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    <p>Note that this can be done much more elegantly without the <code>toString</code> / <code>c.parse</code> business:</p> <pre><code>import scala.language.experimental.macros abstract class Model { def toMap[T]: Map[String, Any] = macro Macros.toMap_impl[T] } object Macros { import scala.reflect.macros.Context def toMap_impl[T: c.WeakTypeTag](c: Context) = { import c.universe._ val mapApply = Select(reify(Map).tree, newTermName("apply")) val pairs = weakTypeOf[T].declarations.collect { case m: MethodSymbol if m.isCaseAccessor =&gt; val name = c.literal(m.name.decoded) val value = c.Expr(Select(c.resetAllAttrs(c.prefix.tree), m.name)) reify(name.splice -&gt; value.splice).tree } c.Expr[Map[String, Any]](Apply(mapApply, pairs.toList)) } } </code></pre> <p>Note also that you need the <code>c.resetAllAttrs</code> bit if you want to be able to write the following:</p> <pre><code>User("a", 1, Nil).toMap[User] </code></pre> <p>Without it you'll get a confusing <code>ClassCastException</code> in this situation.</p> <p>By the way, here's a trick that I've used to avoid the extra type parameter in e.g. <code>user.toMap[User]</code> when writing macros like this:</p> <pre><code>import scala.language.experimental.macros trait Model object Model { implicit class Mappable[M &lt;: Model](val model: M) extends AnyVal { def asMap: Map[String, Any] = macro Macros.asMap_impl[M] } private object Macros { import scala.reflect.macros.Context def asMap_impl[T: c.WeakTypeTag](c: Context) = { import c.universe._ val mapApply = Select(reify(Map).tree, newTermName("apply")) val model = Select(c.prefix.tree, newTermName("model")) val pairs = weakTypeOf[T].declarations.collect { case m: MethodSymbol if m.isCaseAccessor =&gt; val name = c.literal(m.name.decoded) val value = c.Expr(Select(model, m.name)) reify(name.splice -&gt; value.splice).tree } c.Expr[Map[String, Any]](Apply(mapApply, pairs.toList)) } } } </code></pre> <p>Now we can write the following:</p> <pre><code>scala&gt; println(User("a", 1, Nil).asMap) Map(name -&gt; a, age -&gt; 1, posts -&gt; List()) </code></pre> <p>And don't need to specify that we're talking about a <code>User</code>.</p>
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    1. POScala Macros: Making a Map out of fields of a class in Scala
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    1. COWhy resetAllAttrs? Looks like it shouldn't be necessary here.
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    2. COIt works without resetAllAttrs. Thanks for the great answer. One thing though, your implementation only outputs vals that are defined in the constructor (i.e. case accessor). I used isAccessor instead. I seem to have missed that method before.
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    3. COAh, right—I've removed the `resetAllAttrs` in the second example (it definitely is necessary in the first, though). And I wasn't sure about non-case class members, since `numPosts` doesn't appear in your desired output, for example.
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