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POIs there a way to create transform two equivalent types in Scala reflection into two equal types?
 

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  1. POIs there a way to create transform two equivalent types in Scala reflection into two equal types?
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    <p>Consider the following:</p> <pre><code>scala&gt; import scala.reflect.runtime.universe._ import scala.reflect.runtime.universe._ scala&gt; typeOf[Boolean] res23: reflect.runtime.universe.Type = Boolean scala&gt; typeOf[scala.Boolean] res24: reflect.runtime.universe.Type = Boolean scala&gt; res23 == res24 res25: Boolean = true scala&gt; typeOf[java.lang.Boolean] res26: reflect.runtime.universe.Type = Boolean scala&gt; res23 == res26 res27: Boolean = false scala&gt; class Foo { def bf(arg: Boolean) = ??? } defined class Foo scala&gt; typeOf[Foo] res28: reflect.runtime.universe.Type = Foo scala&gt; res28.member(newTermName("bf")).asMethod res30: reflect.runtime.universe.MethodSymbol = method bf scala&gt; res30.paramss.head.head res31: reflect.runtime.universe.Symbol = value arg scala&gt; res31.typeSignature res32: reflect.runtime.universe.Type = scala.Boolean scala&gt; res32 == res23 res33: Boolean = false scala&gt; res32 =:= res23 res37: Boolean = true </code></pre> <p>So the type obtained via the typeOf[Boolean] function is equivalent to the type obtained via inspecting a method, but it is not equal.</p> <p>Is there a way to transform two equivalent types into some canonical representation where the results will be equal? I'd like to be able to use them for things like keys in maps.</p> <h2>Edit:</h2> <p>To be more clear, what I'm looking for is something along the lines of (not a real repl session):</p> <pre><code>scala&gt;val tp1 = // some type scala&gt;val tp2 = // equivalent type obtained another way scala&gt;tp1 == tp2 res1: Boolean = false scala&gt;tp1 =:= tp2 res2: Boolean = true scala&gt;val ctp1 = tp1.canonical scala&gt;val ctp2 = tp2.canonical scala&gt;ctp1 == ctp2 res3: Boolean = true scala&gt;ctp1 =:= tp1 res4: Boolean = true scala&gt;ctp2 =:= tp2 res5: Boolean = true </code></pre> <p>So equivalence is preserved by the transformation. I also need it to work on parameterized types.</p>
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    1. USErik Engbrecht
    1. USErik Engbrecht
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    2. VO
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    1. COI do not fancy trying to turn the elaborate hierarchy of `isSameType` machinations into a `hashCode`. So I would say _in general probably not_.
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      1. USRex Kerr
    2. COI don't see an easy way here either.
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      1. POIs there a way to create transform two equivalent types in Scala reflection into two equal types?
      1. USEugene Burmako
 

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