public ASTNode ParseBody()
{
do
{
if (Tokens.CurrentItem.StartPosition.Equals(Body.StartPos))
{
break;
}
Tokens.Advance();
} while (!Tokens.AtEnd());
if (Tokens.AtEnd())
{
return(Error("Could not find the code body for the current node, please contact the maintainers of this compiler!"));
}
var body = TryParseBody(false);
if (body == null)
{
return(null);
}
Body.Statements = body.Statements;
if (!Tokens.CurrentItem.StartPosition.Equals(Body.EndPos))
{
return(Error("Could not parse a valid statement, even though the current code body has supposedly not ended yet.",
CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
return(Body);
}
/// <summary>
/// Skip tokens until we reach what we assume to be the end of a statement
/// </summary>
// TODO does this belong on a statement parser or something
private void SkipToEndOfStatement()
{
while (!Tokens.AtEnd <ISemicolonToken>())
{
Tokens.Next();
}
// Consume the semicolon is we aren't at the end of the file.
var _ = Tokens.Accept <ISemicolonToken>();
}
public FixedList <T> ParseMany <T, TTerminator>(Func <T> parseItem)
where T : class
where TTerminator : IToken
{
var items = new List <T>();
while (!Tokens.AtEnd <TTerminator>())
{
items.Add(parseItem());
}
return(items.ToFixedList());
}
/// <summary>
/// Requires that the open paren has already been consumed
/// </summary>
/// <returns></returns>
private FixedList <ParameterSyntax> ParseRestOfParameters()
{
var parameters = new List <ParameterSyntax>();
while (!Tokens.AtEnd <ICloseParenToken>())
{
parameters.Add(ParseParameter());
if (Tokens.Current is ICommaToken)
{
Tokens.Expect <ICommaToken>();
}
}
Tokens.Expect <ICloseParenToken>();
return(parameters.ToFixedList());
}
private FixedList <EnumVariantSyntax> ParseEnumVariants()
{
var variants = new List <EnumVariantSyntax>();
while (Tokens.Current is IIdentifierToken)
{
variants.Add(ParseEnumVariant());
}
// Semicolon is optional if there are no members
if (!Tokens.AtEnd <ICloseBraceToken>())
{
Tokens.Expect <ISemicolonToken>();
}
return(variants.ToFixedList());
}
public Struct TryParseStruct()
{
Func <ASTNode> structParser = () =>
{
if (Tokens.ConsumeToken(TokenType.Struct) == null)
{
return(null);
}
var specs = ParseSpecifiers(GlobalLists.StructSpecifiers);
var name = Tokens.ConsumeToken(TokenType.Word);
if (name == null)
{
return(Error("Expected struct name!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
var parent = TryParseParent();
if (Tokens.ConsumeToken(TokenType.LeftBracket) == null)
{
return(Error("Expected '{'!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
var vars = new List <VariableDeclaration>();
do
{
var variable = TryParseVarDecl();
if (variable == null)
{
return(Error("Malformed struct content!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
vars.Add(variable);
} while (CurrentTokenType != TokenType.RightBracket && !Tokens.AtEnd());
if (Tokens.ConsumeToken(TokenType.RightBracket) == null)
{
return(Error("Expected '}'!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
return(new Struct(name.Value, specs, vars, name.StartPosition, name.EndPosition, parent));
};
return((Struct)Tokens.TryGetTree(structParser));
}
public FixedList <T> ParseMany <T, TSeparator, TTerminator>(Func <T> parseItem)
where T : class
where TSeparator : class, IToken
where TTerminator : IToken
{
var items = new List <T>();
while (!Tokens.AtEnd <TTerminator>())
{
items.Add(parseItem());
if (!Tokens.Accept <TSeparator>())
{
break;
}
}
return(items.ToFixedList());
}
public FixedList <DeclarationSyntax> ParseDeclarations()
{
var declarations = new List <DeclarationSyntax>();
// Stop at end of file or close brace that contains these declarations
while (!Tokens.AtEnd <ICloseBraceToken>())
{
try
{
declarations.AddRange(ParseDeclaration());
}
catch (ParseFailedException)
{
// Ignore: we would have consumed something before failing, try to get the next declaration
}
}
return(declarations.ToFixedList());
}
public FixedList <DeclarationSyntax> ParseTopLevelDeclarations()
{
var declarations = new List <DeclarationSyntax>();
// Keep going to the end of the file
while (!Tokens.AtEnd <IEndOfFileToken>())
{
try
{
declarations.AddRange(ParseDeclaration());
}
catch (ParseFailedException)
{
// Ignore: we would have consumed something before failing, try to get the next declaration
}
}
return(declarations.ToFixedList());
}
public FixedList <INonMemberDeclarationSyntax> ParseNonMemberDeclarations <T>()
where T : IToken
{
var declarations = new List <INonMemberDeclarationSyntax>();
// Stop at end of file or some token that contains these declarations
while (!Tokens.AtEnd <T>())
{
try
{
declarations.Add(ParseNonMemberDeclaration());
}
catch (ParseFailedException)
{
