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<p>
  This is the home page of the project Kepler, an ongoing effort towards bringing compile-time metaprogramming to Scala.
  Our flavor of macros is reminiscent of Lisp macros, adapted to incorporate type safety and rich syntax.
  Unlike infamous C/C++ preprocessor macros, Scala macros: 1) are written in full-fledged Scala,
  2) work with expression trees, not with raw strings, 3) cannot change syntax of Scala.
</p>

<p>
  <b>Macros are functions that are called by the compiler during compilation</b>.
  Within these functions the programmer has access to compiler APIs.
  For example, it is possible to generate, analyze and typecheck code.
  You can learn more about macros from <a href="/documentation/index.html">documentation</a>.
</p>

<p>
  <b>Macros are shipping with the official Scala compiler</b>.
  Since 2.10.0 Scala includes macros that can be enabled
  with <code class="scala">import language.experimental.macros</code> on per-file basis
  or with <code class="scala">-language:experimental.macros</code> on per-compilation basis.
  Numerous commercial and research projects are already using macros.
</p>

<p>
  <b>Macros are good for code generation, static checks and domain-specific languages</b>,
  which makes them a tool of choice for a multitude of <a href="/usecases.html">real-world use cases</a>.
  Scenarios that traditionally involve writing and maintaining boilerplate can be addressed with macros in a concise and maintainable way.
  Therefore we believe that macros are a valuable asset to the Scala programming language.
</p>