icon: 'ion-ios-minus-empty',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: '-',
}
},
{
text: '0',
action: ACTION_APPEND_OPERAND,
payload: {
value: '0',
}
},
{
className: 'paren',
children: [
{
text: '(', className: 'open-paren',
action: ACTION_ADD_PAREN,
payload: {
operator: '(',
}
},
{
text: ')', className: 'close-paren',
action: ACTION_ADD_PAREN,
payload: {
operator: ')',
}
}
]
},
{
text: '.',
action: ACTION_APPEND_OPERAND,
payload: {
value: '.',
}
},
{
text: '',
className: 'addition',
icon: 'ion-ios-plus-empty',
action: ACTION_UPDATE_OPERATOR,
payload: {
operator: '+',
}
}
];
// Mode show total causes the total to be displayed in the current operand display
const MODE_SHOW_TOTAL = 1 << 1;
// Mode insert operand causes the current operand to be overwritten. After the first character has been written, the mode should go to mode append operand
const MODE_INSERT_OPERAND = 1 << 2;
// Mode append operand causes any operand parts to be appended to the current operand
const MODE_APPEND_OPERAND = 1 << 3;
// The maximum number of digits the current operand may be
const MAX_NUMBER_LENGTH = Number.MAX_SAFE_INTEGER.toString().length;
const initialState = {
activeButtons: [],
buttons,
expressions: ['5', '+', '7', '-', '45', '+', '3', '+', '177', '-'],
currentOperand: '147',
currentOperator: '-',
mode: MODE_SHOW_TOTAL|MODE_INSERT_OPERAND,
openParenStack: 0,
error: null,
total: 147,
};
const mutations = {
CLEAR(state) {
state.expressions = [];
state.currentOperand = '0';
state.currentOperator = '';
state.openParenStack = 0;
state.mode = MODE_SHOW_TOTAL|MODE_INSERT_OPERAND;
state.error = null;
state.total = 0;
},
BACKSPACE(state) {
let operand = state.currentOperand.slice(0, -1);
if (operand.length === 0) {
operand = '0';
}
state.currentOperand = operand;
},
CLEAR_ENTRY(state) {
state.currentOperand = '0';
},
NEGATE(state) {
// Only add negative sign if not zero
if (state.currentOperand !== 0) {
state.currentOperand = (-state.currentOperand).toString();
}
},
UPDATE_OPERATOR(state, { operator }) {
const length = state.expressions.length;
const last = state.expressions[length - 1] || '';
const { mode, currentOperand } = state;
if (mode & MODE_INSERT_OPERAND) {
console.log('MODE_INSERT_OPERAND');
if (length === 0) {
state.expressions.push(currentOperand, operator);
} else if (isOperator(last)) {
// console.log('isoplast'); // APPEND_OP LOG
state.expressions.pop();
state.expressions.push(operator);
} else if (last === ')') {
// console.log('nope'); // APPEND_OP LOG
state.expressions.push(operator);
} else if (last === '(') {
state.expressions.push(currentOperand, operator);
} else {
// console.log('else'); // APPEND_OP LOG
}
} else if (mode & MODE_APPEND_OPERAND) {
console.log('MODE_APPEND_OPERAND');
if (length === 0) {
console.log('length 0'); // APPEND_OP LOG
state.expressions.push(currentOperand, operator);
} else if (isOperator(last)) {
// console.log('isOperator(last)'); // APPEND_OP LOG
state.expressions.push(currentOperand, operator);
} else if (last === ')') {
// console.log('last === )'); // APPEND_OP LOG
state.expressions.push(operator);
} else if (last === '(') {
// console.log('last === ('); // APPEND_OP LOG
state.expressions.push(currentOperand, operator);
} else {
// console.log('else');
// state.expressions.push(operator, currentOperand);
}
}
state.currentOperator = operator;
state.mode = MODE_INSERT_OPERAND|MODE_SHOW_TOTAL;
console.log('UPDATE_OPERATOR:', state.expressions);
},
ADD_PAREN(state, { operator }) {
const last = state.expressions[state.expressions.length - 1] || '';
const { currentOperand, openParenStack } = state;
