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|
Type in expressions to have them evaluated.
Type :help for more information.
scala> import language.experimental.macros
import language.experimental.macros
scala> import scala.reflect.macros.blackbox.Context
import scala.reflect.macros.blackbox.Context
scala>
scala> object Impls {
def foo(c: Context)(x: c.Expr[Int]) = {
import c.universe._
val body = Apply(Select(x.tree, TermName("$plus")), List(Literal(Constant(1))))
c.Expr[Int](body)
}
def bar(c: Context)(x: c.Expr[Int]) = {
import c.universe._
val body = Apply(Select(x.tree, TermName("$plus")), List(Literal(Constant(2))))
c.Expr[Int](body)
}
def quux(c: Context)(x: c.Expr[Int]) = {
import c.universe._
val body = Apply(Select(x.tree, TermName("$plus")), List(Literal(Constant(3))))
c.Expr[Int](body)
}
}
defined object Impls
scala> object Macros {
object Shmacros {
def foo(x: Int): Int = macro Impls.foo
}
def bar(x: Int): Int = macro Impls.bar
}; class Macros {
def quux(x: Int): Int = macro Impls.quux
}
defined object Macros
defined class Macros
scala>
scala> import Macros.Shmacros._
import Macros.Shmacros._
scala> println(foo(2) + Macros.bar(2) * new Macros().quux(4))
31
scala> :quit
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