markdown-it-replace-it

This markdown-it plugin replaces the "replacements" feature in markdown-it typographer, allowing you to customize the replacement rules (regular expression substitutions) done to inline text outside of autolinks. The replacement text can also be interpreted as HTML.

There are four built-in replacement rules (mimicking some of the built-in markdown-it typographer):

• +- → ± (rule "plusminus")
• ... → … (rule "ellipsis")
• --- → — (rule "mdash")
• -- → – (rule "ndash")

Each rule can be turned off by specifying an option object when using the module (mapping each undesired rule name to false). Additional rules can be added by modifying the replacements module attribute. This is an array of rules, where each rule has:

• a name rule.name
• a regular expression rule.re pattern for searching the text to be replaced
• a substitution rule.sub that replaces the text matching the regular expression pattern. This can be either a string value or a function.
• a flag rule.html (default 'false') that instructs the renderer that the returned string is HTML
• a flag rule.default (default 'true') controlling if this rule is enabled

Sample Usage

Without smart quotes

md = require('markdown-it')()
.use(require('markdown-it-replacements'));
md.renderInline('Hello... "world"---');

// returning -> 'Hello… "world"—'

With smart quotes

md = require('markdown-it')({typographer: true})
.use(require('markdown-it-replacements'));
md.renderInline('Hello... "world"---');

// returning -> 'Hello… “world”—'

Using options to turn specific replacements on/off

md = require('markdown-it')({typographer: true})
.use(require('markdown-it-replacements'), {mdash: false});
md.renderInline('Hello... "world"---');

// returning -> 'Hello… “world”---'

Adding custom replacements

mir = require('markdown-it-replacements');
mir.replacements.push({
  name: 'allcaps',
  re: /[a-z]/g,
  sub: function (s) { return s.toUpperCase(); },
  default: true
});
md = require('markdown-it')({typographer: true}).use(mir);
md.renderInline('Hello... "world"---');

// returning -> 'HELLO… “WORLD”—'

Adding custom replacements with support for inline HTML

mir = require('markdown-it-replacements');
mir.replacements.push({
  name: 'allcaps',
  re: /[a-z]/g,
  html: true,
  sub: function (s) { return '<span>' + s.toUpperCase() + '</span>'; },
  default: true
});
md = require('markdown-it')({typographer: true}).use(mir);
md.renderInline('Hello... "world"---');

// returning -> '<span>HELLO</span>… “<span>WORLD</span>”—'

Notes

• Unlike the built-in replacements rule, this module does not require the global typographer option to be set to true. (The reasoning being that, if you're using this module, you probably want to do the substitutions.) This means that the typographer option effectively controls whether to do smart-quote substitution.
• This module was built on top the the markdown-it-replacements and:
  • upgraded the dependencies
  • returned to plain JavaScript (instead of CoffeeScript)
  • adding the inline HTML support
  • propagating the parser state environment to the substitution function. This environment is used by some frameworks or modules (like 11ty) to provide dynamic values during the markdown conversion.