// console.log('ADD_PAREN:', {last, operator});
if (operator === ')' && openParenStack === 0) {
// No need to add closing paren if there is no open paren
return;
} else if (operator === '(' && last === ')') {
// FIXME: Look at real calculator for semantics
return;
}
if (last === '(' && operator === ')') {
// Handle immediate closed parens
state.expressions.push(currentOperand, operator);
} else if (isOperator(last) && operator === ')') {
// Automatically append current operand when expressions
// is "(5 *" so result is "(5 * 5)"
state.expressions.push(currentOperand, operator);
} else if ((isOperator(last) || length === 0) && operator === '(') {
// Handle "5 *" where the result is "5 * (" and "(" is the beginning
// of a new group expression
state.expressions.push(operator);
}
if (operator === '(') {
state.openParenStack++;
} else if (operator === ')') {
state.openParenStack--;
}
console.log('ADD_PAREN');
},
APPEND_OPERAND(state, { value, operator }) {
const currentOperand = state.currentOperand;
let newOperand = currentOperand;
let newMode;
// Don't append 0 to 0
if (value === '0' && currentOperand[0] === '0') {
return;
} else if (value === '.' && currentOperand.includes('.')) {
// Avoid appending multiple decimals
return;
}
// Switch modes from showing the total to the current operand
if (state.mode & MODE_SHOW_TOTAL) {
newMode = MODE_INSERT_OPERAND;
}
if (state.mode & MODE_INSERT_OPERAND) {
// console.log('INSERT');
newOperand = value.toString();
state.mode = MODE_APPEND_OPERAND;
} else {
// console.log('APPEND');
newOperand += value.toString();
}
// TODO: Update font size, actually should do that in the vm
state.currentOperand = newOperand.substring(0, MAX_NUMBER_LENGTH);
},
SHOW_TOTAL(state, { $commit, explicit }={}) {
const last = state.expressions[state.expressions.length - 1] || '';
const expressions = state.expressions.slice(0);
const currentOperand = state.currentOperand;
const mode = state.mode;
const currentTotal = state.total;
const openParenStack = state.openParenStack;
const isFirstNumber = typeof Number(expressions[0]) === 'number';
const isSecondOperator = isOperator(expressions[1] || '');
const length = expressions.length;
let times = openParenStack;
let total;
if (expressions.length === 0) {
return;
}
else if (explicit && isFirstNumber && isSecondOperator && length === 2) {
// Handle case where expressions is 5 *
// console.log('explicit && isFirstNumber && isSecondOperator');
expressions.push(currentOperand);
}
else if (explicit && isOperator(last)) {
// Handle case where expressions is ['5', '*', '4', '+'] and
// the total is being explicitly being requested
// console.log('explicit && isOperator(last)', isOperator(last), last);
if (mode & MODE_INSERT_OPERAND) {
expressions.push(currentTotal);
} else if (mode & MODE_APPEND_OPERAND) {
expressions.push(currentOperand);
}
}
else if (isOperator(last)) {
// Handle case where expressions is ['5', '*', '4', '+']
// console.log('isOperator(last)');
expressions.pop();
}
if (explicit) {
// Automatically close parens when explicitly requesting
// the total
let times = openParenStack;
while (times-- > 0) {
expressions.push(')');
}
} else if ( ! explicit && openParenStack === 1) {
// Auto close if there is only one missing paren
expressions.push(')');
}
try {
total = MathParser.eval(expressions.join(' '));
if (explicit) {
$commit('CLEAR');
}
state.total = total;
} catch (err) {
if (explicit) {
$commit('CLEAR');
state.error = err;
console.log(err);
}
}
console.log(
'SHOW_TOTAL; Expressions: "%s"; Total: %s; Explicit: %s',
expressions.join(' '),
total,
