babel-plugin-import-glob

babel-plugin-import-glob

Babel plugin to enable importing modules using a glob pattern. Tested with Node.js 4 and above.

Installation

npm install --save-dev babel-plugin-import-glob

Then add import-glob to your .babelrc file, like:

{
  "plugins": ["import-glob"]
}

Usage

This plugin is useful if you have multiple modules but you don't want to import them one at a time.

Maybe you're using the handlebars-inline-precompile plugin and are putting your modules in a templates directory. Or you need to dynamically reference one out of several classes and don't want to maintain the lookup by hand. Perhaps you need to load multiple modules for their side-effects and wish to simply add them to a directory without additional work. If so, this plugin is for you!

Of course in the vast majority of cases you should just use normal import statements. Don't go overboard using this plugin.

You can import the default members of any matching module. Let's say you have a directory layout like this:

• index.js
• templates/main.handlebars.js
• templates/_partial.handlebars.js

In index.js you can write:

import { main, _partial } from './templates/**/*.handlebars.js'

You can add an optional glob: prefix:

import { main, _partial } from 'glob:./templates/**/*.handlebars.js'

You can alias members:

import { main, _partial as partial } from './templates/**/*.handlebars.js'

Or import all matches into a namespace object:

import * as templates from './templates/**/*.handlebars.js'
// Provides `templates.main` and `templates._partial`

Note that you cannot import the default from the glob pattern. The following won't work and throws a SyntaxError:

import myTemplates from './templates/**/*.handlebars.js' // This will throw a SyntaxError

You can load modules for their side-effects though:

import './modules-with-side-effects/*.js'

Glob patterns

The plugin uses the glob package. Please refer to its documentation regarding the pattern syntax.

The glob pattern must be relative. It must start with ./ or ../. A SyntaxError is thrown otherwise.

Import members

Identifiers are generated for all matches using the dynamic portions of the pattern. File-separators in the resulting strings are replaced by dollar signs. The strings are then converted into identifiers.

A valid identifier cannot always be generated. If that's the case a SyntaxError is thrown with more details. Similarly multiple matches may result in the same identifier. This also results in a SyntaxError being thrown.

For the ./templates/**/*.handlebars.js example above the matches are:

• ./templates/main.handlebars.js
• ./templates/_partial.handlebars.js

The dynamic portions are main and _partial. These are valid identifiers and therefore used as the import members.

A SyntaxError is throw when importing a member that does not correspond to a match:

import { doesNotExist } from './templates/**/*.handlebars.js' // This will throw a SyntaxError

Here's an overview of how the members are determined for additional matches:

Match	Result	Reason
./templates/terms-and-conditions.handlebars.js	termsAndConditions	The - cannot be used in the identifier so it's removed. The following character is uppercased
./templates/blog/footer.handlebars.js	blog$footer	The blog directory is captured by the ** expression in the pattern. It is joined with the footer name using a dollar sign
./templates/-main.handlebars.js	SyntaxError	The - is removed, resulting in the same identifier as for main.handlebars.js
./templates/new.handlebars.js	_new	new is a reserved word so it's prefixed with an underscore
./templates/blog/new.handlebars.js	blog$new	Even though new is a reserved word, it's combined with blog$ so no prefix is necessary
./templates/404.handlebars.js	_404	Identifiers can't start with digits so it's prefixed with an underscore
./templates/error-pages/404.handlebars.js	errorPages$404	Now that 404 is combined with errorPages$ it no longer needs to be prefixed
./templates/🙊.handlebars.js	SyntaxError	No identifier can be generated for 🙊

Brace expansions are not considered to be a dynamic portion of the pattern. Given the pattern ./templates/{blog,error-pages}/*.handlebars.js:

Match	Result
./templates/blog/footer.handlebars.js	footer
./templates/error-pages/404.handlebars.js	_404

Use parentheses patterns instead, e.g. ./templates/{@(blog),@(error-pages)}/*.handlebars.js:

Match	Result
./templates/blog/footer.handlebars.js	blog$footer
./templates/error-pages/404.handlebars.js	errorPages$404