It seems like in Play framework templates,
there is an implicit "@import models._" and "@import play.api.data.Form" because my code:
@(title: String)(myForm: Form[User])
<!DOCTYPE html>
<html>
....
</html>
works without having to put explicit import statements after the first line. This issue has been raised in the past: https://groups.google.com/d/msg/play-framework/7FT68jd5asU/xYF0VNySJYcJ
What other classes/objects are implicitly imported?
You're right, Play Framework automatically add some import statements to all templates.
You can find these "default imports" in the PlaySettings trait from Play source code : https://github.com/playframework/Play20/blob/2.1.x/framework/src/sbt-plugin/src/main/scala/PlaySettings.scala
If you need to, you can add some additional imports in the project settings defined in your Build.scala :
val main = PlayProject(appName, appVersion, appDependencies, mainLang = JAVA).settings(
templatesImport += "com.acme._"
)
As of Play 2.3 I use this line in build.sbt
TwirlKeys.templateImports ++= Seq("very.long.package._", "another.package._")
You can look up the file : https://github.com/playframework/playframework/blob/master/framework/src/sbt-plugin/src/main/scala/PlayImport.scala#L40
All those mentioned there are imported.
Additionally, templatesImport += "com.acme._" is enough in 2.2.X to import all the files from a package i.e. in the file build.sbt.
来源：https://stackoverflow.com/questions/17397215/play-framework-template-automatically-imports-models-among-other-things