Addresses the issues swirling around Double.Eps...

Addresses the issues swirling around Double.Epsilon and friends which
were battled out in more than one venue and then aptly summarized by
retronym in #3791. Thanks to Simon Ochsenreither for submitting a patch;
I wasn't able to use too much of it because the source code for these
types is generated, but effort is always appreciated. Closes #3791, and
I'm tired and I'd hate to blow this one at this late date: review by
rytz.

14 files changed, 94 insertions, 66 deletions

diff --git a/src/compiler/scala/tools/cmd/gen/AnyVals.scala b/src/compiler/scala/tools/cmd/gen/AnyVals.scala
index 23a31a56b4..f6f48359cd 100644
--- a/src/compiler/scala/tools/cmd/gen/AnyVals.scala
+++ b/src/compiler/scala/tools/cmd/gen/AnyVals.scala
@@ -7,9 +7,8 @@ package scala.tools.cmd
 package gen
 
 trait AnyValTemplates {
-  def timestampString = "// generated on " + new java.util.Date + "\n"
-
-  def template = """
+  def timestampString = ""
+  def template = ("""
 /*                     __                                               *\
 **     ________ ___   / /  ___     Scala API                            **
 **    / __/ __// _ | / /  / _ |    (c) 2002-2011, LAMP/EPFL             **
@@ -22,10 +21,10 @@ trait AnyValTemplates {
 package scala
 
 import java.{ lang => jl }
-
   """.trim.format(timestampString) + "\n\n"
+  )
 
-  val booleanBody = """
+  def booleanBody = """
 final class Boolean extends AnyVal {
   def unary_! : Boolean = sys.error("stub")
 
@@ -48,7 +47,7 @@ object Boolean extends AnyValCompanion {
 }
   """.trim
 
-  val unitBody = """
+  def unitBody = """
 import runtime.BoxedUnit
 
 final class Unit extends AnyVal { }
@@ -59,6 +58,40 @@ object Unit extends AnyValCompanion {
   def unbox(x: jl.Object): Unit = ()
 }
   """.trim
+
+  def cardinalCompanion = """
+final val MinValue = @type@.MIN_VALUE
+final val MaxValue = @type@.MAX_VALUE
+
+def box(x: @name@): @type@ = @type@.valueOf(x)
+def unbox(x: jl.Object): @name@ = x.asInstanceOf[@type@].@lcname@Value()
+override def toString = "object scala.@name@"
+  """.trim.lines
+
+  def floatingCompanion = """
+/** The smallest positive value greater than @zero@.*/
+final val MinPositiveValue = @type@.MIN_VALUE
+final val NaN              = @type@.NaN
+final val PositiveInfinity = @type@.POSITIVE_INFINITY
+final val NegativeInfinity = @type@.NEGATIVE_INFINITY
+
+@deprecated("use @name@.MinPositiveValue instead")
+final val Epsilon  = MinPositiveValue
+
+/** The negative number with the greatest (finite) absolute value which is representable
+ *  by a @name@.  Note that it differs from [[java.lang.@name@.MIN_VALUE]], which
+ *  is the smallest positive value representable by a @name@.  In Scala that number
+ *  is called @name@.MinPositiveValue.
+ */
+final val MinValue = -@type@.MAX_VALUE
+
+/** The largest finite positive number representable as a @name@. */
+final val MaxValue = @type@.MAX_VALUE
+
+def box(x: @name@): @type@ = @type@.valueOf(x)
+def unbox(x: jl.Object): @name@ = x.asInstanceOf[@type@].@lcname@Value()
+override def toString = "object scala.@name@"
+  """.trim.lines
 }
 
 class AnyVals extends AnyValTemplates {
@@ -90,11 +123,18 @@ class AnyVals extends AnyValTemplates {
     val isCardinal = cardinal contains name
     val restype    = if ("LFD" contains name.head) name else I
     val tpe        = javaType(name)
+    val zero       = name.head match {
+      case 'L' => "0L"
+      case 'F' => "0.0f"
+      case 'D' => "0.0d"
+      case _   => "0"
+    }
     val interpolations = Map(
       "@restype@"  -> restype,
       "@name@"     -> name,
       "@type@"     -> tpe,
-      "@lcname@"   -> name.toLowerCase
+      "@lcname@"   -> name.toLowerCase,
+      "@zero@"     -> zero
     )
 
