Pre-SIP: A Syntax for Collection Literals

[Sporarum]

@lihaoyi

Another example is from uPickle, which lets you define JSON literals as follows:

[…]

This would look a lot nicer if written with square brackets

val json: ujson.Value = [
  "declarationMap" -> true,
  "esModuleInterop" -> true,
  "baseUrl" -> ".",
  "rootDir" -> "typescript",
  "declaration" -> true,
  "outDir" -> pubBundledOut(),
  "plugins" -> [
    ["transform" -> "typescript-transform-paths"],
    [
      "transform" -> "typescript-transform-paths",
      "afterDeclarations" -> true
    ]
  ],
  "moduleResolution" -> "node",
  "module" -> "CommonJS",
  "target" -> "ES2020"
]

See Syntax highlighting inside custom string, it would read even better as:

val json = json"""

{
  "declarationMap": true,
  "esModuleInterop": true,
  "baseUrl": ".",
  "rootDir": "typescript",
  "declaration": true,
  "outDir": ${pubBundledOut()},
  "plugins": [
    {"transform": "typescript-transform-paths"},
    {
      "transform": "typescript-transform-paths",
      "afterDeclarations": true
    }
  ],
  "moduleResolution": "node",
  "module": "CommonJS",
  "target": "ES2020"
}

"""