= slick add explicit return type for implicit conversion

slick/src/main/scala/slick/jdbc/JdbcProfile.scala

@@ -61,7 +61,7 @@ trait JdbcProfile extends SqlProfile with JdbcActionComponent
     implicit def jdbcActionExtensionMethods[E <: Effect, R, S <: NoStream](a: DBIOAction[R, S, E]): JdbcActionExtensionMethods[E, R, S] =
       new JdbcActionExtensionMethods[E, R, S](a)
 
-    implicit def actionBasedSQLInterpolation(s: StringContext) = new ActionBasedSQLInterpolation(s)
+    implicit def actionBasedSQLInterpolation(s: StringContext): ActionBasedSQLInterpolation = new ActionBasedSQLInterpolation(s)
   }
 
   val api: API = new API {}

slick/src/main/scala/slick/lifted/ExtensionMethods.scala

@@ -226,21 +226,21 @@ final class AnyOptionExtensionMethods[O <: Rep[_], P](val r: O) extends AnyVal {
 }
 
 trait ExtensionMethodConversions {
-  implicit def columnExtensionMethods[B1 : BaseTypedType](c: Rep[B1]) = new BaseColumnExtensionMethods[B1](c)
-  implicit def optionColumnExtensionMethods[B1 : BaseTypedType](c: Rep[Option[B1]]) = new OptionColumnExtensionMethods[B1](c)
-  implicit def numericColumnExtensionMethods[B1](c: Rep[B1])(implicit tm: BaseTypedType[B1] with NumericTypedType) = new BaseNumericColumnExtensionMethods[B1](c)
-  implicit def numericOptionColumnExtensionMethods[B1](c: Rep[Option[B1]])(implicit tm: BaseTypedType[B1] with NumericTypedType) = new OptionNumericColumnExtensionMethods[B1](c)
-  implicit def stringColumnExtensionMethods(c: Rep[String]) = new StringColumnExtensionMethods[String](c)
-  implicit def stringOptionColumnExtensionMethods(c: Rep[Option[String]]) = new StringColumnExtensionMethods[Option[String]](c)
-  implicit def booleanColumnExtensionMethods(c: Rep[Boolean]) = new BooleanColumnExtensionMethods[Boolean](c)
-  implicit def booleanOptionColumnExtensionMethods(c: Rep[Option[Boolean]]) = new BooleanColumnExtensionMethods[Option[Boolean]](c)
-
-  implicit def anyColumnExtensionMethods[B1 : BaseTypedType](c: Rep[B1]) = new AnyExtensionMethods(c.toNode)
-  implicit def anyOptionColumnExtensionMethods[B1 : BaseTypedType](c: Rep[Option[B1]]) = new AnyExtensionMethods(c.toNode)
-  implicit def anyValueExtensionMethods[B1 : BaseTypedType](v: B1) = new AnyExtensionMethods(LiteralNode(implicitly[TypedType[B1]], v))
-  implicit def anyOptionValueExtensionMethods[B1 : BaseTypedType](v: Option[B1]) = new AnyExtensionMethods(LiteralNode(implicitly[TypedType[Option[B1]]], v))
-  implicit def singleColumnQueryExtensionMethods[B1 : BaseTypedType, C[_]](q: Query[Rep[B1], _, C]) = new SingleColumnQueryExtensionMethods[B1, B1, C](q)
-  implicit def singleOptionColumnQueryExtensionMethods[B1 : BaseTypedType, C[_]](q: Query[Rep[Option[B1]], _, C]) = new SingleColumnQueryExtensionMethods[B1, Option[B1], C](q)
-
-  implicit def anyOptionExtensionMethods[T, P](v: Rep[Option[T]])(implicit ol: OptionLift[P, Rep[Option[T]]]) = new AnyOptionExtensionMethods[Rep[Option[T]], P](v)
+  implicit def columnExtensionMethods[B1 : BaseTypedType](c: Rep[B1]): BaseColumnExtensionMethods[B1] = new BaseColumnExtensionMethods[B1](c)
+  implicit def optionColumnExtensionMethods[B1 : BaseTypedType](c: Rep[Option[B1]]): OptionColumnExtensionMethods[B1] = new OptionColumnExtensionMethods[B1](c)
+  implicit def numericColumnExtensionMethods[B1](c: Rep[B1])(implicit tm: BaseTypedType[B1] with NumericTypedType): BaseNumericColumnExtensionMethods[B1] = new BaseNumericColumnExtensionMethods[B1](c)
+  implicit def numericOptionColumnExtensionMethods[B1](c: Rep[Option[B1]])(implicit tm: BaseTypedType[B1] with NumericTypedType): OptionNumericColumnExtensionMethods[B1] = new OptionNumericColumnExtensionMethods[B1](c)
+  implicit def stringColumnExtensionMethods(c: Rep[String]): StringColumnExtensionMethods[String] = new StringColumnExtensionMethods[String](c)
+  implicit def stringOptionColumnExtensionMethods(c: Rep[Option[String]]): StringColumnExtensionMethods[Option[String]] = new StringColumnExtensionMethods[Option[String]](c)
+  implicit def booleanColumnExtensionMethods(c: Rep[Boolean]): BooleanColumnExtensionMethods[Boolean] = new BooleanColumnExtensionMethods[Boolean](c)
+  implicit def booleanOptionColumnExtensionMethods(c: Rep[Option[Boolean]]): BooleanColumnExtensionMethods[Option[Boolean]] = new BooleanColumnExtensionMethods[Option[Boolean]](c)
+
+  implicit def anyColumnExtensionMethods[B1 : BaseTypedType](c: Rep[B1]): AnyExtensionMethods = new AnyExtensionMethods(c.toNode)
+  implicit def anyOptionColumnExtensionMethods[B1 : BaseTypedType](c: Rep[Option[B1]]): AnyExtensionMethods = new AnyExtensionMethods(c.toNode)
+  implicit def anyValueExtensionMethods[B1 : BaseTypedType](v: B1): AnyExtensionMethods = new AnyExtensionMethods(LiteralNode(implicitly[TypedType[B1]], v))
+  implicit def anyOptionValueExtensionMethods[B1 : BaseTypedType](v: Option[B1]): AnyExtensionMethods = new AnyExtensionMethods(LiteralNode(implicitly[TypedType[Option[B1]]], v))
+  implicit def singleColumnQueryExtensionMethods[B1 : BaseTypedType, C[_]](q: Query[Rep[B1], _, C]): SingleColumnQueryExtensionMethods[B1, B1, C] = new SingleColumnQueryExtensionMethods[B1, B1, C](q)
+  implicit def singleOptionColumnQueryExtensionMethods[B1 : BaseTypedType, C[_]](q: Query[Rep[Option[B1]], _, C]): SingleColumnQueryExtensionMethods[B1, Option[B1], C] = new SingleColumnQueryExtensionMethods[B1, Option[B1], C](q)
+
+  implicit def anyOptionExtensionMethods[T, P](v: Rep[Option[T]])(implicit ol: OptionLift[P, Rep[Option[T]]]): AnyOptionExtensionMethods[Rep[Option[T]], P] = new AnyOptionExtensionMethods[Rep[Option[T]], P](v)
 }

