已删除：Scala 2 宏

过去实验性的宏系统已经被删除。

作为替代，现在有一个更干净、更受限的系统，它基于两个互补的概念：inline 与 '{ ... }/${ ... } 代码生成。 '{ ... } 延迟对代码的编译，并生成包含代码的对象， dually ${ ... } evaluates an expression which produces code and inserts it in the surrounding ${ ... }。 In this setting, a definition marked as inlined containing a ${ ... } is a macro, the code inside the ${ ... } is executed at compile-time and produces code in the form of '{ ... }. Additionally, the contents of code can be inspected and created with a more complex reflection API as an extension of '{ ... }/${ ... } framework.

• inline has been implemented in Scala 3.
• Quotes '{ ... } and splices ${ ... } has been implemented in Scala 3.
• TASTy reflect provides more complex tree based APIs to inspect or create quoted code.

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