New encoding of FromDigits that has better visibility

Author: mpilquist

core/shared/src/main/scala-0.22/scodec/bits/ByteVectorPlatform.scala

@@ -4,38 +4,38 @@ import scala.quoted._
 import scala.quoted.matching._
 import scala.util.FromDigits
 
-// TODO: as of 0.22, making this private[bits] results in errors like the following at call sites:
-// scala> val b: ByteVector = 0x00112233_44556677_8899aabb_ccddeeff_fedba098
-// trait ByteVectorPlatform cannot be accessed as a member of scodec.bits from module class rs$line$2$.
-trait ByteVectorPlatform { self: ByteVector.type =>
+private[bits] trait ByteVectorPlatform { self: ByteVector.type =>
+  given as FromDigits.WithRadix[ByteVector] = ByteVectorFromDigits.Instance
+}
+
+object ByteVectorFromDigits {
+
+  private def digitsToByteVector(digits: String, radix: Int): ByteVector =
+    if (radix == 16) ByteVector.fromValidHex(digits.tail)
+    else throw FromDigits.MalformedNumber(s"unsupported radix $radix")
 
-  class FromDigits extends FromDigits.WithRadix[ByteVector] {
+  private[bits] class Base extends FromDigits.WithRadix[ByteVector] {
     def fromDigits(digits: String, radix: Int): ByteVector =
       digitsToByteVector(digits, radix)
   }
 
-  given FromDigits {
+  private[bits] object Instance extends Base {
     override inline def fromDigits(digits: String): ByteVector =
       ${digitsToByteVectorMacro('digits, Expr(10))}
     override inline def fromDigits(digits: String, radix: Int): ByteVector =
       ${digitsToByteVectorMacro('digits, 'radix)}
   }
-}
-
-private[bits] def digitsToByteVector(digits: String, radix: Int): ByteVector =
-  if (radix == 16) ByteVector.fromValidHex(digits.tail)
-  else throw FromDigits.MalformedNumber(s"unsupported radix $radix")
-
 
-def digitsToByteVectorMacro(digits: Expr[String], radix: Expr[Int])(given qctx: QuoteContext): Expr[ByteVector] =
-  (digits, radix) match {
-    case (Const(ds), Const(r)) =>
-      if (r == 16) {
-        '{ByteVector.fromValidHex($digits.tail)}
-      } else {
-        qctx.error(s"unsupported radix $r", radix)
-        '{ByteVector.empty}
-      }
-    case other =>
-      '{digitsToByteVector($digits, $radix)}
-  }
+  private def digitsToByteVectorMacro(digits: Expr[String], radix: Expr[Int])(given qctx: QuoteContext): Expr[ByteVector] =
+    (digits, radix) match {
+      case (Const(ds), Const(r)) =>
+        if (r == 16) {
+          '{ByteVector.fromValidHex($digits.tail)}
+        } else {
+          qctx.error(s"unsupported radix $r", radix)
+          '{ByteVector.empty}
+        }
+      case other =>
+        '{digitsToByteVector($digits, $radix)}
+    }
+}