babel-plugin-transform-undeclared-variables

babel-plugin-transform-undeclared-variables
===

A Babel transform to transform undeclared variables into a getter call or an import.

Note: undeclared variables on the left hand side of assignments are ignored.

``js
function template(data) {
return htmlA template ${literal};
}

// Would become
import html from './templateTag';

function template(data) {
return htmlA template ${data.literal};
}

`

Usage
---

Install the plugin with your favourite package manager. For example, with NPM:

`sh
npm install --save-dev babel-plugin-transform-last-statement
`

Then in your [Babel configuration][babel-configuration], add it to the list of plugins:

`js
{
plugins:['transform-undeclared-variables']
}
`

Options
---

By default, the transform will turn all undeclared variables into a getter call on the data object. You can configure:

- default: the default behaviour,
- variables: the behaviour for specific variables

`js
default: getter('variables: {
'': getter(''),
'': addImport('', {name: ''}).
'': function(path) {
// Do whatever you need to transform that specific identifier
}
}
`

Possible future work
---
- [ ] Allow configuration through non-JS babel configuration files, by allowing arrays instead of function calls
`json
{
"default": ["getter","otherObject"],
"variables": {
"undefinedVariable": ["addImport","package", {name: "exportName"}]
}
}
``
- [ ] Handle left side of assignments by creating a variable declaration automatically (type of declaration configurable).

[babel-configuration]: https://babeljs.io/docs/en/config-files