2019-11-05 02:09:40 -01:00
|
|
|
---
|
|
|
|
|
id: 5d792536970cd8e819cc8a96
|
2020-08-25 02:19:45 -07:00
|
|
|
title: Part 78
|
2019-11-05 02:09:40 -01:00
|
|
|
challengeType: 0
|
|
|
|
|
---
|
|
|
|
|
|
|
|
|
|
## Description
|
|
|
|
|
<section id='description'>
|
|
|
|
|
|
|
|
|
|
You can define arrow functions without arguments:
|
|
|
|
|
|
|
|
|
|
```js
|
|
|
|
|
const two = () => 2;
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
Define an empty arrow function without arguments and assign it to `window.onload`.
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Instructions
|
|
|
|
|
<section id='instructions'>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Tests
|
|
|
|
|
<section id='tests'>
|
|
|
|
|
|
|
|
|
|
```yml
|
|
|
|
|
tests:
|
|
|
|
|
- text: See description above for instructions.
|
|
|
|
|
testString: assert(code.replace(/\s/g, "").includes("window.onload=()=>"));
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Challenge Seed
|
|
|
|
|
<section id='challengeSeed'>
|
|
|
|
|
|
|
|
|
|
<div id='html-seed'>
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<script>
|
|
|
|
|
|
|
|
|
|
const infixToFunction = {
|
|
|
|
|
"+": (x, y) => x + y,
|
|
|
|
|
"-": (x, y) => x - y,
|
|
|
|
|
"*": (x, y) => x * y,
|
|
|
|
|
"/": (x, y) => x / y
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const infixEval = (str, regex) =>
|
|
|
|
|
str.replace(regex, (_, arg1, fn, arg2) =>
|
|
|
|
|
infixToFunction[fn](parseFloat(arg1), parseFloat(arg2))
|
|
|
|
|
);
|
|
|
|
|
|
|
|
|
|
const highPrecedence = str => {
|
|
|
|
|
const regex = /([0-9.]+)([*\/])([0-9.]+)/;
|
|
|
|
|
const str2 = infixEval(str, regex);
|
|
|
|
|
return str === str2 ? str : highPrecedence(str2);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const spreadsheetFunctions = {
|
|
|
|
|
"": x => x
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const applyFn = str => {
|
|
|
|
|
const noHigh = highPrecedence(str);
|
|
|
|
|
const infix = /([0-9.]+)([+-])([0-9.]+)/;
|
|
|
|
|
const str2 = infixEval(noHigh, infix);
|
|
|
|
|
const regex = /([a-z]*)\(([0-9., ]*)\)(?!.*\()/i;
|
|
|
|
|
const toNumberList = args => args.split(",").map(parseFloat);
|
|
|
|
|
const applyFunction = (fn, args) =>
|
|
|
|
|
spreadsheetFunctions[fn.toLowerCase()](toNumberList(args));
|
|
|
|
|
return str2.replace(
|
|
|
|
|
regex,
|
|
|
|
|
(match, fn, args) =>
|
|
|
|
|
spreadsheetFunctions.hasOwnProperty(fn.toLowerCase()) ? applyFunction(fn, args) : match
|
|
|
|
|
);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const range = (start, end) =>
|
|
|
|
|
start > end ? [] : [start].concat(range(start + 1, end));
|
|
|
|
|
|
|
|
|
|
const charRange = (start, end) =>
|
|
|
|
|
range(start.charCodeAt(0), end.charCodeAt(0)).map(x =>
|
|
|
|
|
String.fromCharCode(x)
|
|
|
|
|
);
|
|
|
|
|
|
|
|
|
|
const evalFormula = x => {
|
|
|
|
|
const rangeRegex = /([A-J])([1-9][0-9]?):([A-J])([1-9][0-9]?)/gi;
|
|
|
|
|
const rangeFromString = (n1, n2) => range(parseInt(n1), parseInt(n2));
|
|
|
|
|
const elemValue = n => c => document.getElementById(c + n).value;
|
|
|
|
|
const addChars = c1 => c2 => n => charRange(c1, c2).map(elemValue(n));
|
|
|
|
|
const varRangeExpanded = x.replace(rangeRegex, (_, c1, n1, c2, n2) =>
|
|
|
|
|
rangeFromString(n1, n2).map(addChars(c1)(c2))
|
|
|
|
|
);
|
|
|
|
|
const varRegex = /[A-J][1-9][0-9]?/gi;
|
|
|
|
|
const varExpanded = varRangeExpanded.replace(
|
|
|
|
|
varRegex,
|
|
|
|
|
match => document.getElementById(match.toUpperCase()).value
|
|
|
|
|
);
|
|
|
|
|
const functionExpanded = applyFn(varExpanded);
|
|
|
|
|
return functionExpanded === x
|
|
|
|
|
? functionExpanded
|
|
|
|
|
: evalFormula(functionExpanded);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</script>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
