scala 如何支持这种 sbt DSL 语法？

Question

我正在查看sbt 手册，我看到您可以设置项目并从 val 的名称推断位置。

lazy val util = (project in file("util")) 相当于 lazy val util = project 这怎么可能？

Answer 1

该宏

/**
 * Creates a new Project.  This is a macro that expects to be assigned directly to a val.
 * The name of the val is used as the project ID and the name of the base directory of the project.
 */
def project: Project = macro Project.projectMacroImpl

扩大

lazy val util = project

到

Project.apply("util", new File("util"))

查看 sbt 宏扩展以创建project/build.sbt文件的内容

scalacOptions ++= Seq("-Ymacro-debug-lite")