private PtUse?TryUse()
{
if (MayBegin(TK.Use))
{
var name = TryUseName();
if (Iss(TK.At))
{
Match(TK.At);
var ffiName = FfiName();
var returnType = TypeArguments();
var parameters = Parameters();
var partial = MayPartial();
var guard = TryUseGuard();
var use = new PtUseFfi(End(), name, ffiName, returnType, parameters, partial, guard);
return(use);
}
else if (Iss(TK.String))
{
var uri = String();
var guard = TryUseGuard();
return(new PtUseUri(End(), name, uri, guard));
}
}
return(null);
}
public ForeignFunctionDeclaration(PtUseFfi source, string name, ForeignParameters parameters, IType result)
{
Source = source;
Name = name;
Parameters = parameters;
Result = result;
}
public UseForeignFunction(PtUseFfi source, ForeignFunctionDeclaration function)
{
Source = source;
Function = function;
}
protected virtual void DoVisit(PtUseFfi node) => VisitChildren(node);
protected override void DoVisit(PtUseFfi node)
{
Ffis.Add($"use {node.FfiName}");
}
private IUse DecodeUseFfi(PtUseFfi use)
{
if (use.Name != null)
{
throw new System.NotImplementedException();
}
if (use.Partial)
{
throw new System.NotImplementedException();
}
string name;
if (use.FfiName.Name is PtString str)
{
name = str.Value;
}
else if (use.FfiName.Name is PtIdentifier id)
{
name = id.Value;
}
else
{
throw new System.InvalidOperationException();
}
if (use.TypeArguments.Arguments.Count != 1)
{
Errors.Help.Add(
use.TypeArguments.Span,
ErrNo.Err005,
"return of a foreign function call must have exactly one type");
}
var result = new AnyType(use.TypeArguments.Arguments[0]);
var items = new List <Parameter>();
bool ellipsis = false;
foreach (var prm in use.Parameters.Items)
{
if (ellipsis)
{
Errors.Help.Add(
use.Parameters.Items.OfType <PtEllipsisParameter>().First().Span,
ErrNo.Err004,
"ellipis ``...´´ must be last in foreign function declaration");
}
switch (prm)
{
case PtEllipsisParameter ell:
ellipsis = true;
break;
case PtRegularParameter reg:
items.Add(new Parameter(reg, reg.Name.Value, new AnyType(reg.Type), reg.Value == null ? null : new AnyExpression(reg.Value)));
break;
}
}
var parameters = new ForeignParameters(use.Parameters, items, ellipsis);
var function = new ForeignFunctionDeclaration(use, name, parameters, result);
return(new UseForeignFunction(use, function));
}
