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@babel/plugin-proposal-pipeline-operator

Installation​

npm install --save-dev @babel/plugin-proposal-pipeline-operator

Usage​

The pipeline operator has several competing proposals. Configure which proposal to use with the required "proposal" option. Its value is "hack" by default.

ValueProposal
"hack"Hack-style pipes
"fsharp"F#-style pipes with await

If "proposal" is omitted, or if "proposal": "hack" is used, then a "topicToken" option must be included. The topicToken must be one of "%", "^^", "@@", "^", or "#".

Examples​

The following examples use topicToken: "^^".

From react/scripts/jest/jest-cli.js.

JavaScript
// Status quo
console.log(
  chalk.dim(
    `$ ${Object.keys(envars)
      .map(envar => `${envar}=${envars[envar]}`)
      .join(' ')}`,
    'node',
    args.join(' ')
  )
);

// With pipes
Object.keys(envars)
  .map(envar => `${envar}=${envars[envar]}`)
  .join(' ')
  |> `$ ${^^}`
  |> chalk.dim(^^, 'node', args.join(' '))
  |> console.log(^^);

From jquery/src/core/init.js.

JavaScript
// Status quo
jQuery.merge( this, jQuery.parseHTML(
  match[ 1 ],
  context && context.nodeType ? context.ownerDocument || context : document,
  true
) );

// With pipes
context
  |> (^^ && ^^.nodeType ? ^^.ownerDocument || ^^ : document)
  |> jQuery.parseHTML(match[1], ^^, true)
  |> jQuery.merge(^^);

(For a summary of deprecated proposal modes’ behavior, see the pipe wiki’s table of previous proposals.)

With ^^ topic token:

babel.config.json
{
  "plugins": [
    ["@babel/plugin-proposal-pipeline-operator", { "topicToken": "^^" }]
  ]
}

With @@ topic token:

babel.config.json
{
  "plugins": [
    ["@babel/plugin-proposal-pipeline-operator", { "topicToken": "@@" }]
  ]
}

Via CLI​

Because this plugin requires a configuration option, it cannot be directly configured from the CLI. Use a config file instead with the CLI, to add and configure this plugin.

Via Node API​

With ^^ topic token:

JavaScript
require("@babel/core").transformSync("code", {
  plugins: [
    [ "@babel/plugin-proposal-pipeline-operator", { topicToken: "^^" } ],
  ],
});

With @@ topic token:

JavaScript
require("@babel/core").transformSync("code", {
  plugins: [
    [ "@babel/plugin-proposal-pipeline-operator", { topicToken: "@@" } ],
  ],
});