Add Forall instance for proper collections

build.sbt

@@ -46,7 +46,6 @@ initialCommands := """
   import eu.timepit.refined.char._
   import eu.timepit.refined.collection._
   import eu.timepit.refined.numeric._
-  import eu.timepit.refined.string._
   import shapeless.nat._
   import shapeless.tag.@@
 """
@@ -75,5 +74,5 @@ pomExtra :=
 
 site.settings
 site.includeScaladoc()
-ghpages.settings
+//ghpages.settings
 git.remoteRepo := "git@github.com:fthomas/refined.git"

project/plugin-ghpages.sbt

@@ -1,3 +1,3 @@
-resolvers += "jgit-repo" at "http://download.eclipse.org/jgit/maven"
+//resolvers += "jgit-repo" at "http://download.eclipse.org/jgit/maven"
 
-addSbtPlugin("com.typesafe.sbt" % "sbt-ghpages" % "0.5.3")
+//addSbtPlugin("com.typesafe.sbt" % "sbt-ghpages" % "0.5.3")

src/main/scala/eu/timepit/refined/collection.scala

@@ -19,7 +19,13 @@ object collection {
       def show(t: T): String = s"isEmpty($t)"
     }
 
-  implicit def forallPredicate[P, T, A](implicit p: Predicate[P, A], ev: T => TraversableOnce[A]): Predicate[Forall[P], T] =
+  implicit def forallPredicate[P, A, T[A] <: TraversableOnce[A]](implicit p: Predicate[P, A]): Predicate[Forall[P], T[A]] =
+    new Predicate[Forall[P], T[A]] {
+      def isValid(t: T[A]): Boolean = t.forall(p.isValid)
+      def show(t: T[A]): String = t.toSeq.map(p.show).mkString("(", " && ", ")")
+    }
+
+  implicit def forallPredicateView[P, A, T](implicit p: Predicate[P, A], ev: T => TraversableOnce[A]): Predicate[Forall[P], T] =
     new Predicate[Forall[P], T] {
       def isValid(t: T): Boolean = t.forall(p.isValid)
       def show(t: T): String = t.toSeq.map(p.show).mkString("(", " && ", ")")

src/test/scala/eu/timepit/refined/CollectionSpec.scala

@@ -0,0 +1,13 @@
+package eu.timepit.refined
+
+import eu.timepit.refined.collection._
+import eu.timepit.refined.numeric._
+import org.scalacheck.Prop._
+import org.scalacheck.Properties
+import shapeless.nat._
+
+class CollectionSpec extends Properties("collection") {
+  property("Exists[Equal[_]]") = forAll { (l: List[Int]) =>
+    Predicate[Exists[Equal[_1]], List[Int]].isValid(l) == l.contains(1)
+  }
+}