Misc

sbt

• Projects -> Configurations -> Tasks
• Projects are contained in a directory project.in(file("core"))
  • file is same as java.io.File
• Configurations are like mini-projects with their own source directory and dependencies; for example, Compile and Test
  • Configurations can have dependencies between them. For example, Test configuration depends on Compile configuration
  • A special scope is Zero, when Configuration is not specified
• Tasks perform actions, can accept parameters, and are always executed v/s Settings which are evaluated only once
  • A special scope is Zero, when Task is not specified
• Projects, Configuration and Tasks are scope axis
• Project and Configuration names start with uppercase and tasks with lowercase
• All three scopes above can have settings
• sbt is a DAG that evaluates tasks and settings
• Scope delegation order
  • Task -> Zero -> Configuration -> Configuration Dependencies -> Zero -> Project -> ThisBuild -> Zero
  • Global is same as specifying Zero, Zero, Zero for project, configuration and task

Keys

• Settings and Tasks have Keys
• Custom Keys can be added by plugins
• 3 types of Keys: settingKey, taskKey and inputTaskKey
  • inputTaskKey are tasks that accept parameters, e.g. run takes main class name and other arguments