!! explicit);
}
};
const actions = {
clear({ commit }) {
commit('CLEAR');
console.log('');
},
backspace({ commit }) {
commit('BACKSPACE');
console.log('');
},
clearEntry({ commit }) {
commit('CLEAR_ENTRY');
console.log('');
},
negate({ commit }) {
commit('NEGATE');
console.log('');
},
updateOperator({ commit }, payload) {
commit('UPDATE_OPERATOR', payload);
commit('SHOW_TOTAL', {
...payload,
$commit: commit,
});
console.log('');
},
appendOperand({ commit }, payload) {
commit('APPEND_OPERAND', payload);
commit('SHOW_TOTAL', {
...payload,
$commit: commit,
});
console.log('');
},
showTotal({ commit }, payload) {
// FIXME: Probably not supposed to pass commit, but idk
// how else to do it
commit('SHOW_TOTAL', {
...payload,
$commit: commit,
});
console.log('');
},
addParen({ commit }, payload) {
commit('ADD_PAREN', payload);
commit('SHOW_TOTAL', {
...payload,
$commit: commit,
});
console.log('');
}
};
const store = window.store = new Vuex.Store({
state: initialState,
actions,
mutations,
});
Vue.component('calculatorbutton', {
props: ['button'],
template: templates.calculatorButton,
computed: {
className() {
const button = this.button;
let className = '';
if (button.children) {
className += ' has-children ';
}
if (button.className) {
className += ` Calculator-button--${button.className} `;
}
return className;
}
},
methods: {
emitAction($event, button) {
this.$store.dispatch(button.action, button.payload);
}
}
});
// [...document.querySelectorAll('.btest')].forEach(item => {
// item.addEventListener('click', () => {
// console.log('btest');
// });
// })
const app = new Vue({
el: $app,
store,
mounted() {
setTimeout(() => this.appLoaded = true, 100)
},
data: {
console,
appLoaded: false,
},
computed: {
...Vuex.mapState([
'buttons',
'expressions',
'currentOperand',
'currentOperator',
'openParenStack',
'total',
'error',
'mode'
]),
operand() {
let operand;
if (this.error) {
return 'Error';
}
console.log('Flags:', getFlags(this.mode));
if (this.mode & MODE_SHOW_TOTAL) {
operand = this.total.toString();
console.log('DISPLAY_TOTAL', this.total.toString());
} else {
operand = this.currentOperand;
console.log('DISPLAY_CURRENT', this.currentOperand);
}
return operand;
},
expressionList() {
return this.expressions.map((str, index, array) => {
const s = str.trim();
if (array[index -1] === '(') {
return s;
} else if (s === ')') {
return s
} else if (s[0] === '-' && isNumberPart(s[1])) {
return ' ' + str;
} else {
return ' ' + s;
}
return str;
})
.join('');
},
font() {
let length;
if (this.mode & MODE_SHOW_TOTAL) {
length = this.total.toString().length;
} else {
length = this.currentOperand.toString().length;
}
let size;
let weight;
if (length < 8) {
size = '60px';
weight = '200';
} else if (length <= MAX_NUMBER_LENGTH) {
size = '28px';
weight = '300';
} else if (length >= MAX_NUMBER_LENGTH) {
size = '24px';
weight = '300';
}
return { size, weight };
},
}
});
const Key = {
Backspace: 8,
Delete: 46,
Enter: 13,
Escape: 27,
Multiply: 106,
Add: 107,
Subtract: 109,
Decimal: 110,
Divide: 111,
Equals: 187,
Dash: 189,
ForwardSlash: 191,
0: 48,
1: 49,
2: 50,
3: 51,
4: 52,
5: 53,
6: 54,
7: 55,
8: 56,
9: 57,
Numpad0: 96,
Numpad1: 97,
Numpad2: 98,
Numpad3: 99,
Numpad4: 100,
Numpad5: 101,
Numpad6: 102,
Numpad7: 103,
Numpad8: 104,
Numpad9: 105,
};
const KeyTranslate = {
48: '0',
49: '1',
50: '2',
51: '3',
52: '4',
53: '5',
54: '6',
55: '7',
56: '8',
57: '9',
96: '0',
97: '1',
98: '2',
99: '3',
100: '4',
101: '5',
102: '6',
103: '7',
104: '8',
105: '9',
106: '*',
107: '+',
109: '-',
111: '/',
189: '-',
191: '/',
};
const OperatorKeys = [Key.Multiply, Key.Add, Key.Subtract, Key.Divide];