// Ignore: we would have consumed something before failing, try to get the next declaration
}
}
return(declarations.ToFixedList());
}
public State TryParseState()
{
Func <ASTNode> stateSkeletonParser = () =>
{
var specs = ParseSpecifiers(GlobalLists.StateSpecifiers);
if (Tokens.ConsumeToken(TokenType.State) == null)
{
return(null);
}
var name = Tokens.ConsumeToken(TokenType.Word);
if (name == null)
{
return(Error("Expected state name!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
var parent = TryParseParent();
if (Tokens.ConsumeToken(TokenType.LeftBracket) == null)
{
return(Error("Expected '{'!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
List <Function> ignores = new List <Function>();
if (Tokens.ConsumeToken(TokenType.Ignores) != null)
{
do
{
VariableIdentifier variable = TryParseVariable();
if (variable == null)
{
return(Error("Malformed ignore statement!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
ignores.Add(new Function(variable.Name, null, null, null, null, variable.StartPos, variable.EndPos));
} while (Tokens.ConsumeToken(TokenType.Comma) != null);
if (Tokens.ConsumeToken(TokenType.SemiColon) == null)
{
return(Error("Expected semi-colon!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
}
var funcs = new List <Function>();
Function func = TryParseFunction();
while (func != null)
{
funcs.Add(func);
func = TryParseFunction();
}
var bodyStart = Tokens.CurrentItem.StartPosition;
while (Tokens.CurrentItem.Type != TokenType.RightBracket && !Tokens.AtEnd())
{
Tokens.Advance();
}
var bodyEnd = Tokens.CurrentItem.StartPosition;
if (Tokens.ConsumeToken(TokenType.RightBracket) == null)
{
return(Error("Expected '}'!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
var body = new CodeBody(new List <Statement>(), bodyStart, bodyEnd);
var parentState = parent != null ? new State(parent.Name, null, null, null, null, null, null, parent.StartPos, parent.EndPos) : null;
return(new State(name.Value, body, specs, parentState, funcs, ignores, null, name.StartPosition, name.EndPosition));
};
return((State)Tokens.TryGetTree(stateSkeletonParser));
}
public Class TryParseClass()
{
Func <ASTNode> classParser = () =>
{
if (Tokens.ConsumeToken(TokenType.Class) == null)
{
return(Error("Expected class declaration!"));
}
var name = Tokens.ConsumeToken(TokenType.Word);
if (name == null)
{
return(Error("Expected class name!"));
}
var parentClass = TryParseParent();
if (parentClass == null)
{
Log.LogMessage("No parent class specified for " + name.Value + ", interiting from Object");
parentClass = new VariableType("Object", null, null);
}
var outerClass = TryParseOuter();
var specs = ParseSpecifiers(GlobalLists.ClassSpecifiers);
if (Tokens.ConsumeToken(TokenType.SemiColon) == null)
{
return(Error("Expected semi-colon!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
var variables = new List <VariableDeclaration>();
var types = new List <VariableType>();
while (CurrentTokenType == TokenType.InstanceVariable ||
CurrentTokenType == TokenType.Struct ||
CurrentTokenType == TokenType.Enumeration)
{
if (CurrentTokenType == TokenType.InstanceVariable)
{
var variable = TryParseVarDecl();
if (variable == null)
{
return(Error("Malformed instance variable!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
variables.Add(variable);
}
else
{
var type = TryParseEnum() ?? TryParseStruct() ?? new VariableType("INVALID", null, null);
if (type.Name == "INVALID")
{
return(Error("Malformed type declaration!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
types.Add(type);
if (Tokens.ConsumeToken(TokenType.SemiColon) == null)
{
return(Error("Expected semi-colon!", CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
}
}
List <Function> funcs = new List <Function>();
List <State> states = new List <State>();
List <OperatorDeclaration> ops = new List <OperatorDeclaration>();
ASTNode declaration;
do
{
declaration = (ASTNode)TryParseFunction() ??
(ASTNode)TryParseOperatorDecl() ??
(ASTNode)TryParseState() ??
(ASTNode)null;
if (declaration == null && !Tokens.AtEnd())
{
return(Error("Expected function/state/operator declaration!",
CurrentPosition, CurrentPosition.GetModifiedPosition(0, 1, 1)));
}
if (declaration.Type == ASTNodeType.Function)
{
funcs.Add((Function)declaration);
}
else if (declaration.Type == ASTNodeType.State)
{
states.Add((State)declaration);
}
else
{
ops.Add((OperatorDeclaration)declaration);
}
} while (!Tokens.AtEnd());
// TODO: should AST-nodes accept null values? should they make sure they dont present any?
return(new Class(name.Value, specs, variables, types, funcs, states, parentClass, outerClass, ops, name.StartPosition, name.EndPosition));
};
return((Class)Tokens.TryGetTree(classParser));
}
