Provides a front end for Javascript / Typescript AST generation by Babel parser with TyphonJS plugin support.
npm install @typhonjs/babel-parser
Provides a front end for Javascript / Typescript AST generation by Babel parser with TyphonJS plugin support. By default all Babel parser plugins are enabled except for flow and there is a handy override mechanism to change relevant defaults without having to provide a full set of options to the parser.
This NPM module can be installed as a dependency in package.json as follows:
``js`
"dependencies": {
"@typhonjs/babel-parser": "^0.2.0"
}
Please see Babel Parser Docs for specific plugin information. By default babel-parser enables all plugins except for flow as it is incompatible with the typescript plugin. Also by default the decorators plugins is enabled and not compatible with decorators-legacy.
The default Babel parser options is as follows:
`
const s_DEFAULT_BABELPARSER_OPTIONS =
{
plugins: ['asyncGenerators', 'bigInt', 'classProperties', 'classPrivateProperties', 'classPrivateMethods',
['decorators', { decoratorsBeforeExport: false }], 'doExpressions', 'dynamicImport',
'exportDefaultFrom', 'exportNamespaceFrom', 'functionBind', 'functionSent', 'importMeta',
'jsx', 'logicalAssignment', 'nullishCoalescingOperator', 'numericSeparator', 'objectRestSpread',
'optionalCatchBinding', 'optionalChaining', ['pipelineOperator', { proposal: 'minimal' }], 'throwExpressions',
'typescript']
};
There is a way to provide additional override directives to babel-parser which modifies the default babel parser options above. This only activates when no manual parser options are provided. A third parameter can be passed into parse which will modify the default parameters above. For example Flow is supported by passing in { flow: true } as the override object. This allows flow to be enabled and typescript to be disabled without providing the full babel parser options manually. A few other optional overrides are available:
`
{
decoratorsBeforeExport:
decoratorsLegacy: true, // Removes the proposal decorators plugin for
flow: true, // Enables flow / disables typescript plugins
pipelineOperatorProposal:
}
An ES6 example follows:
`js
import BabelParser from '@typhonjs/babel-parser';
// Basic usage to parse text / source code with default options.
const ast = BabelParser.parse();
// Providing custom options
const parserOptions = { plugins: [
const ast = BabelParser.parse(, parserOptions);
// Basic usage with default options, but with an override to disable Typescript and enable Flow plugins
const ast = BabelParser.parse(, void 0, { flow: true });`
@typhonjs/babel-parser may be loaded as a TyphonJS plugin with typhonjs-plugin-manager and if an eventbus is associated the following event categories are registered:
typhonjs:babel:parser:parse - invokes BabelParser.parse`