window.addEventListener('keydown', function onWindowKeydown(e) {
const { keyCode: key,
ctrlKey,
shiftKey } = e;
// console.log(key, e.key, e.which);
if (shiftKey && key === Key['9']) {
store.dispatch(ACTION_ADD_PAREN, {
operator: '('
});
}
else if (shiftKey && key === Key['0']) {
store.dispatch(ACTION_ADD_PAREN, {
operator: ')'
});
}
else if (shiftKey && key === Key['8']) {
store.dispatch(ACTION_UPDATE_OPERATOR, {
operator: '*'
});
}
else if (shiftKey && key === Key.Equals) {
store.dispatch(ACTION_UPDATE_OPERATOR, {
operator: '+'
});
}
else if (key === Key.Dash) {
store.dispatch(ACTION_UPDATE_OPERATOR, {
operator: '-'
});
}
else if ((key >= 48 && key <= 57) || (key >= 96 && key <= 105)) {
store.dispatch(ACTION_APPEND_OPERAND, {
value: KeyTranslate[key]
});
}
else if (key === Key.Decimal) {
store.dispatch(ACTION_APPEND_OPERAND, {
value: '.'
});
}
else if ([Key.Multiply, Key.Add, Key.Subtract, Key.Divide].includes(key)) {
store.dispatch(ACTION_UPDATE_OPERATOR, {
operator: KeyTranslate[key]
});
}
else if (key === Key.Backspace) {
store.dispatch(ACTION_BACKSPACE);
return e.preventDefault();
}
else if (key === Key.Delete) {
store.dispatch(ACTION_CLEAR_ENTRY);
return e.preventDefault();
}
else if (key === Key.Enter) {
store.dispatch(ACTION_SHOW_TOTAL, {
explicit: true
});
return e.preventDefault();
}
else if (key === Key.Escape) {
store.dispatch(ACTION_CLEAR);
return e.preventDefault();
}
});
// Debug function for flags
function getFlags(flags) {
let arr = [];
if (flags & MODE_SHOW_TOTAL) {
arr.push('MODE_SHOW_TOTAL');
}
if (flags & MODE_INSERT_OPERAND) {
arr.push('MODE_INSERT_OPERAND');
}
if (flags & MODE_APPEND_OPERAND) {
arr.push('MODE_APPEND_OPERAND');
}
return arr.join('|');
}
};
// TODO NEXT:
function getTotal(cb) {
try {
const total = MathParser.eval(this.expressions.join(''));
return cb(null, total);
} catch (err) {
cb(err);
console.log(err);
}
}
function isNumberPart(str) {
return (/^[0-9.]/).test(str);
}
setTimeout(main, 100);
// Have to mock commonjs because this was developed in node
const { MathParser, isOperator, operators } = (function (module) {
var exports = module.exports;
'use strict';
const Token = exports.Token = {
NumericLiteral: 'NumericLiteral',
Punctuator: 'Punctuator'
};
/**
* Regex for numeric decimal literal constructed from ECMAScript spec
*/
const RE_NUMERIC_LITERAL = exports.RE_NUMERIC_LITERAL =
/^(?:(?:0x[0-9a-fA-F]+|0X[0-9a-fA-F]+)|(?:0[oO][0-7]+)|(?:0[bB][01]+)|(?:(?:0|[1-9](?:[0-9]+)?)\.(?:[0-9]+)?|\.[0-9]+|(?:0|[1-9](?:[0-9]+)?))(?:[eE](?:[-+][0-9]+))?)/;
const operators =
exports.operators = ['/', '*', '**', '-', '+', 'yroot', '%'];
const punctuation =
exports.punctuation = ['(', ')', ...operators];
// All the operators, sorted by longest string length
const RE_PUNCTUATION = exports.RE_PUNCTUATION =
new RegExp(
'^(?:'
+ punctuation.slice(0)
.sort((a, b) => b.length - a.length)
.map(str => escapeRegExp(str))
.join('|')
+ ')'
);
const isOperator =
exports.isOperator = (str) => operators.includes(str);
/**
* Courtesy of
* http://stackoverflow.com/questions/3446170/escape-string-for-use-in-javascript-regex
*/
function escapeRegExp(str) {
return str.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
}
function isWhitespace(str) {
return /^\s$/.test(str);
}
/**
* A Lexer
* @param {String} data
* @param {Object} options
*/
const Lexer = exports.Lexer = class Lexer {
constructor(data, options) {
let source = data;
if (source.charAt(0) === '\uFEFF') {
source = source.slice(1);
}
source = source.replace(/\r\n|[\n\r]/g, '\n');
this.source = source;
this.input = source;
this.position = 0;
