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-rw-r--r--examples/src/main/scala/decode.scala79
1 files changed, 0 insertions, 79 deletions
diff --git a/examples/src/main/scala/decode.scala b/examples/src/main/scala/decode.scala
deleted file mode 100644
index 5b083bd..0000000
--- a/examples/src/main/scala/decode.scala
+++ /dev/null
@@ -1,79 +0,0 @@
-package magnolia.examples
-
-import magnolia._
-import scala.language.experimental.macros
-
-/** very basic decoder for converting strings to other types */
-trait Decoder[T] { def decode(str: String): T }
-
-/** derivation object (and companion object) for [[Decoder]] instances */
-object Decoder {
-
- /** decodes strings */
- implicit val string: Decoder[String] = new Decoder[String] {
- def decode(str: String): String = str
- }
-
- /** decodes ints */
- implicit val int: Decoder[Int] = new Decoder[Int] { def decode(str: String): Int = str.toInt }
-
- /** binds the Magnolia macro to this derivation object */
- implicit def gen[T]: Decoder[T] = macro Magnolia.gen[T]
-
- /** type constructor for new instances of the typeclass */
- type Typeclass[T] = Decoder[T]
-
- /** defines how new [[Decoder]]s for case classes should be constructed */
- def combine[T](ctx: CaseClass[Decoder, T]): Decoder[T] = new Decoder[T] {
- def decode(value: String) = {
- val (name, values) = parse(value)
- ctx.construct { param =>
- param.typeclass.decode(values(param.label))
- }
- }
- }
-
- /** defines how to choose which subtype of the sealed trait to use for decoding */
- def dispatch[T](ctx: SealedTrait[Decoder, T]): Decoder[T] = new Decoder[T] {
- def decode(param: String) = {
- val (name, values) = parse(param)
- val subtype = ctx.subtypes.find(_.label == name).get
- subtype.typeclass.decode(param)
- }
- }
-
- /** very simple extractor for grabbing an entire parameter value, assuming matching parentheses */
- private def parse(value: String): (String, Map[String, String]) = {
- val end = value.indexOf('(')
- val name = value.substring(0, end)
-
- def parts(value: String,
- idx: Int = 0,
- depth: Int = 0,
- collected: List[String] = List("")): List[String] = {
- def plus(char: Char): List[String] = collected.head + char :: collected.tail
-
- if (idx == value.length) collected
- else
- value(idx) match {
- case '(' =>
- parts(value, idx + 1, depth + 1, plus('('))
- case ')' =>
- if (depth == 1) plus(')')
- else parts(value, idx + 1, depth - 1, plus(')'))
- case ',' =>
- if (depth == 0) parts(value, idx + 1, depth, "" :: collected)
- else parts(value, idx + 1, depth, plus(','))
- case char =>
- parts(value, idx + 1, depth, plus(char))
- }
- }
-
- def keyValue(str: String): (String, String) = {
- val List(label, value) = str.split("=", 2).to[List]
- (label, value)
- }
-
- (name, parts(value.substring(end + 1, value.length - 1)).map(keyValue).toMap)
- }
-}