/*
* Find a type by name. If the type is not found, a new type
* is created with status NAMED.
*/
internal static XType Lookup(string name)
{
/*
* std::string is an alias for (std::u8 std::array).
* TODO: design and implement a more generic alias system
* for types.
*/
if (name == "std::string")
{
return(ARRAY_U8);
}
XType xt;
if (!ALL.TryGetValue(name, out xt))
{
xt = new XType(name);
ALL[name] = xt;
}
return(xt);
}
/*
* Find an array type, for a given element type. If the array type
* is not found, it is automatically created.
*/
internal static XType LookupArray(XType elementType, bool embed)
{
string name = string.Format("({0} {1})",
elementType.Name,
embed ? "std::array&" : "std::array");
XType xt;
if (!ALL.TryGetValue(name, out xt))
{
if (embed && !elementType.IsEmbeddable)
{
throw new Exception(string.Format("type {0} is not embeddable", elementType.Name));
}
xt = new XType(name);
xt.arrayElementType = elementType;
xt.arrayElementEmbedded = embed;
xt.CloseArray();
ALL[name] = xt;
XType[] tArray = new XType[] { xt };
XType[] tIntArray = new XType[] { INT, xt };
XType[] tIntIntArray = new XType[] { INT, INT, xt };
XType[] tIntIntArrayArray = new XType[] {
INT, INT, xt, xt
};
XType[] tEltIntArray = new XType[] {
elementType, INT, xt
};
XType[] tArrayArray = new XType[] { xt, xt };
Function.Register("std::sub", tIntIntArrayArray,
new NativeArrayAccessorSub(xt));
Function.Register("std::subself", tIntIntArray,
new NativeArrayAccessorSubSelf(xt));
Function.Register("std::init?", tArray,
new NativeArrayAccessorIsInit(xt));
Function.Register("std::length", tArray,
new NativeArrayAccessorLength(xt));
if (embed)
{
Function.Register("std::make", tIntArray,
new NativeArrayAccessorMakeEmbed(xt));
Function.Register("std::@&", tIntArray,
new NativeArrayAccessorRef(xt));
}
else
{
Function.Register("std::make", tIntArray,
new NativeArrayAccessorMakeRef(xt));
Function.Register("std::@", tIntArray,
new NativeArrayAccessorGet(xt));
Function.Register("std::->@", tEltIntArray,
new NativeArrayAccessorPut(xt));
Function.Register("std::Z->@", tIntArray,
new NativeArrayAccessorPut(xt));
Function.Register("std::@?", tIntArray,
new NativeArrayAccessorIsEltInit(xt));
/*
* Arrays of references implement '=' by
* running that function on all elements.
* This is implemented with an interpreted
* function since it may call interpreted
* functions.
*
* : = (...)
* ->{ a1 a2 }
* a1 length ->{ len }
* len a2 length = ifnot false ret then
* 0 ->{ i }
* begin i len < while
* i a1 @ i a2 @ = ifnot false ret then
* i ++ ->i
* repeat
* true ;
*/
FunctionBuilder fb = new FunctionBuilder(
"std::=");
/* { a1 a2 len i } */
fb.DefLocalField("a1", null);
fb.DefLocalField("a2", null);
fb.DefLocalField("len", null);
fb.DefLocalField("i", null);
/* ->{ a1 a2 } */
fb.DoLocal("->a2");
fb.DoLocal("->a1");
/* a1 length ->len */
fb.DoLocal("a1");
fb.Call("std::length");
fb.DoLocal("->len");
/* len a2 length = ifnot false ret then */
fb.DoLocal("len");
fb.DoLocal("a2");
fb.Call("std::length");
fb.Call("std::=");
fb.AheadIf();
fb.Literal(false);
fb.Ret();
fb.Then();
/* 0 ->{ i } */
fb.Literal(XValue.MakeInt(0));
fb.DoLocal("->i");
/* begin i len < while */
fb.Begin();
fb.DoLocal("i");
fb.DoLocal("len");
fb.Call("std::<");
fb.AheadIfNot();
fb.CSRoll(1);
/* i a1 @ i a2 @ = ifnot false ret then */
fb.DoLocal("i");
fb.DoLocal("a1");
fb.Call("std::@");
fb.DoLocal("i");
fb.DoLocal("a2");
fb.Call("std::@");
fb.Call("std::=");
fb.AheadIf();
fb.Literal(false);
fb.Ret();
fb.Then();
/* i ++ ->i */
fb.DoLocal("i");
fb.Call("std::++");
fb.DoLocal("->i");
/* repeat */
fb.Again();
fb.Then();
/* true ; */
fb.Literal(true);
fb.Ret();
Function f = fb.Build();
Function.Register("std::=", tArrayArray, f);
/*
* The std::<> function is implemented by
* calling std::=, then negating.
*/
fb = new FunctionBuilder(
"std::<>");
fb.Call("std::=");
fb.Call("std::not");
fb.Ret();
f = fb.Build();
Function.Register("std::<>", tArrayArray, f);
}
}
else if (xt.arrayElementType != elementType)
{
throw new Exception(string.Format("type {0} already exists and is not an array of {1}", name, elementType.Name));
}
else if (xt.arrayElementEmbedded != embed)
{
throw new Exception(string.Format("elements of type {0} are {1}embedded", name, embed ? "not " : ""));
}
return(xt);
}