babel-plugin-defer-logic v0.0.1

Babel Plugin Defer Logic

JS equivalent of Golang's defer and Python's with statements.

Installation

yarn add --dev babel-plugin-defer-logic
# OR
npm install --save-dev babel-plugin-defer-logic

Setup

Add babel-plugin-defer-logic to your babel config's plugins section. Try to add it to the end so it runs the last transformations.

eg:

{
  "presets": ["@babel/preset", { "targets": { "node": 12 } }],
  "plugins": ["babel-plugin-defer-logic"]
}

Usage

This package converts the contents of defer calls to be in a function body's finally. Multiple arguments are supported and will be handled individually.

Function literals are supported, the body of the function is copied as a block to the finally part. Function references are treated as ordinary variables, so you'll have to do defer(myFunc()) instead of defer(myFunc)

You can however do

defer(() => {
  // This is good
})
defer(function() {
  // This is good
})
defer(async function() {
  // This is still good, as long as parent function is also an async function
})

More usages:

// From
function hello() {
  setIsLoading(true)
  defer(setIsLoading(false))
  // .. Do the work
}
// To
function hello() {
  try {
    setIsLoading(true)
    // .. Do the work
  } finally {
    setIsLoading(false)
  }
}

function hello() {
  try {
    setIsLoading(true)
    setIsConnected(false)
    defer(setIsLoading(false))
    defer(setIsConnected(true))
    // .. Do the work
  } catch (error) {
    console.log(error)
  }
}
// To
function hello() {
  try {
    try {
      setIsLoading(true)
      setIsConnected(false)
      // .. Do the work
    } catch (error) {
      console.log(error)
    }
  } finally {
    setIsLoading(false)
    setIsConnected(true)
  }
}

LICENSE

The contents of this package/repository are licensed under the terms of MIT License. See the LICENSE file for more info.