slick/src/main/scala/slick/lifted/FunctionSymbolExtensionMethods.scala

@@ -10,5 +10,5 @@ final class FunctionSymbolExtensionMethods(val fs: FunctionSymbol) /*extends Any
 }
 
 object FunctionSymbolExtensionMethods {
-  implicit def functionSymbolExtensionMethods(fs: FunctionSymbol) = new FunctionSymbolExtensionMethods(fs)
+  implicit def functionSymbolExtensionMethods(fs: FunctionSymbol): FunctionSymbolExtensionMethods = new FunctionSymbolExtensionMethods(fs)
 }

slick/src/main/scala/slick/relational/RelationalProfile.scala

@@ -1,16 +1,14 @@
 package slick.relational
 
-import scala.language.{implicitConversions, higherKinds, existentials}
-import scala.reflect.ClassTag
-
-import slick.SlickException
 import slick.ast._
 import slick.basic.{BasicActionComponent, BasicProfile}
-import slick.compiler.{Phase, EmulateOuterJoins, QueryCompiler}
+import slick.compiler.{EmulateOuterJoins, Phase, QueryCompiler}
 import slick.dbio._
-import slick.lifted._
 import slick.lifted.FunctionSymbolExtensionMethods._
-import slick.util.{TupleMethods, TupleSupport}
+import slick.lifted._
+
+import scala.language.{existentials, higherKinds, implicitConversions}
+import scala.reflect.ClassTag
 
 /** A profile for relational databases that does not assume the existence
   * of SQL (or any other text-based language for executing statements).
@@ -37,13 +35,13 @@ trait RelationalProfile extends BasicProfile with RelationalTableComponent
 
     @deprecated("Use an explicit conversion to an Option column with `.?`", "3.0")
     implicit def columnToOptionColumn[T : BaseTypedType](c: Rep[T]): Rep[Option[T]] = c.?
-    implicit def valueToConstColumn[T : TypedType](v: T) = new LiteralColumn[T](v)
+    implicit def valueToConstColumn[T : TypedType](v: T): LiteralColumn[T] = new LiteralColumn[T](v)
     implicit def columnToOrdered[T : TypedType](c: Rep[T]): ColumnOrdered[T] = ColumnOrdered[T](c, Ordering())
-    implicit def tableQueryToTableQueryExtensionMethods[T <: RelationalProfile#Table[_], U](q: Query[T, U, Seq] with TableQuery[T]) =
+    implicit def tableQueryToTableQueryExtensionMethods[T <: RelationalProfile#Table[_], U](q: Query[T, U, Seq] with TableQuery[T]): TableQueryExtensionMethods[T, U] =
       new TableQueryExtensionMethods[T, U](q)
 
     implicit def streamableCompiledInsertActionExtensionMethods[EU](c: StreamableCompiled[_, _, EU]): InsertActionExtensionMethods[EU] = createInsertActionExtensionMethods[EU](c.compiledInsert.asInstanceOf[CompiledInsert])
-    implicit def queryInsertActionExtensionMethods[U, C[_]](q: Query[_, U, C]) = createInsertActionExtensionMethods[U](compileInsert(q.toNode))
+    implicit def queryInsertActionExtensionMethods[U, C[_]](q: Query[_, U, C]): InsertActionExtensionMethods[U] = createInsertActionExtensionMethods[U](compileInsert(q.toNode))
 
     implicit def schemaActionExtensionMethods(sd: SchemaDescription): SchemaActionExtensionMethods = createSchemaActionExtensionMethods(sd)
 

slick/src/main/scala/slick/util/MacroSupport.scala

@@ -4,7 +4,7 @@ import scala.language.experimental.macros
 import scala.language.implicitConversions
 
 object MacroSupport {
-  implicit def macroSupportInterpolation(s: StringContext) = new MacroSupportInterpolation(s)
+  implicit def macroSupportInterpolation(s: StringContext): MacroSupportInterpolation = new MacroSupportInterpolation(s)
 }
 
 class MacroSupportInterpolation(context: StringContext) {