     def mkCoercions = numeric map (x => "def to%s: %s".format(x, x))
@@ -131,7 +171,7 @@ class AnyVals extends AnyValTemplates {
       }
       assemble("final class", "AnyVal", lines)
     }
-    def mkObject = assemble("object", "AnyValCompanion", companionLines map interpolate)
+    def mkObject = assemble("object", "AnyValCompanion", companionBody map interpolate toList)
 
     def assemble(what: String, parent: String, lines: List[String]): String = (
       List(what, name, "extends", parent, "{").mkString(" ") +:
@@ -171,35 +211,9 @@ class AnyVals extends AnyValTemplates {
     def boolBinops  = List("==", "!=", "<", "<=", ">", ">=")
     def otherBinops = List("+", "-" ,"*", "/", "%")
 
-    def floatingCompanion = List(
-      "final val MinPositiveValue = @type@.MIN_VALUE",
-      "final val MinNegativeValue = -@type@.MAX_VALUE",
-      "final val NaN              = @type@.NaN",
-      "final val PositiveInfinity = @type@.POSITIVE_INFINITY",
-      "final val NegativeInfinity = @type@.NEGATIVE_INFINITY",
-      "",
-      """@deprecated("use @name@.MinPositiveValue instead")""",
-      "final val Epsilon          = MinPositiveValue",
-      """@deprecated("use @name@.MinNegativeValue instead")""",
-      "final val MinValue = MinNegativeValue"
-    )
-
-    def cardinalCompanion = List(
-      "final val MinValue = @type@.MIN_VALUE"
-    )
-
-    def commonCompanion = List(
-      "final val MaxValue = @type@.MAX_VALUE",
-      "",
-      "def box(x: @name@): @type@ = @type@.valueOf(x)",
-      "def unbox(x: jl.Object): @name@ = x.asInstanceOf[@type@].@lcname@Value()",
-      "override def toString = \"object scala.@name@\""
-    )
-
-    def companionLines = (
+    def companionBody =
       if (isCardinal) cardinalCompanion
       else floatingCompanion
-    ) ++ commonCompanion
   }
 }
 
diff --git a/src/compiler/scala/tools/cmd/gen/Codegen.scala b/src/compiler/scala/tools/cmd/gen/Codegen.scala
index a96e53d4e2..d7801f2c08 100644
--- a/src/compiler/scala/tools/cmd/gen/Codegen.scala
+++ b/src/compiler/scala/tools/cmd/gen/Codegen.scala
@@ -27,19 +27,19 @@ object Codegen {
 
     if (anyvals || all) {
       val av = new AnyVals {
-        override def timestampString =
-          if (stamp) super.timestampString
-          else ""
+        override def timestampString = (
+          "// DO NOT EDIT, CHANGES WILL BE LOST.\n" + (
+            if (stamp) "// Generated by tools/codegen on " + new java.util.Date + "\n" else ""
+          )
+        )
       }
+
       av.make() foreach { case (name, code ) =>
         val file = out / (name + ".scala") toFile;
         echo("Writing: " + file)
         file writeAll code
       }
     }
-    if (products || all) {
-      ()
-    }
   }
 }
 
diff --git a/src/compiler/scala/tools/cmd/gen/CodegenSpec.scala b/src/compiler/scala/tools/cmd/gen/CodegenSpec.scala
index e99c49721f..7f4b9c1bb0 100644
--- a/src/compiler/scala/tools/cmd/gen/CodegenSpec.scala
+++ b/src/compiler/scala/tools/cmd/gen/CodegenSpec.scala
@@ -10,15 +10,15 @@ import FromString.ExistingDir
 
 trait CodegenSpec extends Spec with Meta.StdOpts with Interpolation {
   def referenceSpec       = CodegenSpec
-  def programInfo         = Spec.Info("codegen", "", "scala.tools.cmd.cmd")
+  def programInfo         = Spec.Info("codegen", "", "scala.tools.cmd.gen.Codegen")
 
   import FromString.ExistingDir
 
   help("Usage: codegen [<options>]")
 
