private void _expandPartialApplication(MacroContext context, int passThrough,
List<AstExpr> arguments)
{
var flatArgs = new List<AstExpr>(arguments.Count);
var directives = new List<int>(arguments.Count);
//The call target is a "non-argument" in partial application terms. Do not include it in the
// stream of directives.
flatArgs.Add(arguments[0]);
var opaqueSpan = 0;
for (var i = 1; i < arguments.Count; i++)
{
var arg = arguments[i];
AstListLiteral lit;
if (i < passThrough || !_isPartialList(arg, out lit))
{
flatArgs.Add(arg);
opaqueSpan++;
}
else
{
flatArgs.AddRange(lit.Elements);
if (opaqueSpan > 0)
{
directives.Add(opaqueSpan);
opaqueSpan = 0;
}
directives.Add(-lit.Elements.Count);
}
}
var ppArgv = AstPartiallyApplicable.PreprocessPartialApplicationArguments(flatArgs);
var argc = ppArgv.Count;
var mappings8 = new int[argc + directives.Count + 1];
var closedArguments = new List<AstExpr>(argc);
AstPartiallyApplicable.GetMapping(ppArgv, mappings8, closedArguments);
_mergeDirectivesIntoMappings(directives, mappings8, argc);
var mappings32 = PartialApplicationCommandBase.PackMappings32(mappings8);
var implCall = context.Factory.Call(context.Invocation.Position,
EntityRef.Command.Create(PartialCallStarImplCommand.Alias), context.Call);
implCall.Arguments.AddRange(closedArguments);
implCall.Arguments.AddRange(mappings32.Select(m => context.CreateConstant(m)));
context.Block.Expression = implCall;
}
private static AstGetSet _assembleImplCall(MacroContext context, SymbolEntry implementationSymbolEntry,
ISourcePosition position)
{
var internalId = context.CreateConstant(implementationSymbolEntry.InternalId);
var interpretation = implementationSymbolEntry.Interpretation.ToExpr(position);
var moduleNameOpt = context.CreateConstantOrNull(implementationSymbolEntry.Module);
var implCall = context.Factory.IndirectCall(context.Invocation.Position,
context.Factory.Reference(context.Invocation.Position,
EntityRef.Command.Create(
Impl.Alias)));
implCall.Arguments.Add(internalId);
implCall.Arguments.Add(interpretation);
implCall.Arguments.Add(moduleNameOpt);
return implCall;
}
protected override void DoExpand(MacroContext context)
{
if (context.Invocation.Arguments.Count == 0)
{
// Call with no arguments returns null.
// The macro system will supply that null.
return;
}
var p = context.Invocation.Arguments[0] as AstPlaceholder;
if (context.Invocation.Arguments.Count == 1
&& p != null
&& (p.Index.GetValueOrDefault(0) == 0))
{
// call(?0) ⇒ call\perform(?0)
context.Block.Expression = GetTrivialPartialApplication(context);
return;
}
if (!context.Invocation.Arguments.Any(_hasPlaceholder))
{
// no placeholders, invoke call\perform directly
var call = context.Factory.IndirectCall(context.Invocation.Position,
context.Factory.Reference(context.Invocation.Position,
_callImplementation),
context.Call);
call.Arguments.AddRange(GetCallArguments(context));
context.Block.Expression = call;
return;
}
// Assemble the invocation of call\*(passThrough,call\perform(?),callArguments...)
// Note: this is a get-call in all cases, because we are computing a partial application
// whether the programmer wrote a get or a set call needs to be captured by concrete
// implementations of partial call wrapers (see Call_Member)
var inv = context.Factory.Expand(context.Invocation.Position, EntityRef.MacroCommand.Create(CallStar.Instance.Id));
// Protect the first two arguments
inv.Arguments.Add(context.CreateConstant(GetPassThroughArguments(context)));
// Indicate the kind of call by passing `call\perform(?)`, a partial application of call
var paCall = context.Factory.Call(context.Invocation.Position, _callImplementation, context.Call,
new AstPlaceholder(context.Invocation.File, context.Invocation.Line,
context.Invocation.Column, 0));
inv.Arguments.Add(paCall);
// Pass all the other arguments through
inv.Arguments.AddRange(GetCallArguments(context));
context.Block.Expression = inv;
}