string-remove-widows^4.0.3

Installation

Quick Take

Examples

• Widow word removal from text within HTML

Idea

This library takes a string and removes widow words, by replacing last space in the paragraph with non-breaking space.

• Not just adds but if want, removes widow word prevention measures
• Tackles both paragraphs and single lines
• Recognises existing measures and if found, skips operation
• Option to encode for HTML, CSS or JS strings or put a raw non-breaking space
• Does not mangle the line endings (Mac LF, Old style CR or Windows-style CR LF)
• A customisable minimum amount of words per line/paragraph to trigger widow word removal
• Can be used in different stages of the workflow: before HTML/CSS/JS-encoding or after
• Optionally replaces spaces with non-breaking spaces in front of all kinds of dashes
• Optionally replaces spaces with non-breaking spaces within UK postcodes
• Optionally it can skip content between templating tags, for example, Nunjucks {{ and }} — presets are given for Jinja, Nunjucks, Liquid, Hexo and Hugo

API — removeWidows()

The main function removeWidows() is imported like this:

It’s a function which takes three input arguments:

The Optional Options Object has the following shape:

Here are all defaults in one place for copying:

The function will return a plain object (Res type above):

for example, here’s how the output could look like:

{
  res: "Lorem ipsum dolor sit amet",
  ranges: [
    [21, 27, " "]
  ],
  log: {
    timeTakenInMilliseconds: 42
  },
  whatWasDone: {
    removeWidows: true,
    convertEntities: false
  }
}

API — defaults

You can import defaults:

It's a plain object:

The main function calculates the options to be used by merging the options you passed with these defaults.

API — version

You can import version:

opts.targetLanguage

Not all text ends up in HTML. As you know, you can inject the content via CSS pseudo attributes and also text might be prepared to be pasted into JSON.

This program allows you to customise the target encoding for chosen language: html, css or js.

Here’s an HTML with HTML-encoded non-breaking space:

Some raw text in a very long line.

Here’s CSS analogue:

span:before {
  content: "Some raw text in a very long\00A0line.";
}

Here’s JavaScript analogue:

alert("Some raw text in a very long\u00A0line.");

For example, a minimal application would look like this:

import { removeWidows } from "string-remove-widows";
// second input argument is a plain object, the Optional Options Object:
const result = removeWidows("Some raw text in a very long line.", {
  targetLanguage: "css",
});
// now the widow words will be prevented considering that content will go to CSS content:
console.log(result);
// => "Some raw text in a very long\00A0line."

opts.ignore

Very often text already contains templating language literals.

For example, this Nunjucks snippet:

Hi{% if data.firstName %} data.firstName{% endif %}!

We intend to either say Hi John! to customer John or just Hi! if we don’t know the customer’s name.

But if we run widow words removal on this piece of text, we don’t want   inserted into the middle of endif:

Hi{% if data.firstName %} data.firstName{% endif %}!
                                                ^^^^^^

That’s where opts.ignore comes in. You can list heads/tails (chunks from which to start ignoring/where to stop) manually:

import { removeWidows } from "string-remove-widows";
const result = removeWidows("Here is a very long line of text", {
  targetLanguage: "html",
  ignore: [
    {
      heads: "{{",
      tails: "}}",
    },
    {
      heads: ["{% if", "{%- if"],
      tails: ["{% endif", "{%- endif"],
    },
  ],
});

or you can just pick a template:

all
jinja
nunjucks
liquid
hugo
hexo

for example:

import { removeWidows } from "string-remove-widows";
const result = removeWidows("Here is a very long line of text", {
  targetLanguage: "html",
  ignore: "jinja",
});

If you want widest support of literals, all languages at once, put “all”.

opts.tagRanges

Sometimes input string can contain HTML tags. We didn’t go that far as to code up full HTML tag recognition, more so that such thing would duplicate already existing libraries, namely, string-strip-html.

opts.tagRanges accepts known HTML tag ranges (or, in fact, any “black spots” to skip):

import { stripHtml } from "string-strip-html";
import { removeWidows } from "string-remove-widows";

const input = `something in front here <a style="display: block;">x</a> <b style="display: block;">y</b>`;
// first, gung-ho approach - no tag locations provided:
const res1 = removeWidows(input).res;
console.log(res1);
// => something in front here <a style="display: block;">x</a> <b style="display:&nbsp;block;">y</b>
//                                                                               ^^^^^^
//                                      notice how non-breaking space is wrongly put inside the tag
//
// but, if you provide the tag ranges, program works correctly:
const tagRanges = stripHtml(input, { returnRangesOnly: true });
console.log(JSON.stringify(knownHTMLTagRanges, null, 4));
// => [[24, 51], [52, 56], [57, 84], [85, 89]]
// now, plug the tag ranges into opts.tagRanges:
const res2 = removeWidows(input, { tagRanges }).res;
console.log(res2);
// => something in front here <a style="display: block;">x</a>&nbsp;<b style="display: block;">y</b>

Compared to competition

	This program, string-remove-widows	widow-js	@simmo/widower
	Can both add and remove nbsps
Can both add and remove nbsps	✅	❌	❌
	Option to choose between raw, HTML, CSS or JS-encoded nbsps
Option to choose between raw, HTML, CSS or JS-encoded nbsps	✅	❌	❌
	Can replace spaces in front of hyphens, n- and m-dashes
Can replace spaces in front of hyphens, n- and m-dashes	✅	❌	❌
	Can prepare UK postcodes
Can prepare UK postcodes	✅	❌	❌
	Does not mangle different types of line endings (LF, CRLF, CR)
Does not mangle different types of line endings (LF, CRLF, CR)	✅	✅	✅
	Customisable minimal word count threshold
Customisable minimal word count threshold	✅	✅	❌
	Customisable minimal character count threshold
Customisable minimal character count threshold	✅	❌	❌
	Progress reporting function for web worker web apps
Progress reporting function for web worker web apps	✅	❌	❌
	Reports string index ranges of what was done
Reports string index ranges of what was done	✅	❌	❌
	Non-breaking space location’s whitespace does not necessarily have to be a single space
Non-breaking space location’s whitespace does not necessarily have to be a single space	✅	❌	❌
	Presets for Jinja, Nunjucks, Liquid, Hugo and Hexo templating languages
Presets for Jinja, Nunjucks, Liquid, Hugo and Hexo templating languages	✅	❌	❌
	Decoupled API^
Decoupled API^	✅	❌	✅
	CommonJS build
CommonJS build	✅	❌	✅
	ES Modules build
ES Modules build	✅	❌	❌
	UMD build for browser
UMD build for browser	✅	✅	❌
	Can process live DOM of a web page
Can process live DOM of a web page	❌	✅	❌
	Licence
Licence	MIT	ISC	MIT

^ A decoupled API means that at its core, the program is a function ”string-in, string-out“ and is not coupled with DOM, file I/O, network or other unrelated operations. Such API makes it easier to test and create many different applications on top of a decoupled API.

For example, our competitor widow.js has two coupled parts: 1. API which does string-in, string-out, and 2. DOM processing functions. It could have been two npm libraries. In the end, people who don’t need DOM operations can’t use it.

One decoupled, ”string-in, string-out“ library like string-remove-widows might power all these at once:

• Web page DOM-manipulation library
• a CLI application to process files or piped streams
• an Express REST endpoint on a server,
• a serverless lambda on AWS,
• an Electron desktop program

Changelog