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milessabin / metals.log
Created July 14, 2023 11:36
2023.07.14 12:33:50 INFO Started: Metals version 0.11.12 in workspace '/home/miles/projects/gsp-graphql' for client Neovim 0.9.1.
Jul 14, 2023 12:33:50 PM org.flywaydb.core.internal.license.VersionPrinter printVersionOnly
INFO: Flyway Community Edition 9.16.3 by Redgate
Jul 14, 2023 12:33:50 PM org.flywaydb.core.internal.license.VersionPrinter printVersion
INFO: See release notes here: https://rd.gt/416ObMi
Jul 14, 2023 12:33:50 PM org.flywaydb.core.internal.license.VersionPrinter printVersion
INFO:
Jul 14, 2023 12:33:50 PM org.flywaydb.core.internal.database.base.BaseDatabaseType createDatabase
INFO: Database: jdbc:h2:file:/home/miles/projects/gsp-graphql/.metals/metals (H2 2.1)
Jul 14, 2023 12:33:50 PM org.flywaydb.core.internal.command.DbValidate validate
@milessabin
milessabin / gist:2a30603841aa82990b0be54b8ad44596
Created June 2, 2023 14:33
java.net.ConnectException: Connection refused
| => sat java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.checkConnect(Native Method)
at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.finishConnect(UnixAsynchronousSocketChannelImpl.java:252)
at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.finish(UnixAsynchronousSocketChannelImpl.java:198)
at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.onEvent(UnixAsynchronousSocketChannelImpl.java:213)
at java.base/sun.nio.ch.EPollPort$EventHandlerTask.run(EPollPort.java:306)
at java.base/sun.nio.ch.AsynchronousChannelGroupImpl$1.run(AsynchronousChannelGroupImpl.java:112)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)
@milessabin
milessabin / tuplegeneric.scala
Last active March 13, 2023 20:27
Convert (small enough) case classes to and from tuples using shapeless ...
import shapeless._
import ops.hlist.Tupler
trait TupleGeneric[C <: Product] extends Serializable {
type Repr <: Product
def to(t : C) : Repr
def from(r : Repr) : C
}
@milessabin
milessabin / gist:6451859
Created September 5, 2013 15:37
Using pattern matching to destructure shapeless records.
scala> import shapeless._, syntax.singleton._, record._
import shapeless._
import syntax.singleton._
import record._
scala> object ->> {
| def unapply[K, V](f: FieldType[K, V])(implicit k: Witness.Aux[K]) = Option((k.value, f: V))
| }
defined module $minus$greater$greater
@milessabin
milessabin / match-types.scala
Created June 9, 2021 11:13
miles@tarski:~% cs launch scala3-repl
scala> trait A
| trait B
| type M[X] = X match
| case A => Int
| case B => String
|
// defined trait A
// defined trait B
@milessabin
milessabin / gist:c3c9fbc57b1d913c2ee4
Last active December 2, 2020 11:37
Merging arbitrary case classes via shapeless ... (LabelledGeneric and record merge).
import shapeless._
object CaseClassMergeDemo extends App {
import mergeSyntax._
case class Foo(i: Int, s: String, b: Boolean)
case class Bar(b: Boolean, s: String)
val foo = Foo(23, "foo", true)
val bar = Bar(false, "bar")
@milessabin
milessabin / trait-instances.scala
Last active June 23, 2020 08:40
Constraining a trait type parameter via a super class type parameter constraint
import cats.{Applicative, Monad}
import cats.implicits._
abstract class Foo[+M[_[_]], F[_]](implicit val M: M[F])
trait Bar[F[_]] extends Foo[Applicative, F] { def bar = Applicative[F] }
trait Baz[F[_]] extends Foo[Monad, F] { def baz = Monad[F] }
class User[F[_]: Monad] extends Bar[F] with Baz[F]
object Test {
@milessabin
milessabin / trait-instances-2.scala
Last active June 23, 2020 08:39
Constraining trait type parameters via a super class type parameter constraint ... different instances along different paths
import cats.{Applicative, Monad}
import cats.implicits._
abstract class Foo[+M[_[_]], F[_]](implicit val M: M[F])
trait Bar[F[_]] extends Foo[Applicative, F] { def bar = Applicative[F] }
trait Baz[F[_]] extends Foo[Monad, F] { def baz = Monad[F] }
class User[F[_]: Monad] extends Bar[F] with Baz[F]
object Test {
@milessabin
milessabin / gist:de58f3ba7024d51dcc1a
Created September 19, 2011 16:44
No Nothings
def unexpected : Nothing = sys.error("Unexpected invocation")
// Encoding for "A is not a subtype of B"
trait <:!<[A, B]
// Uses ambiguity to rule out the cases we're trying to exclude
implicit def nsub[A, B] : A <:!< B = null
implicit def nsubAmbig1[A, B >: A] : A <:!< B = unexpected
implicit def nsubAmbig2[A, B >: A] : A <:!< B = unexpected
@milessabin
milessabin / gist:1705644
Created January 30, 2012 17:47
Access to companion object of Foo via implicit resolution
trait Companion[T] {
type C
def apply() : C
}
object Companion {
implicit def companion[T](implicit comp : Companion[T]) = comp()
}
object TestCompanion {