I am having trouble using Scala Macros. It keeps on telling me to
enable macro paradise to expand macro annotations
from the #compileTimeOnly message I wrote. I followed all the instructions from Macro annotation documentation and the SBT example.
IDE: IntelliJ 14.1
Scala version: 2.11.7
Build.scala under the Project folder:
import sbt._
import sbt.Keys._
object Build extends Build {
val paradiseVersion = "2.1.0-M5"
lazy val sm = Project(id = "server-modules", base = file(".")).settings(
version := "1.0",
logLevel := Level.Warn,
scalacOptions ++= Seq(),
scalaVersion := "2.11.7",
crossScalaVersions := Seq("2.10.2", "2.10.3", "2.10.4", "2.10.5", "2.11.0", "2.11.1", "2.11.2", "2.11.3", "2.11.4", "2.11.5", "2.11.6", "2.11.7"),
resolvers += Resolver.sonatypeRepo("snapshots"),
resolvers += Resolver.sonatypeRepo("releases"),
addCompilerPlugin("org.scalamacros" % "paradise" % paradiseVersion cross CrossVersion.full),
libraryDependencies <+= (scalaVersion)("org.scala-lang" % "scala-reflect" % _),
)
}
Code:
#compileTimeOnly("enable macro paradise to expand macro annotations")
class dmCompile extends StaticAnnotation{
def macroTransform(annottees: Any*): Any = macro DMCompile.impl
}
object DMCompile {
def impl(c: whitebox.Context)(annottees: c.Expr[Any]*): c.Expr[Any] = {
import c.universe._
Log.info("Work work work!")
c.Expr(q"""var x = y""")
}
}
#dmCompile class Test{}
What exactly am I missing?
This took me the entire day, but I got it working.
Simply disregard the SBT settings for macros paradise and manually add it in the Preference -> Scala Compiler
That's it!
For me a solution was to change Incrementality type from IDEA to SBT in the Settings. This allows to use native SBT's build engine instead of IDEA's one.
Related
I want to access the jquery ui library in my scala js project. I have tried defining the following main module:
import org.scalajs.jquery.JQueryStatic
import scala.scalajs.js
import org.scalajs.dom
import scalatags.JsDom.all._
import scala.scalajs.js.annotation.JSImport
#JSImport("jquery", JSImport.Namespace)
#js.native
object JQuery extends JQueryStatic
#js.native
trait JQueryUI extends JQueryStatic {
def spinner(options: js.Object = js.Dynamic.literal()): JQueryUI = js.native
}
#JSImport("jquery-ui", JSImport.Namespace)
#js.native
object JQueryUI extends JQueryUI
object App {
def main(args: Array[String]): Unit = {
dom.document.getElementById("root").appendChild(div(input(id := "input")).render)
JQuery("#input").asInstanceOf[JQueryUI].spinner()
}
}
And my build.sbt is as follows:
enablePlugins(ScalaJSBundlerPlugin)
lazy val opexCounter = project.in(file(".")).settings(
name := "Repro",
scalaVersion := "2.12.8",
libraryDependencies ++= Seq(
"org.scala-js" %%% "scalajs-dom" % "0.9.6",
"com.lihaoyi" %%% "scalatags" % "0.6.7",
"be.doeraene" %%% "scalajs-jquery" % "0.9.4"
),
npmDependencies in Compile ++= Seq(
"jquery" -> "2.2.1",
"jquery-ui" -> "1.12.1",
),
mainClass in Compile := Some("App"),
scalaJSUseMainModuleInitializer := true,
webpackDevServerPort := 3000
)
But when I load my page I get the following error in my console:
TypeError: qual$1.spinner is not a function
Is this not the correct way to import the library and if not what is?
The complete source for the project can be found here
I changed my npm dependency from jquery-ui to jquery-ui-bundle and imported it. I also had to make an explicit reference to my JQueryUIImport object in order to ensure it was instantiated. Those 2 changes fixed the problem
I have the snippet of test case below under src/test/scala:
package example.module
import utest._
object ModuleSpec extends TestSuite { ... }
... which compiles just fine with this snippet of build.sbt below:
val testDependencies: Seq[ModuleID] =
Seq(
"com.lihaoyi" %% "utest" % "0.6.5" % "test",
)
def testSettings: Seq[Setting[_]] =
Seq(
libraryDependencies ++= testDependencies)
lazy val root =
(project in file("."))
