/* Title: Pure/term.scala
Author: Makarius
Lambda terms, types, sorts.
Note: Isabelle/ML is the primary environment for logical operations.
*/
package isabelle
object Term
{
/* types and terms */
sealed case class Indexname(name: String, index: Int = 0)
{
override def toString: String =
if (index == -1) name
else {
val dot =
Symbol.explode(name).reverse match {
case _ :: s :: _ if s == Symbol.sub_decoded || s == Symbol.sub => false
case c :: _ => Symbol.is_digit(c)
case _ => true
}
if (dot) "?" + name + "." + index
else if (index != 0) "?" + name + index
else "?" + name
}
}
type Class = String
type Sort = List[Class]
sealed abstract class Typ
case class Type(name: String, args: List[Typ] = Nil) extends Typ
{
override def toString: String =
if (this == dummyT) "_"
else "Type(" + name + (if (args.isEmpty) "" else "," + args) + ")"
}
case class TFree(name: String, sort: Sort = Nil) extends Typ
{
override def toString: String =
"TFree(" + name + (if (sort.isEmpty) "" else "," + sort) + ")"
}
case class TVar(name: Indexname, sort: Sort = Nil) extends Typ
{
override def toString: String =
"TVar(" + name + (if (sort.isEmpty) "" else "," + sort) + ")"
}
val dummyT: Type = Type("dummy")
sealed abstract class Term
{
def head: Term =
this match {
case App(fun, _) => fun.head
case _ => this
}
}
case class Const(name: String, typargs: List[Typ] = Nil) extends Term
{
override def toString: String =
if (this == dummy) "_"
else "Const(" + name + (if (typargs.isEmpty) "" else "," + typargs) + ")"
}
case class Free(name: String, typ: Typ = dummyT) extends Term
{
override def toString: String =
"Free(" + name + (if (typ == dummyT) "" else "," + typ) + ")"
}
case class Var(name: Indexname, typ: Typ = dummyT) extends Term
{
override def toString: String =
"Var(" + name + (if (typ == dummyT) "" else "," + typ) + ")"
}
case class Bound(index: Int) extends Term
case class Abs(name: String, typ: Typ, body: Term) extends Term
case class App(fun: Term, arg: Term) extends Term
{
override def toString: String =
this match {
case OFCLASS(ty, c) => "OFCLASS(" + ty + "," + c + ")"
case _ => "App(" + fun + "," + arg + ")"
}
}
def dummy_pattern(ty: Typ): Term = Const("Pure.dummy_pattern", List(ty))
val dummy: Term = dummy_pattern(dummyT)
sealed abstract class Proof
case object MinProof extends Proof
case class PBound(index: Int) extends Proof
case class Abst(name: String, typ: Typ, body: Proof) extends Proof
case class AbsP(name: String, hyp: Term, body: Proof) extends Proof
case class Appt(fun: Proof, arg: Term) extends Proof
case class AppP(fun: Proof, arg: Proof) extends Proof
case class Hyp(hyp: Term) extends Proof
case class PAxm(name: String, types: List[Typ]) extends Proof
case class PClass(typ: Typ, cls: Class) extends Proof
case class Oracle(name: String, prop: Term, types: List[Typ]) extends Proof
case class PThm(serial: Long, theory_name: String, name: String, types: List[Typ]) extends Proof
/* type classes within the logic */
object Class_Const
{
val suffix = "_class"
def apply(c: Class): String = c + suffix
def unapply(s: String): Option[Class] =
if (s.endsWith(suffix)) Some(s.substring(0, s.length - suffix.length)) else None
}
object OFCLASS
{
def apply(ty: Typ, s: Sort): List[Term] = s.map(c => apply(ty, c))
def apply(ty: Typ, c: Class): Term =
App(Const(Class_Const(c), List(ty)), Const(Pure_Thy.TYPE, List(ty)))
def unapply(t: Term): Option[(Typ, String)] =
t match {
case App(Const(Class_Const(c), List(ty)), Const(Pure_Thy.TYPE, List(ty1)))
if ty == ty1 => Some((ty, c))
case _ => None
}
}
/** cache **/
def make_cache(initial_size: Int = 131071, max_string: Int = Integer.MAX_VALUE): Cache =
new Cache(initial_size, max_string)
class Cache private[Term](initial_size: Int, max_string: Int)
extends isabelle.Cache(initial_size, max_string)
{
protected def cache_indexname(x: Indexname): Indexname =
lookup(x) getOrElse store(Indexname(cache_string(x.name), x.index))
protected def cache_sort(x: Sort): Sort =
if (x.isEmpty) Nil else lookup(x) getOrElse store(x.map(cache_string))
protected def cache_typ(x: Typ): Typ =
{
if (x == dummyT) dummyT
else
lookup(x) match {
case Some(y) => y
case None =>
x match {
case Type(name, args) => store(Type(cache_string(name), cache_typs(args)))
case TFree(name, sort) => store(TFree(cache_string(name), cache_sort(sort)))
case TVar(name, sort) => store(TVar(cache_indexname(name), cache_sort(sort)))
}
}
}
protected def cache_typs(x: List[Typ]): List[Typ] =
{
if (x.isEmpty) Nil
else {
lookup(x) match {
case Some(y) => y
case None => store(x.map(cache_typ))
}
}
}
protected def cache_term(x: Term): Term =
{
lookup(x) match {
case Some(y) => y
case None =>
x match {
case Const(name, typargs) => store(Const(cache_string(name), cache_typs(typargs)))
case Free(name, typ) => store(Free(cache_string(name), cache_typ(typ)))
case Var(name, typ) => store(Var(cache_indexname(name), cache_typ(typ)))
case Bound(_) => store(x)
case Abs(name, typ, body) =>
store(Abs(cache_string(name), cache_typ(typ), cache_term(body)))
case App(fun, arg) => store(App(cache_term(fun), cache_term(arg)))
}
}
}
protected def cache_proof(x: Proof): Proof =
{
if (x == MinProof) MinProof
else {
lookup(x) match {
case Some(y) => y
case None =>
(x: @unchecked) match {
case PBound(_) => store(x)
case Abst(name, typ, body) =>
store(Abst(cache_string(name), cache_typ(typ), cache_proof(body)))
case AbsP(name, hyp, body) =>
store(AbsP(cache_string(name), cache_term(hyp), cache_proof(body)))
case Appt(fun, arg) => store(Appt(cache_proof(fun), cache_term(arg)))
case AppP(fun, arg) => store(AppP(cache_proof(fun), cache_proof(arg)))
case Hyp(hyp) => store(Hyp(cache_term(hyp)))
case PAxm(name, types) => store(PAxm(cache_string(name), cache_typs(types)))
case PClass(typ, cls) => store(PClass(cache_typ(typ), cache_string(cls)))
case Oracle(name, prop, types) =>
store(Oracle(cache_string(name), cache_term(prop), cache_typs(types)))
case PThm(serial, theory_name, name, types) =>
store(PThm(serial, cache_string(theory_name), cache_string(name), cache_typs(types)))
}
}
}
}
// main methods
def indexname(x: Indexname): Indexname = synchronized { cache_indexname(x) }
def sort(x: Sort): Sort = synchronized { cache_sort(x) }
def typ(x: Typ): Typ = synchronized { cache_typ(x) }
def term(x: Term): Term = synchronized { cache_term(x) }
def proof(x: Proof): Proof = synchronized { cache_proof(x) }
def position(x: Position.T): Position.T =
synchronized { x.map({ case (a, b) => (cache_string(a), cache_string(b)) }) }
}
}