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// Bootstrap 5 tabs Scala.js + Outwatch wrapper

final class Tab(
  tabId: String,
  selected: Boolean,
  label: String,
  content: VDomModifier,
) {

  def navLi: HtmlVNode =

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import outwatch.helpers.AttributeBuilder
import outwatch.{Attr, HtmlVNode, VDomModifier}

import scala.language.implicitConversions

object TestComponent extends TestViews(outwatch.dsl) {

  type TModifier = VDomModifier
  type TRes = VDomModifier
  type AtPr = Attr

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// "фиксированная" структура
sealed trait BinTree
final case class BinNode(t1: BinTree, t2: BinTree) extends BinTree
final case class Leaf(v: Int) extends BinTree

// в фиксированном варианте возможно только создание простых деревьев,
// их структура заранее зафиксирована в определениях BinNode и Leaf
BinNode(Leaf(1),BinNode(Leaf(2),Leaf(3)))
// к примеру, невозможно создать дерево с необязательными элементами
// оно не скомпилируется

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package syntax

import cats.data.NonEmptyList
import cats.syntax.reducible._

package object catssyntax {
  
  object InitLastNel {
    def unapply[T](nel: NonEmptyList[T]): Option[(List[T], T)] =
      (nel.init, nel.last).some

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// based on https://michid.wordpress.com/2010/01/29/scala-type-level-encoding-of-the-ski-calculus/

trait Term {
  type ap[x <: Term] <: Term
  type eval <: Term
}
   
// The S combinator
trait S extends Term {
  type ap[x <: Term] = S1[x] 

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Анонимные функции в ООП

// Тип функции A -> B в Scala
trait Function[A, B] {
  def apply(p: A): B
}

// Функциональное значение в Scala

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-- since MSSQL 2008 use
-- ALTER USER OrphanUser WITH LOGIN = correctedLoginName;

DECLARE @uname varchar(30) 
DECLARE curs1 CURSOR FOR 
  SELECT name
    FROM sysusers
    WHERE name <> 'dbo' AND issqluser = 1 AND hasdbaccess = 1
    ORDER BY name
OPEN curs1 

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sealed trait Term

case class Var(name: String) extends Term
case class Lambda(param: Var, body: Term) extends Term
case class App(term1: Term, term2: Term) extends Term

object LambdaReduce {

  def substitute(term: Term, v: Var, body: Term): Term = body match {
    case Var(name) => ???

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Check and.
Check or.

Check True.
Check False.

Print True.
Print False.

Variable A: Prop.

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Definition compose {A: Type} (f g: A -> A) (x: A) := f (g x).

Lemma comp_eq: forall (A: Type) (f g: A -> A) (x: A), compose f g x = f (g x).
Proof.
intros.
unfold compose.
exact eq_refl.
Qed.