/// <summary>
/// Parses a function declaration
/// Syntax:
/// returntype identifer ( param_list )
/// {
/// statements
/// }
/// </summary>
public FunctionInfo ParseFunctionDeclaration()
{
Int32 type = -1;
type = ParseType();
//Validity
if (CurrentToken.Type != TokenType.Identifier)
Error("Invalid function name", CurrentToken.LineStart);
FunctionInfo func = new FunctionInfo();
func.Name = CurrentToken.Value;
func.Type = type;
List<String> paramNames = new List<String>();
NextToken();
NextToken();
if (CurrentToken.Value != ")")
{
while (true)
{
VariableInfo var = new VariableInfo();
ParseDeclaration(ref var);
if (!"),".Contains(CurrentToken.Value))
Error("Expected comma as param seperator", CurrentToken.LineStart);
if (paramNames.Contains(var.Name))
Error("Already got parameter", CurrentToken.LineStart, CurrentToken.CharacterPosition);
paramNames.Add(var.Name);
func.Parameters.Add(var);
if (CurrentToken.Value.Equals(")"))
break;
if (CurrentToken.Value.Equals(","))
NextToken();
}
}
NextToken();
return func;
}
public void ParseDeclaration(ref VariableInfo var)
{
if (!Database.CheckType(CurrentToken.Value))
Error("Invalid type", CurrentToken.LineStart, CurrentToken.CharacterPosition);
Int32 type = ParseType();
//Check for validity in name
if (!CurrentToken.Type.Equals(TokenType.Identifier))
Error("Invalid Name: " + CurrentToken.Value, CurrentToken.LineStart, CurrentToken.CharacterPosition);
if (!Database.CheckValidName(CurrentToken.Value))
Error("Invalid Name, name already used: " + CurrentToken.Value,
CurrentToken.LineStart,
CurrentToken.CharacterPosition);
String name = CurrentToken.Value;
NextToken();
var.Name = name;
var.Type = type;
}
/// <summary>
/// Parse a type
/// Syntax:
/// struct type_name
/// {
/// datatype identifier;
/// ...
/// }
/// </summary>
public void ParseTypeDeclaration()
{
//Ignore the word TYPE
NextToken();
if (CurrentToken.Type != TokenType.Identifier || !Database.CheckValidName(CurrentToken.Value))
Error("Invalid Type Name", CurrentToken.LineStart);
//Set type info
TypeInfo type = new TypeInfo();
type.Name = CurrentToken.Value;
//Keep a record of all the members to ensure none are repeated
List<String> memberNames = new List<String>();
NextToken();
if (CurrentToken.Value != "{")
Error("Expected member list { ... }", CurrentToken.LineStart);
//NEW and DELETE of the type are functions, if they are incoming, skip and parse later
while (CheckFunctionIncoming())
{
SkipBlock();
NextToken();
}
NextToken();
//Get member declarations
do
{
VariableInfo var = new VariableInfo();
ParseDeclaration(ref var);
//Check if valid member
if (memberNames.Contains(var.Name))
Error("Type " + type.Name + " already contains a member named " + var.Name,
CurrentToken.LineStart);
memberNames.Add(var.Name);
//If the next token isn't a semicolon we have an error
if (CurrentToken.Value != ";")
{
Error("Expected semicolon", CurrentToken.LineStart);
}
NextToken();
//Skip any function
while (CheckFunctionIncoming())
{
SkipBlock();
NextToken();
}
//Add new member to the members list
type.Members.Add(var);
} while (CurrentToken.Value != "}");
//Add the new type to the database
Database.AddType(type);
NextToken();
}
/// <summary>
/// Parses all global variable declarations (not in functions or structs)
/// Syntax:
/// datatype identifier;
/// </summary>
public void ParseGlobalVariableDeclarations()
{
for (int Line = 0; Line < Lines && CurrentToken != null; Line++)
{
if (CurrentToken.Value != ";")
{
if (CurrentToken.Value.Equals("STRUCT") || CheckFunctionIncoming())
{
SkipBlock();
PreviousToken();
}
else if (Database.CheckType(CurrentToken.Value))
{
VariableInfo var = new VariableInfo();
ParseDeclaration(ref var);
Database.AddVariable(var, null);
}
}
NextToken();
}
}
private void ParseVariableDeclaration(ref Node node)
{
VariableInfo var = new VariableInfo();
ParseDeclaration(ref var);
node = new Node();
node.Value = "DECLARE";
node.Attributes[0] = Database.GetVarId(var.Name, null);
node.Attributes[1] = Database.GetTypeName(var.Type);
}
/// <summary>
/// Adds a variable to the variable list
/// </summary>
public static void AddVariable(VariableInfo var, Scope scope)
{
if (scope != null)
var.Id = scope.Id + var.Name;
else
{
scope = CurrentScope;
var.Id = var.Name;
}
scope.Variables.Add(var);
}