this.stash = [];
this.column = 0;
this.line = 1;
}
static all(data, options) {
const lexer = new Lexer(data, options);
const tokens = [];
let token;
while (token = lexer.nextToken()) {
tokens.push(token);
}
return tokens;
}
lex() {
const token =
null
|| this.getPunctuationToken()
|| this.getNumericToken()
if (token == null) {
this.error(`Unexpected token at (${this.position})`);
// this.error(`Unexpected token (${this.line}:${this.column})`);
}
return token;
}
forward(index) {
this.position += index;
this.input = this.input.substring(index, this.source.length);
}
getPunctuationToken() {
const position = this.position;
const match = this.input.match(RE_PUNCTUATION);
if (match) {
this.forward(match[0].length);
return {
type: Token.Punctuator,
value: match[0],
start: position,
end: this.position
};
}
return null;
}
getNumericToken() {
const position = this.position;
const match = this.input.match(RE_NUMERIC_LITERAL);
if (match) {
this.forward(match[0].length);
return {
type: Token.NumericLiteral,
raw: match[0],
value: Number(match[0]),
start: position,
end: this.position
};
}
return null;
}
hasEnded() {
return this.input.length === 0;
}
skipWhitespace() {
let position = this.position;
let times = 0;
let char;
while (position < this.source.length) {
char = this.input[times];
if (isWhitespace(char)) {
position++;
times++;
if (char === '\n') {
this.line++;
this.column = 0;
}
} else {
break;
}
}
this.position = position;
this.input = this.input.substring(times, this.source.length);
}
/**
* Returns the next token without consuming the token or null if no
* tokens can be found.
*
* @return {Object|null}
*/
peek() {
return this.lookahead(1);
}
/**
* Returns the token at `index` or `null` if there are no more tokens.
*
* @param {Number} index - The number of tokens to look ahead
* @return {Object|null}
*/
lookahead(index) {
const { stash } = this;
let times = index - stash.length;
let token;
if (index < 0) {
this.error('Lookahead index can not be less than 0');
}
if (stash[index - 1] !== undefined) {
return stash[index - 1];
}
while (times-- > 0) {
this.skipWhitespace();
if (this.hasEnded()) {
break;
}
token = this.lex();
if (token) {
stash.push(token);
}
}
return stash[index - 1] || null;
}
nextToken() {
if (this.stash.length) {
return this.stash.shift();
} else if (this.hasEnded()) {
return null;
}
this.skipWhitespace();
if (this.hasEnded()) {
return null;
}
return this.lex();
}
error(message) {
const err = new Error(message);
throw err;
}
};
const Parser = exports.Parser = class Parser {
constructor(data, options) {
this.lexer = new Lexer(data, options);
}
peek() {
return this.lexer.peek();
}
next() {
return this.lexer.nextToken();
}
error(message) {
const err = new Error(message);
throw err;
}
parsePrimary() {
let token = this.peek();
let expression;
if (token == null) {
this.error('Unexpected end of input');
}
if (token.value === '(') {
token = this.next();
expression = this.parseExpression();
token = this.next();
if (token == null) {
this.error(`Unexpected end of input`);
} else if (token.value !== ')') {
this.error(`Unexpected token ${token.value}`);
}
return expression;
} else if (token.type === Token.NumericLiteral) {
token = this.next();
return new Literal(token.raw, token.value);
}
this.error(`Unexpected token "${token.value}"`);
}
parseUnary() {
let token = this.peek();
if (token && (token.value === '-' || token.value === '+')) {
token = this.next();
return new UnaryExpression(token.value, this.parseUnary());
}
return this.parsePrimary();
}
// I'm not sure what these pow and nth square root operators are classified as
