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Shapeless.md

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Shapeless module

First import the Shapeless environment and create the data model.

package net.scalax.ohNoMyCirce.test

import shapeless._
import scala.language.existentials //To avoid warnings

object TestShapeless {

  case class Model(id: Long, name: String, age: Int, describe: Int, time: Int)

  //The code will be written here later

}

Then insert the code to the place of the comment.

val model = 36444L :: "sdfsfsd" :: 343 :: {
  def testStr = "I am test string."
  val bb = testStr
  val cc = bb.size
  cc.toLong
} :: HNil
Generic[Model].from(model)

Oh, no!

[error] TestShapeless.scala:16:23: type mismatch;
[error]  found   : Long :: String :: Int :: Long :: shapeless.HNil
[error]  required: Long :: String :: Int :: Int :: Int :: shapeless.HNil
[error]   Generic[Model].from(model)
[error]                       ^
[error] one error found

And then start debugging.

val model = 36444L :: "sdfsfsd" :: 343 :: {
  def testStr = "I am test string."
  val bb = testStr
  val cc = bb.size
  cc.toLong
} :: HNil
ohNoMyCirce.shapelessFrom[Model](model) //Added
Generic[Model].from(model)

Error messages:

[error] TestShapeless.scala:16:35: Generic error:
[error] Case Class Type  : net.scalax.ohNoMyCirce.test.TestShapeless.Model
[error] Except HList size: 5
[error] Current size     : 4
[error]   ohNoMyCirce.shapelessFrom[Model](model) //Added
[error]                                   ^
[error] TestShapeless.scala:17:23: type mismatch;
[error]  found   : Long :: String :: Int :: Long :: shapeless.HNil
[error]  required: Long :: String :: Int :: Int :: Int :: shapeless.HNil
[error]   Generic[Model].from(model)
[error]                       ^
[error] two errors found

Next, add an element to the end of the HList:

val model = 36444L :: "sdfsfsd" :: 343 :: {
  def testStr = "I am test string."
  val bb = testStr
  val cc = bb.size
  cc.toLong
} :: 486 :: HNil
ohNoMyCirce.shapelessFrom[Model](model)
Generic[Model].from(model)

Error messages:

[error] TestShapeless.scala:16:35: Generic error:
[error] Case Class Type            :
[error] net.scalax.ohNoMyCirce.test.TestShapeless.Model
[error] HList size                 : 5
[error] Element index(0 base)      : 3
[error] Expect Property Type       : Int
[error] Property Name              : describe
[error] Not Confirm HList Item Type: Long
[error] Code Snippet               :
[error] No confirm code snippet
[error] Error occurred in an application involving default arguments.
[error]   ohNoMyCirce.shapelessFrom[Model](model)
[error]                                   ^
[error] TestShapeless.scala:17:23: type mismatch;
[error]  found   : Long :: String :: Int :: Long :: Int :: shapeless.HNil
[error]  required: Long :: String :: Int :: Int :: Int :: shapeless.HNil
[error]   Generic[Model].from(model)
[error]                       ^
[error] two errors found

Emmm, this error message has been very detailed, but I can not quickly determine if the wrong location is 343 or 486 or the block.

Add marks of these code snippets.

val model = 36444L :: "sdfsfsd" :: ohNoMyCirce.shapelessSnippet(343) :: ohNoMyCirce.shapelessSnippet {
  def testStr = "I am test string."
  val bb = testStr
  val cc = bb.size
  cc.toLong
} :: ohNoMyCirce.shapelessSnippet(486) :: HNil
ohNoMyCirce.shapelessFrom[Model](model)
Generic[Model].from(model)

Error messages:

[error] TestShapeless.scala:16:35: Generic error:
[error] Case Class Type            :
[error] net.scalax.ohNoMyCirce.test.TestShapeless.Model
[error] HList size                 : 5
[error] Element index(0 base)      : 3
[error] Expect Property Type       : Int
[error] Property Name              : describe
[error] Not Confirm HList Item Type: Long
[error] Code Snippet               :
[error] {
[error]   def testStr: String = "I am test string.";
[error]   val bb: String = testStr;
[error]   val cc: Int = scala.Predef.augmentString(bb).size;
[error]   cc.toLong
[error] }
[error]   ohNoMyCirce.shapelessFrom[Model](model)
[error]                                   ^
[error] TestShapeless.scala:17:23: type mismatch;
[error]  found   : Long :: String :: Int with net.scalax.ohNoMyShapeless.macros.
OhNoMyShapelessMacros.tag.OhNoTagged[Int,343] :: Long with net.scalax.ohNoMyShap
eless.macros.OhNoMyShapelessMacros.tag.OhNoTagged[Long,{
[error]   def testStr: String = "I am test string.";
[error]   val bb: String = testStr;
[error]   val cc: Int = scala.Predef.augmentString(bb).size;
[error]   cc.toLong
[error] }] :: Int with net.scalax.ohNoMyShapeless.macros.OhNoMyShapelessMacros.t
ag.OhNoTagged[Int,486] :: shapeless.HNil where type 486 <: AnyRef, type {
[error]   def testStr: String = "I am test string.";
[error]   val bb: String = testStr;
[error]   val cc: Int = scala.Predef.augmentString(bb).size;
[error]   cc.toLong
[error] } <: AnyRef, type 343 <: AnyRef
[error]  required: Long :: String :: Int :: Int :: Int :: shapeless.HNil
[error]   Generic[Model].from(model)
[error]                       ^
[error] two errors found

Don't pay attention to the second error message. Then you can find the error code snippet in the Code Snippet message.
Fix it:

val model = 36444L :: "sdfsfsd" :: ohNoMyCirce.shapelessSnippet(343) :: ohNoMyCirce.shapelessSnippet {
  def testStr = "I am test string."
  val bb = testStr
  val cc = bb.size
  cc.toLong.toInt
} :: ohNoMyCirce.shapelessSnippet(486) :: HNil
ohNoMyCirce.shapelessFrom[Model](model)
Generic[Model].from(model)

Oh, yes.

[info] Done compiling.

Remove the test code that has just been added.
Have fun!

The final version of the code above is here.