Exercise 1: Workspace, Project, Target, Scheme — Possible Solution
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TASK
Explain the relationship between a workspace, a project, a target and a
scheme, using one imaginary app that has a widget extension.

ANSWER
Imagine an app called Notes with a widget.

- The PROJECT holds the files and settings for building the products. Here
  it holds two targets.
- A TARGET is one product. Notes has an app target and a widget extension
  target, each with its own build settings and configurations.
- A SCHEME says which targets to build, which configuration to use, and
  which tests to run. One scheme could build the app and the widget in
  Debug; another could build them in Release. Only one scheme is active at
  a time.
- A WORKSPACE groups projects. If Notes also depends on a separate project
  of shared code, a workspace could contain both, and they would build in the
  same workspace build directory.

CHECK
Every term above appears in the chapter's definitions. The Notes example is
illustrative and not from a source.