-  val inDir    = "in" / "directory containing templates" --^ ExistingDir
+  // val inDir    = "in" / "directory containing templates" --^ ExistingDir
   val outDir   = "out" / "directory for generated files" --^ ExistingDir
-  val install  = "install" / "write source files directly to src/library/scala"
+  // val install  = "install" / "write source files directly to src/library/scala"
   val anyvals  = "anyvals" / "generate sources for AnyVal types" --?
   val products = "products" / "generate sources for ProductN, FunctionN, etc." --?
   val genall   = "all" / "generate sources for everything" --?
diff --git a/src/library/scala/Boolean.scala b/src/library/scala/Boolean.scala
index d5e9eb950e..dc2076cb1d 100755
--- a/src/library/scala/Boolean.scala
+++ b/src/library/scala/Boolean.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Byte.scala b/src/library/scala/Byte.scala
index e3f4a82003..69d435b33b 100644
--- a/src/library/scala/Byte.scala
+++ b/src/library/scala/Byte.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Char.scala b/src/library/scala/Char.scala
index 3c3f292fd2..88d7617ea5 100644
--- a/src/library/scala/Char.scala
+++ b/src/library/scala/Char.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Double.scala b/src/library/scala/Double.scala
index cc4f597bda..fe37860c07 100644
--- a/src/library/scala/Double.scala
+++ b/src/library/scala/Double.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
@@ -119,16 +119,23 @@ final class Double extends AnyVal {
 
 
 object Double extends AnyValCompanion {
+  /** The smallest positive value greater than 0.0d.*/
   final val MinPositiveValue = jl.Double.MIN_VALUE
-  final val MinNegativeValue = -jl.Double.MAX_VALUE
   final val NaN              = jl.Double.NaN
   final val PositiveInfinity = jl.Double.POSITIVE_INFINITY
   final val NegativeInfinity = jl.Double.NEGATIVE_INFINITY
 
   @deprecated("use Double.MinPositiveValue instead")
-  final val Epsilon          = MinPositiveValue
-  @deprecated("use Double.MinNegativeValue instead")
-  final val MinValue = MinNegativeValue
+  final val Epsilon  = MinPositiveValue
+
+  /** The negative number with the greatest (finite) absolute value which is representable
+   *  by a Double.  Note that it differs from [[java.lang.Double.MIN_VALUE]], which
+   *  is the smallest positive value representable by a Double.  In Scala that number
+   *  is called Double.MinPositiveValue.
+   */
+  final val MinValue = -jl.Double.MAX_VALUE
+
+  /** The largest finite positive number representable as a Double. */
   final val MaxValue = jl.Double.MAX_VALUE
 
   def box(x: Double): jl.Double = jl.Double.valueOf(x)
diff --git a/src/library/scala/Float.scala b/src/library/scala/Float.scala
index 81b464078d..39e510e477 100644
--- a/src/library/scala/Float.scala
+++ b/src/library/scala/Float.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
@@ -119,16 +119,23 @@ final class Float extends AnyVal {
 
 
 object Float extends AnyValCompanion {
+  /** The smallest positive value greater than 0.0f.*/
   final val MinPositiveValue = jl.Float.MIN_VALUE
-  final val MinNegativeValue = -jl.Float.MAX_VALUE
   final val NaN              = jl.Float.NaN
   final val PositiveInfinity = jl.Float.POSITIVE_INFINITY
   final val NegativeInfinity = jl.Float.NEGATIVE_INFINITY
 
   @deprecated("use Float.MinPositiveValue instead")
-  final val Epsilon          = MinPositiveValue
-  @deprecated("use Float.MinNegativeValue instead")
-  final val MinValue = MinNegativeValue
+  final val Epsilon  = MinPositiveValue
+
+  /** The negative number with the greatest (finite) absolute value which is representable
+   *  by a Float.  Note that it differs from [[java.lang.Float.MIN_VALUE]], which
+   *  is the smallest positive value representable by a Float.  In Scala that number
+   *  is called Float.MinPositiveValue.
+   */
+  final val MinValue = -jl.Float.MAX_VALUE
+
+  /** The largest finite positive number representable as a Float. */
   final val MaxValue = jl.Float.MAX_VALUE
 