.aggregate(subproject)
lazy val subproject =
(project in file("subproject"))
.settings(testSettings: _*)
My question is:
Why the test code does not compile anymore if I add Test axis to libraryDependencies, like shown below?
def testSettings: Seq[Setting[_]] =
Seq(
libraryDependencies in Test ++= testDependencies)
In more detail:
The line containing import utest._ fails to compile, meaning that the dependency which is now declared as part of libraryDependencies in Test was ignored.
Argumentation:
Since I'm compiling a class under src/main/test, I would expect that libraryDependencies in Test would be the necessary and the sufficient piece of information in this case. In order words: I would not expect that a wider scope would be needed.
I have problem in using ScriptEngine from sbt 0.13.8
build.sbt
fork in run := true
scalaVersion := "2.11.6"
libraryDependencies ++= Seq(
"org.scala-lang" % "scala-compiler" % "2.11.6"
)
UseConfig.scala
object UseConfig {
def main(args: Array[String]) = {
import javax.script.ScriptEngineManager
val e = new ScriptEngineManager(null).getEngineByName("scala")
println(e)
}
}
and it prints null.
When I run a similar code in scala 2.11.6 console a scala engine is found successfully.
p.s. Is there are any other ways to compile dynamically scala code under sbt?
I'm trying to map over an HList in shapeless. The following example is derived from here:
import shapeless._
import poly._
object Main {
def main(args: Array[String]) = {
object choose extends (Set ~> Option) {
def apply[T](s : Set[T]) = s.headOption
}
val sets = Set(1) :: Set("foo") :: HNil
val opts = sets map choose // map selects cases of choose for each HList element
}
}
Unfortunately I am unable to compile the example. The compiler says "value map is not a member of HCons[scala.collection.immutable.Set[Int],HCons[scala.collection.immutable.Set[String],HNil]]". I suspect there is a missing import of an implicit that defines the map operation on HLists, but I don't know what that import should be. I'm using sbt with the following build.sbt file:
name := "scala-polymorphism-experiments"
version := "0.1.0"
scalaVersion := "2.10.3"
resolvers ++= Seq(
"Sonatype OSS Releases" at "http://oss.sonatype.org/content/repositories/releases/",
"Sonatype OSS Snapshots" at "http://oss.sonatype.org/content/repositories/snapshots/"
)
libraryDependencies ++= Seq("org.scalatest" % "scalatest_2.10" % "2.0" % "test",
"com.chuusai" % "shapeless" % "2.0.0-SNAPSHOT" cross CrossVersion.full changing())
I also have this problem if I use the M1 release of 2.0.0. What should I change to make this example compile and run?
The problem was never determined. The solution was to comment out all code in all other scala files in the project, recompile, then uncomment and compile again. No doubt an
sbt clean
would have done just as well.
What is the status of the continuations plugin in Scala 2.10; I'm slightly confused. The following setup is in the Akka 2.2-SNAPSHOT documentation:
autoCompilerPlugins := true,
libraryDependencies <+= scalaVersion {
v => compilerPlugin("org.scala-lang.plugins" % "continuations" % "2.10.0")
},
scalacOptions += "-P:continuations:enable",
First, the scalacOption doesn't work with 2.10 anymore, and the scalaVersion is not actually used in the library dependencies. If I naively go ahead with 2.10 and no special configurations (remove all of the above), and Akka 2.1.0:
import concurrent.ExecutionContext.Implicits.global
import akka.dataflow._
flow { "Hello world!" } onComplete println
I get an error indicating that the continuations plug-in is not enabled.
What what is the correct approach to enable continuations in Scala 2.10?
In particular: How can I drop into the sbt console and try out the above example with flow. It seems I also need to make sure the compiler plugin is enabled for the REPL?
EDIT: The scalacOptions entry does work, it seems I had a typo.
With this build.sbt:
autoCompilerPlugins := true
scalaVersion := "2.10.0"
libraryDependencies +=
compilerPlugin("org.scala-lang.plugins" % "continuations" % "2.10.0")
scalacOptions += "-P:continuations:enable"
the following continuations-only (no Akka) example works in the REPL:
scala> import scala.util.continuations._
scala> reset { val i = shift { body: (Int => Unit) => body(5);
| println("done") }; println(i) }