Babel plugin to optionaly require modules. Useful with a bundler like Metro which doesn't support optional require
statements.
This is primarily useful if you want add an dependency to your library that's optional and you want users to be able to opt-out of it to save bundle size. You can also use it in apps to load configuration files only if they exist.
Install the plugin:
yarn add --dev babel-plugin-optional-require
Then include it in your .babelrc
:
{
"plugins": [
"optional-require"
]
}
builtins: boolean
: Whether to resolve Node builtins. Default:false
.blacklist: string[]
: List of modules we assume to be unavailable without resolving. Default:[]
.whitelist: string[]
: List of modules we assume to be available without resolving. Default:[]
.
To optionally require
a module, you need to wrap it in try/catch
:
let a;
try {
a = require('optional-module');
} catch (e) {
// Handle failure from loading the module
}
If the module optional-module
doesn't exist, the require
call will be replaced with an IIFE that throws an error, so you can catch it and handle it at runtime. Otherwise, the code is left unchanged.