public override void Visit(AST_assignment assignment)
{
assignment.Expression.Accept(this);
Variable var = variables.GetValueOrDefault(assignment.Identifier.Name);
var.Set(value);
}
private AST_assignment Parse_assignment(TokenKind followSet)
{
IncrementDepth();
AST_assignment assignment;
AST_identifier identifier;
AST_expression expression = null;
identifier = Parse_identifier(Assignment);
if (!Match(Assignment))
{
Error("':=' expected.", lastReadToken);
if (LookAheadToken().Kind != Semicolon)
{
// Assume an incorrect assignment symbol and skip over it
GetNextToken();
}
}
expression = Parse_expression(Semicolon);
assignment = new AST_assignment(identifier, expression);
DecrementDepth();
return(assignment);
}
public virtual void Visit(AST_assignment assignment)
{
IncrementDepth();
assignment.Identifier.Accept(this);
assignment.Expression.Accept(this);
DecrementDepth();
}
override public void Visit(AST_assignment assignment)
{
base.Visit(assignment);
string name = assignment.Identifier.Name;
if (variables.ContainsKey(name))
{
if (assignment.Expression.DataType == variables.GetValueOrDefault(name).Type.Kind)
{
if (loopVariables.ContainsKey(name))
{
Error("'" + name + "' is a loop variable, assignment not allowed.", assignment.Identifier);
}
}
else
{
Error("Type mismatch in assignment.", assignment);
}
}
else
{
Error("Variable '" + name + "' has not been declared.", assignment);
}
}
public override void Visit(AST_assignment assignment)
{
assignment.Accept(evaluateVisitor);
}