parsePowAndSquare() {
let expression = this.parseUnary();
let token = this.peek();
if (token == null) {
return expression;
}
while (token && (token.value === '**' || token.value == 'yroot')) {
token = this.next();
const operator = token.value;
const left = expression;
const right = this.parseUnary();
expression = new BinaryExpression(operator, left, right);
token = this.peek();
}
return expression;
}
parseMultiplicative() {
let expression = this.parsePowAndSquare();
let token = this.peek();
if (token == null) {
return expression;
}
while (token && (token.value === '*' || token.value == '/' || token.value === '%')) {
token = this.next();
const operator = token.value;
const left = expression;
const right = this.parsePowAndSquare();
expression = new BinaryExpression(operator, left, right);
token = this.peek();
}
return expression;
}
parseAdditive() {
let expression = this.parseMultiplicative();
let token = this.peek();
while (token && (token.value === '+' || token.value === '-')) {
token = this.next();
const operator = token.value;
const left = expression;
const right = this.parseMultiplicative();
expression = new BinaryExpression(operator, left, right, token.start, token.end);
token = this.peek();
}
return expression;
}
parseExpression() {
return this.parseAdditive();
}
parse() {
return this.parseExpression();
}
}
class UnaryExpression {
constructor(operator, expression) {
this.type = 'UnaryExpression';
this.operator = operator;
this.expression = expression;
}
}
class BinaryExpression {
constructor(op, left, right, start, end) {
this.type = 'BinaryExpression';
this.operator = op;
this.left = left;
this.right = right;
this.start = start;
this.end = end;
}
}
class Literal {
constructor(raw, value) {
this.type = 'Literal';
this.raw = raw;
this.value = value;
}
}
const operations = {
'+': (a, b) => a + b,
'-': (a, b) => a - b,
'*': (a, b) => a * b,
'/': (a, b) => a / b,
'%': (a, b) => a % b,
'**': (a, b) => Math.pow(a, b),
// NOTE: Apparently this is a naive implementation of nth root
// http://stackoverflow.com/questions/7308627/javascript-calculate-the-nth-root-of-a-number
'yroot': (a, b) => Math.pow(a, 1 / b),
};
/**
* Evaluates the AST produced from the parser and returns its result
* @return {Number}
*/
const evaluateAST = exports.evaluateAST = (node) => {
let a;
switch (node.type) {
case 'Expression':
return evaluateAST(node.expression);
case 'Literal':
return parseFloat(node.value);
case 'UnaryExpression':
a = evaluateAST(node.expression);
switch (node.operator) {
case '+':
return +a;
case '-':
return -a;
default:
throw new Error(`Parsing error: Unrecognized unary operator "${node.operator}"`);
}
case 'BinaryExpression':
const { left, right, operator } = node;
const operation = operations[operator];
if (operation === undefined) {
throw new Error('Unsupported operand');
}
return operation(evaluateAST(left), evaluateAST(right));
default:
throw new Error(`Parsing error: Unrecognized node type "${node.type}"`);
}
};
/**
* Evaluates the expression passed and returns its result.
*
* @param {String} expression - The expression to evaluate
* @return {Number}
*/
const MathParser = exports.MathParser = {
eval(expression) {
const ast = new Parser(expression).parse();
return evaluateAST(ast);
}
}
if (typeof window === 'object' && window) {
window.MathParser = MathParser;
window.e = function () {
return MathParser.eval(...arguments);
};
window.parse = function () {
return Parser.parse(...arguments);
};
window.lex = function () {
return Lexer.all(...arguments);
};
}
return module.exports;
}({ exports: {} }));
Also see: Tab Triggers