   def box(x: Float): jl.Float = jl.Float.valueOf(x)
diff --git a/src/library/scala/Int.scala b/src/library/scala/Int.scala
index 416512d43b..69fb0a66b7 100644
--- a/src/library/scala/Int.scala
+++ b/src/library/scala/Int.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Long.scala b/src/library/scala/Long.scala
index 25b6873e72..7fdefebae3 100644
--- a/src/library/scala/Long.scala
+++ b/src/library/scala/Long.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Math.scala b/src/library/scala/Math.scala
index 3d300b8259..a1663a6a02 100644
--- a/src/library/scala/Math.scala
+++ b/src/library/scala/Math.scala
@@ -13,7 +13,7 @@ package scala
  *  operations such as the elementary exponential, logarithm, square root, and
  *  trigonometric functions.
  */
-@deprecated("use scala.math package object instead.\n(Example package object usage: scala.math.Pi )")
+@deprecated("use the scala.math package object instead.\n(Example package object usage: scala.math.Pi )")
 object Math extends MathCommon {
   @deprecated("Use scala.Byte.MinValue instead")
   val MIN_BYTE = java.lang.Byte.MIN_VALUE
@@ -50,7 +50,7 @@ object Math extends MathCommon {
   val MIN_FLOAT  = -java.lang.Float.MAX_VALUE
 
   /** The smallest difference between two values of <a href="Float.html" target="_self">scala.Float</a>. */
-  @deprecated("Use scala.Float.Epsilon instead")
+  @deprecated("Use scala.Float.MinPositiveValue instead")
   val EPS_FLOAT  = java.lang.Float.MIN_VALUE
 
   /** The greatest possible value for <a href="Float.html" target="_self">scala.Float</a>. */
@@ -74,7 +74,7 @@ object Math extends MathCommon {
   val MIN_DOUBLE = -java.lang.Double.MAX_VALUE
 
   /** The smallest difference between two values of <a href="Double.html" target="_self">scala.Double</a>. */
-  @deprecated("Use scala.Double.Epsilon instead")
+  @deprecated("Use scala.Double.MinPositiveValue instead")
   val EPS_DOUBLE = java.lang.Double.MIN_VALUE
 
   /** The greatest possible value for <a href="Double.html" target="_self">scala.Double</a>. */
diff --git a/src/library/scala/Short.scala b/src/library/scala/Short.scala
index abbb939c4c..df3e680575 100644
--- a/src/library/scala/Short.scala
+++ b/src/library/scala/Short.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/library/scala/Unit.scala b/src/library/scala/Unit.scala
index 7ef282a9ad..9e2d4dc616 100755
--- a/src/library/scala/Unit.scala
+++ b/src/library/scala/Unit.scala
@@ -6,7 +6,7 @@
 **                          |/                                          **
 \*                                                                      */
 
-// generated on Sun Jan 23 21:13:38 PST 2011
+// DO NOT EDIT, CHANGES WILL BE LOST.
 
 package scala
 
diff --git a/src/scalacheck/org/scalacheck/Arbitrary.scala b/src/scalacheck/org/scalacheck/Arbitrary.scala
index 388c3dccff..14d2b9b924 100644
--- a/src/scalacheck/org/scalacheck/Arbitrary.scala
+++ b/src/scalacheck/org/scalacheck/Arbitrary.scala
@@ -98,7 +98,7 @@ object Arbitrary {
   /** Arbitrary instance of Float */
   implicit lazy val arbFloat: Arbitrary[Float] = Arbitrary(
     Gen.chooseNum(
-      Float.MinNegativeValue, Float.MaxValue
+      Float.MinValue, Float.MaxValue
       // I find that including these by default is a little TOO testy.
       // Float.Epsilon, Float.NaN, Float.PositiveInfinity, Float.NegativeInfinity
     )
@@ -107,7 +107,7 @@ object Arbitrary {
   /** Arbitrary instance of Double */
   implicit lazy val arbDouble: Arbitrary[Double] = Arbitrary(
     Gen.chooseNum(
-      Double.MinNegativeValue / 2, Double.MaxValue / 2
+      Double.MinValue / 2, Double.MaxValue / 2
       // As above.  Perhaps behind some option?
       // Double.Epsilon, Double.NaN, Double.PositiveInfinity, Double.NegativeInfinity
     )