ranlexer
Tiny JavaScript parser and generator
Install
Using npm:
npm install ranlexer --saveUsage
ranlexer can export the following methods
- parse: Parse the code into an ast
- walk: Walk through the structure of the ast to perform custom operations
- generate: Parse the ast into code
- build: A lightweight build tool that supports treeshaking
parse
Parse the code into an ast:
import { parse } from 'ranlexer'
const code = 'let a = 1;'
const ast = parse(code)walk
Walk through the structure of the ast to perform custom operations
There are two options：
- ast: ast structure node
- opts: One object with two methods in it
// Export the type of the ast node
import type { Types } from 'ranlexer'
const opts = {
enter: (node: Types.Node) => {
// Enter the processing of the node
},
leave: (node: Types.Node) => {
// Leave the node processing
}
walk(ast, opts)generate
Parse the ast into code:
import { generate } from 'ranlexer'
const ast = {
type: NodeType.Program,
start: 0,
end: 9,
body: [
{
type: NodeType.VariableDeclaration,
start: 0,
end: 9,
declarations: [
{
type: NodeType.VariableDeclarator,
id: {
type: NodeType.Identifier,
name: 'a',
start: 4,
end: 5,
},
start: 4,
end: 9,
init: {
type: NodeType.Literal,
value: '1',
raw: '1',
start: 8,
end: 9,
},
},
],
kind: 'let',
},
],
}
const code = generate(ast) // 'let a = 1;'build
A lightweight build tool that supports treeshaking
import { build } from 'ranlexer'
const bundle = await build(option)Generate a bundle by passing in options，All options are well, optional:
-
input: Build entry, if not set, the default value is
./index.js -
output: Path to the build output file. If not set, the default value is
./dist/index.js - external: String array，the modules in the array are not built
The bundle has two methods:
- generate: generate is to output the built code directly,
import { build } from 'ranlexer'
const bundle = await build(option)
const code = bundle.generate()- write: write is to output the file to a directory.
import { build } from 'ranlexer'
const bundle = await build(option)
bundle.write()