A note on the Swift 4 Package Manager Syntax

I ran into some issues setting up a new Swift 4 project from Swift Package Manager. Specifically, my main.swift file couldn’t import the dependencies I specified in my Package.swift file. It turns out, you have to import your dependencies in the root dependencies: section, then refer to them by module name in the targets() portion of the package.

// swift-tools-version:4.0
// The swift-tools-version declares the minimum version of Swift required to build this package.
import PackageDescription
let package = Package(
name: "nerdScrape",
dependencies: [
// Dependencies declare other packages that this package depends on.
// .package(url: /* package url */, from: "1.0.0"),
.package(url: "https://github.com/kylef/Commander", from: "0.6.0"),
],
targets: [
// Targets are the basic building blocks of a package. A target can define a module or a test suite.
// Targets can depend on other targets in this package, and on products in packages which this package depends on.
.target(
name: "nerdScrape",
dependencies: ["Commander"]
),
]
)
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Omitting the declaration in your target means the module won’t be available to your app and your import statements will generate compiler errors for nonexistent modules.