Extracting type from a reified, type-checked `Tree` in Scala -


given following repl session:

scala> import scala.reflect.runtime.universe._ import scala.reflect.runtime.universe._  scala> import scala.tools.reflect.toolbox import scala.tools.reflect.toolbox  scala> import scala.reflect.runtime.{currentmirror => cm} import scala.reflect.runtime.{currentmirror=>cm}  scala> val r = reify { val = 234.45 } r: reflect.runtime.universe.expr[unit] = expr[unit]({   val = 234.45;   () })  scala> val c = cm.mktoolbox().typecheck(r.tree) warning: there 1 feature warning; re-run -feature details c: qual$2.u.tree forsome { val qual$2: scala.tools.reflect.toolbox[reflect.runtime.universe.type] @scala.reflect.internal.annotations.uncheckedbounds } = {   val a: double = 234.45;   () }

what's recommended way of pulling out type of variable a type-checked tree c?

you can using quasiquotes, i'm not sure it's easiest way do:

scala> val c = cm.mktoolbox().typecheck(r.tree) warning: there 1 feature warning; re-run -feature details c: qual$2.u.tree forsome { val qual$2:     scala.tools.reflect.toolbox[reflect.runtime.universe.type]     @scala.reflect.internal.annotations.uncheckedbounds } = {   val a: double = 234.45;   () }  scala> val q"{val $name: $tpt = $rhs; ()}" = c name: reflect.runtime.universe.termname = tpt: reflect.runtime.universe.tree = double rhs: reflect.runtime.universe.tree = 234.45  scala> :t tpt.tpe reflect.runtime.universe.type  scala> println(tpt.tpe) double

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