howprogrammingworks/datatypes

Built-in data types

Введение: типы данных

• Упражнения: Exercises.ru.md
• Примеры: JavaScript

datatypes's Issues

Assignment operators

Examples for: =, +=, -=, *=, /=, %=, **=, <<=, >>=, >>>=, &=, ^=, \|=
See MDN

Operator delete

See MDN

Min length in 3-by-reference.test

I have solution:

const inc = num => { ++num.n; };

and npm test print:

Test 3-by-reference
  Length: 19, lines: 1
  Error: Solution is too short

so need fix file: 3-by-reference.test, line: length: [19, 70],

npm test command broken

This "test": "eslint ./Exercises; hpw" doesn't work.
Running this command says:

[email protected] test
eslint ./Exercises; hpw
Oops! Something went wrong! :(

ESLint: 8.40.0

No files matching the pattern "./Exercises;" were found.
Please check for typing mistakes in the pattern.

Probably it should look like "eslint ./Exercises && hpw"
But in this case, I do not understand the presence of "ci": "eslint ./Exercises && hpw"
Can anyone explain the proper way to test my exercises?

https://github.com/HowProgrammingWorks/DataTypes/blob/2695aaceec7efaefd07538b6e4aec3764bef86ac/package.json#LL8C16-L8C16

Bitwise operators

Examples for: &, |, ^, ~, <<, >>, >>>
See MDN

Null type checks is not considered by the tests length

There is a problem with countTypesInArray function (4-count-types.js). The tests require a solution to be 200 signs max, but in this case, we kinda lose the check for nulls.

As you know null in JavaScript has a type of object. Thus, the implementation you require will count objects but not nulls. So, the function is not suitable for checking all the JS types.

I clearly understand that such a check can be done using a ternary operator but it's not convenient and intuitive enough.

The implementation below considers this JS's quirk:

const data = [
  false,
  'a',
  22,
  'hey',
  undefined,
  42,
  12,
  true,
  { a: 12 },
  { name: 'Jack' },
  'foo',
  'bar',
  true,
  null,
  undefined,
  Symbol('a'),
  null
];

const countTypesInArray = data => {
  const h = {};
  for (const item of data) {
    if (typeof item === 'object' && item === null) {
      h['null'] = 1;

      if (h['null'] > 0) {
        h['null']++;
      }
    } else if (typeof item in h) {
      h[typeof item]++;
    } else {
      h[typeof item] = 1;
    }
  }
  return h;
};

console.log(countTypesInArray(data));

So, maybe you should consider an option for making tests a little bit more loose for null checks.

Arithmetic operators

Examples for: +, -, *, /, %, ++, --, **
See MDN