### Before Test
|
|
|
|
|
<div id='html-setup'>
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<!DOCTYPE html>
|
|
|
|
|
<html lang="en">
|
|
|
|
|
<head>
|
|
|
|
|
<meta charset="UTF-8">
|
|
|
|
|
<title>Spreadsheet</title>
|
|
|
|
|
<style>
|
|
|
|
|
#container {
|
|
|
|
|
display: grid;
|
|
|
|
|
grid-template-columns: 50px repeat(10, 200px);
|
|
|
|
|
grid-template-rows: repeat(11, 30px);
|
|
|
|
|
}
|
|
|
|
|
.label {
|
|
|
|
|
background-color: lightgray;
|
|
|
|
|
text-align: center;
|
|
|
|
|
vertical-align: middle;
|
|
|
|
|
line-height: 30px;
|
|
|
|
|
}
|
|
|
|
|
</style>
|
|
|
|
|
</head>
|
|
|
|
|
<body>
|
|
|
|
|
<div id="container">
|
|
|
|
|
<div></div>
|
|
|
|
|
</div>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
### After Test
|
|
|
|
|
<div id='html-teardown'>
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
</body>
|
|
|
|
|
</html>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Solution
|
|
|
|
|
<section id='solution'>
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<script>
|
|
|
|
|
const infixToFunction = {
|
|
|
|
|
"+": (x, y) => x + y,
|
|
|
|
|
"-": (x, y) => x - y,
|
|
|
|
|
"*": (x, y) => x * y,
|
|
|
|
|
"/": (x, y) => x / y
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const infixEval = (str, regex) =>
|
|
|
|
|
str.replace(regex, (_, arg1, fn, arg2) =>
|
|
|
|
|
infixToFunction[fn](parseFloat(arg1), parseFloat(arg2))
|
|
|
|
|
);
|
|
|
|
|
|
|
|
|
|
const highPrecedence = str => {
|
|
|
|
|
const regex = /([0-9.]+)([*\/])([0-9.]+)/;
|
|
|
|
|
const str2 = infixEval(str, regex);
|
|
|
|
|
return str === str2 ? str : highPrecedence(str2);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const spreadsheetFunctions = {
|
|
|
|
|
"": x => x
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const applyFn = str => {
|
|
|
|
|
const noHigh = highPrecedence(str);
|
|
|
|
|
const infix = /([0-9.]+)([+-])([0-9.]+)/;
|
|
|
|
|
const str2 = infixEval(noHigh, infix);
|
|
|
|
|
const regex = /([a-z]*)\(([0-9., ]*)\)(?!.*\()/i;
|
|
|
|
|
const toNumberList = args => args.split(",").map(parseFloat);
|
|
|
|
|
const applyFunction = (fn, args) =>
|
|
|
|
|
spreadsheetFunctions[fn.toLowerCase()](toNumberList(args));
|
|
|
|
|
return str2.replace(
|
|
|
|
|
regex,
|
|
|
|
|
(match, fn, args) =>
|
|
|
|
|
spreadsheetFunctions.hasOwnProperty(fn.toLowerCase()) ? applyFunction(fn, args) : match
|
|
|
|
|
);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
const range = (start, end) =>
|
|
|
|
|
start > end ? [] : [start].concat(range(start + 1, end));
|
|
|
|
|
|
|
|
|
|
const charRange = (start, end) =>
|
|
|
|
|
range(start.charCodeAt(0), end.charCodeAt(0)).map(x =>
|
|
|
|
|
String.fromCharCode(x)
|
|
|
|
|
);
|
|
|
|
|
|
|
|
|
|
const evalFormula = x => {
|
|
|
|
|
const rangeRegex = /([A-J])([1-9][0-9]?):([A-J])([1-9][0-9]?)/gi;
|
|
|
|
|
const rangeFromString = (n1, n2) => range(parseInt(n1), parseInt(n2));
|
|
|
|
|
const elemValue = n => c => document.getElementById(c + n).value;
|
|
|
|
|
const addChars = c1 => c2 => n => charRange(c1, c2).map(elemValue(n));
|
|
|
|
|
const varRangeExpanded = x.replace(rangeRegex, (_, c1, n1, c2, n2) =>
|
|
|
|
|
rangeFromString(n1, n2).map(addChars(c1)(c2))
|
|
|
|
|
);
|
|
|
|
|
const varRegex = /[A-J][1-9][0-9]?/gi;
|
|
|
|
|
const varExpanded = varRangeExpanded.replace(
|
|
|
|
|
varRegex,
|
|
|
|
|
match => document.getElementById(match.toUpperCase()).value
|
|
|
|
|
);
|
|
|
|
|
const functionExpanded = applyFn(varExpanded);
|
|
|
|
|
return functionExpanded === x
|
|
|
|
|
? functionExpanded
|
|
|
|
|
: evalFormula(functionExpanded);
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
window.onload = () => { };
|
|
|
|
|
</script>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</section>
|
