public override int VisitVariableedit([NotNull] CBluntParser.VariableeditContext context)
{
#if DEBUG
Console.WriteLine("VisitVariableedit");
#endif
this.AddText(context.ID().GetText());
Visit(context.equals());
Visit(context.expression());
return(0);
}
/// <summary>
/// Visit a parse tree produced by <see cref="CBluntParser.variableedit"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitVariableedit([NotNull] CBluntParser.VariableeditContext context)
{
return(VisitChildren(context));
}
public override int VisitVariableedit([NotNull] CBluntParser.VariableeditContext context)
{
#if DEBUG
Console.WriteLine("VisitVariableedit");
#endif
// The name of the variable
var variableName = context.ID().GetText();
// The operator type (For example: = += /= so on)
var operatorType = context.equals().GetText();
// The assignment value
var assignmentValue = context.expression().GetText();
/// TODO: USE UTILITY METHOD
// First iterate over the current scope and all previous scopes
var currNode = SymbolTable.MethodScopeLinkedList.Last;
// The properties of the variable we found
VariableProperties variableProperties = null;
variableProperties = GetDeclaredVariable(variableName);
if (variableProperties == null)
{
SyntaxError(context, "Variable with name " + variableName + " cannot be assigned a value as it does not exist");
return(1);
}
// Get the expected assignment value, aka the value we expect the variable to be assigned
SymbolTable.ExpressionStoreLinkedList.AddLast(new ExpressionStore());
Visit(context.expression());
// Set assignment type from expression, compare it against operator type
var assignmentType = SymbolTable.ExpressionStoreLinkedList.Last.Value.Type;
SymbolTable.ExpressionStoreLinkedList.RemoveLast();
switch (operatorType)
{
// Always allow default assignment
case "=":
break;
case "+=":
if (assignmentType != "number")
{
SyntaxError(context, "Cannot use addition assignment operator on a type " + assignmentType);
return(1);
}
break;
case "-=":
if (assignmentType != "number")
{
SyntaxError(context, "Cannot use subtraction assignment operator on a type " + assignmentType);
return(1);
}
break;
case "*=":
if (assignmentType != "number")
{
SyntaxError(context, "Cannot use multiplication assignment operator on a type " + assignmentType);
return(1);
}
break;
case "/=":
if (assignmentType != "number")
{
SyntaxError(context, "Cannot use division assignment operator on a type " + assignmentType);
return(1);
}
break;
}
// Now test if this variable's type is the type we are trying to assign
if (variableProperties.Type != assignmentType)
{
SyntaxError(context, "Variable " + variableName + " is of type " + variableProperties.Type + ", cannot assign it a value of type " + assignmentType);
return(1);
}
// If all checks passes, the variable will also be initialized
variableProperties.Initialized = true;
return(0);
}