Overview

lang is a suite of tools for ease of use checks against common practices that are otherwise a much longer check. Often times we find ourselves doing this check over and over:

if (item !== undefined && item !== null && item !== '') {};

Lang tools look to simplify that in several different ways. In the above case, you can simply use lang.isNullish() to check for all of those things at once:

import * as lang from '@flippydisk/tools/lib/lang';

if (!lang.isNullish(item)) {};

Alternatively, you can also get the individual items only if you do not want the entire suite:

import filterHTMLTags from '@flippydisk/tools/lib/utils/lang/filterHTMLTags';

• Supported methods are:
  • isEmptyString() {returns Boolean}
  • isUndefined() {returns Boolean}
  • isNumber() {returns Boolean}
  • isNull() {returns Boolean}
  • isNullish() {returns Boolean}
  • isStringy() {returns Boolean}
  • isEmptyObject() {returns Boolean}
  • getStringSafely() {returns String}
  • filterHTMLTags() {returns String}
  • getPropertySafely() {returns value of the property if it exists, or undefined}

Importing and Instantiation

Add @flippydisk/tools to your project. @flippydisk/tools is in the npm registry, so it should be as simple as the following:

npm i @flippydisk/tools --save-dev

However, if you run into any issues, or simply want a "main" branch version, you can alternatively add this manually to your package.json under the dependencies{} section:

"@flippydisk/tools": "git+ssh://git@github.com:flippydisk/tools.git"

Once it's in your project, you can either import all of the lang methods, or pick and choose. lang utilities are individual functions, so there is no instantiation needed.

import * as lang from '@flippydisk/tools/lang';

or as individual items:

import { isNull } from '@flippydisk/tools/lang';

Use

Add any Boolean method, like lang.isNumber(1), inline to any of your scripts and it will run the necessary checks (which vary based on the method you use) to return a Boolean value for the ease of use in an if check or switch case. Alternatively, there are also two methods that will return string values, with safety checks to avoid the NaN error when only using .toString(). Finally, there is also a method for stripping HTML tags and returning a string.

ex:

Boolean values:

- `lang.isEmptyString(''); // returns true`
- `lang.isEmptyString('something'); // returns false`
- `lang.isEmptyString(object.item); // returns false, as it is not a string`

String values:

- `lang.getStringSafely(1); // returns '1'`
- `lang.getStringSafely(true); // returns 'true'`
- `lang.getStringSafely(object.item); // returns string value of object.item`

HTML filtering:

const html = '<a href="flippydisk.com" class="MyClass">The words I want &amp; more.</a>';
- `lang.filterHTMLTags(html); // returns 'The words I want &amp; more.'`

Tests

lang/index.spec.js tests against all functions, objects, strings and boolean values to be defined, to be the correct typeof, and their expected values to be what they should be.

$ npm run test -- lang

> @flippydisk/tools@1.0.0 test
> cross-env npm run lint && jest "lang"

 PASS  src\lang\index.spec.js
  Lang
    √ will provide defaults on initialization (2ms)
    and its dependencies should
      √ be defined (3ms)
    functions should always return the correct result.
      √ isEmptyString should return Boolean (1ms)
      √ isUndefined should return Boolean (1ms)
      √ isNumber should return Boolean (1ms)
      √ isNull should return Boolean (1ms)
      √ isNullish should return Boolean with the leeway of also checking for null, undefined, NaN and empty strings (1ms)
      √ getStringSafely should return the string if it can decipher it, or null if it cant (1ms)
      √ isStringy should return the string if it can decipher it, or null if it cant (1ms)
      √ filterHTMLTags should return a string without any HTML tags (1ms)
      √ isEmptyObject should return a boolean value (1ms)

Test Suites: 1 passed, 1 total
Tests:       11 passed, 11 total
Snapshots:   0 total
Time:        0.953s, estimated 6s
Ran all test suites matching /lang/i.