private ILanguageExpressionAtomic CompileRhsValueAccess(LanguageValueAccess valueAccess)
{
var compiledRootSymbol = valueAccess.RootSymbol;
//Replace a reference to a constant by its value
var namedValue = compiledRootSymbol as SymbolNamedValue;
if (namedValue != null)
{
var compiledFullValue = namedValue.AssociatedValue;
return
(valueAccess.IsFullAccess
? compiledFullValue.DuplicateValue(true)
: ValueAccessProcessor.ReadPartialValue(compiledFullValue, valueAccess).DuplicateValue(true));
}
if (compiledRootSymbol is SymbolLocalVariable || compiledRootSymbol is SymbolProcedureParameter)
{
compiledRootSymbol = GetSymbolData((SymbolDataStore)compiledRootSymbol);
}
var compiledValueAccess = LanguageValueAccess.Create(compiledRootSymbol);
if (valueAccess.IsPartialAccess)
{
//Note: This will not be correct for components of class ValueAccessStepBySymbol
//because the component symbol must be compiled too. But GMac doesn't use these components anyway
compiledValueAccess.Append(valueAccess.PartialAccessSteps);
}
return(compiledValueAccess);
}
/// <summary>
/// Read the value associated with a value access process
/// </summary>
/// <param name="valueAccess"></param>
/// <returns></returns>
public virtual ILanguageValue Visit(LanguageValueAccess valueAccess)
{
var value = ReadSymbolFullValue(valueAccess.RootSymbol);
return
(valueAccess.IsFullAccess ?
value :
ValueAccessProcessor.ReadPartialValue(value, valueAccess));
}
/// <summary>
/// Update the full or partial value of a symbol (if allowed) depending on the given value access
/// </summary>
/// <param name="valueAccess"></param>
/// <param name="value"></param>
protected virtual void UpdateSymbolValue(LanguageValueAccess valueAccess, ILanguageValue value)
{
var symbol = valueAccess.RootSymbol;
if (AllowUpdateSymbolValue(symbol) == false)
{
throw new InvalidOperationException("Invalid symbol type");
}
if (valueAccess.IsFullAccess)
{
SetSymbolData((SymbolDataStore)symbol, value);
return;
}
var sourceValue = ReadSymbolFullValue(symbol);
ValueAccessProcessor.WritePartialValue(sourceValue, valueAccess, value);
}
/// <summary>
/// Evaluate a structure construction operation
/// </summary>
/// <param name="structureCons"></param>
/// <param name="operands"></param>
/// <returns></returns>
private ValueStructureSparse EvaluateBasicPolyadicStructureConstructor(GMacStructureConstructor structureCons, OperandsByValueAccess operands)
{
ValueStructureSparse value;
if (structureCons.HasDefaultValueSource)
{
value =
(ValueStructureSparse)structureCons
.DefaultValueSource
.AcceptVisitor(this)
.DuplicateValue(true);
}
else
{
value =
(ValueStructureSparse)GMacRootAst
.CreateDefaultValue(structureCons.Structure);
}
foreach (var command in operands.AssignmentsList)
{
var rhsValue = command.RhsExpression.AcceptVisitor(this);
if (command.LhsValueAccess.IsFullAccess)
{
value[command.LhsValueAccess.RootSymbol.ObjectName] = rhsValue.DuplicateValue(true);
}
else
{
var sourceValue = value[command.LhsValueAccess.RootSymbol.ObjectName];
ValueAccessProcessor.WritePartialValue(sourceValue, command.LhsValueAccess, rhsValue.DuplicateValue(true));
}
}
return(value);
}
