@babel/plugin-proposal-do-expressions

What is @babel/plugin-proposal-do-expressions?

@babel/plugin-proposal-do-expressions is a Babel plugin that allows you to use 'do' expressions in your JavaScript code. 'Do' expressions enable you to use blocks of code as expressions, which can be particularly useful for complex conditional logic or for creating more readable code.

What are @babel/plugin-proposal-do-expressions's main functionalities?

Basic Do Expression

This feature allows you to use a block of code as an expression. In this example, the 'do' expression evaluates the conditional logic and assigns the result to the 'result' variable.

const result = do {
  if (x > 10) {
    'greater';
  } else {
    'lesser';
  }
};

Do Expression with Multiple Statements

This feature allows you to include multiple statements within a 'do' expression. Here, a temporary variable 'temp' is calculated and used within the conditional logic.

const result = do {
  let temp = x * 2;
  if (temp > 10) {
    'greater';
  } else {
    'lesser';
  }
};

Do Expression with Function Call

This feature demonstrates how you can include function calls within a 'do' expression. The 'calculate' function is defined and called within the 'do' block, and its result is assigned to the 'result' variable.

const result = do {
  function calculate(y) {
    return y * 2;
  }
  calculate(x);
};

Other packages similar to @babel/plugin-proposal-do-expressions

babel-plugin-transform-inline-environment-variables

This Babel plugin allows you to inline environment variables into your code. While it doesn't provide 'do' expressions, it offers a way to manage environment-specific configurations, which can be useful for conditional logic based on environment variables.

babel-plugin-macros

babel-plugin-macros allows you to create custom compile-time transformations. While it doesn't directly offer 'do' expressions, it provides a way to create custom syntax and transformations, which can be used to achieve similar goals.

README

@babel/plugin-proposal-do-expressions

Compile do expressions to ES5

See our website @babel/plugin-proposal-do-expressions for more information.

Install

Using npm:

npm install --save-dev @babel/plugin-proposal-do-expressions

or using yarn:

yarn add @babel/plugin-proposal-do-expressions --dev

Changelog

v7.25.9 (2024-10-22)

:bug: Bug Fix

• babel-parser, babel-template, babel-types
  • #16905 fix: Keep type annotations in syntacticPlaceholders mode (@liuxingbaoyu)
• babel-helper-compilation-targets, babel-preset-env
  • #16907 fix: support BROWSERSLIST{,_CONFIG} env (@JLHwung)
• Other
  • #16884 Analyze ClassAccessorProperty to prevent the no-undef rule (@victorenator)

:house: Internal

• babel-helper-transform-fixture-test-runner
  • #16914 remove test options flaky (@JLHwung)

:running_woman: Performance

• babel-parser, babel-types
  • #16918 perf: Make VISITOR_KEYS etc. faster to access (@liuxingbaoyu)