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    <p>This question is answered in duplicate by Travis <a href="https://stackoverflow.com/a/18485004/1296806">here</a>. There are links to the issue in the tracker and to Eugene's discussion (in the comments and mailing list).</p> <p>In the famous "Skylla and Charybdis" section of the type checker, our hero decides what shall escape dark anonymity and see the light as a member of the structural type.</p> <p>There are a couple of ways to trick the type checker (which do not entail Odysseus's ploy of hugging a sheep). The simplest is to insert a dummy statement so that the block doesn't look like an anonymous class followed by its instantiation.</p> <p>If the typer notices that you're a public term that isn't referenced by the outside, it will make you private.</p> <pre><code>object Mac { import scala.language.experimental.macros import scala.reflect.macros.Context /* Make an instance of a structural type with the named member. */ def bar(name: String): Any = macro bar_impl def bar_impl(c: Context)(name: c.Expr[String]) = { import c.universe._ val anon = TypeName(c.freshName) // next week, val q"${s: String}" = name.tree val Literal(Constant(s: String)) = name.tree val A = TermName(s) val dmmy = TermName(c.freshName) val tree = q""" class $anon { def $A(i: Int): Int = 2 * i } val $dmmy = 0 new $anon """ // other ploys //(new $anon).asInstanceOf[{ def $A(i: Int): Int }] // reference the member //val res = new $anon //val $dmmy = res.$A _ //res // the canonical ploy //new $anon { } // braces required c.Expr(tree) } } </code></pre>
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    1. POGetting a structural type with an anonymous class's methods from a macro
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    1. USsom-snytt
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    1. COI'll just note that I actually provide the first workaround in this question itself (it's just un-quasiquoted here). I'm happy to have this answer wrap up the question—I think I'd been vaguely waiting for the bug to get fixed.
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      1. USTravis Brown
    2. CO@TravisBrown I bet you have other tools in your Bat Belt, too. Thx for the heads up: I assumed your AST was "the old extra braces trick", but I see now that the ClassDef/Apply are not wrapped in their own Block, as happens with `new $anon {}`. My other take-away is that in future I won't use `anon` in macros with quasiquotes, or similar special names.
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    3. COq"${s: String}" syntax gets delayed a bit, especially if you are using paradise. So more like next month rather than next week.
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      1. USDenys Shabalin
 

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