private Executable ParseContinue(TokenStream tokens, TopLevelConstruct owner)
{
Token continueToken = tokens.PopExpected(this.parser.Keywords.CONTINUE);
tokens.PopExpected(";");
return(new ContinueStatement(continueToken, owner));
}
private Annotation ParseAnnotation(TokenStream tokens)
{
Token annotationToken = tokens.PopExpected("@");
Token typeToken = tokens.Pop();
// TODO: refactor this. All built-in annotations should be exempt from the VerifyIdentifier check in an extensible way.
if (typeToken.Value != this.parser.Keywords.PRIVATE)
{
parser.VerifyIdentifier(typeToken);
}
Annotation annotation = new Annotation(annotationToken, typeToken);
List <Expression> args = new List <Expression>();
if (tokens.PopIfPresent("("))
{
while (!tokens.PopIfPresent(")"))
{
if (args.Count > 0)
{
tokens.PopExpected(",");
}
args.Add(this.parser.ExpressionParser.Parse(tokens, annotation));
}
}
annotation.SetArgs(args);
return(annotation);
}
protected ForLoopComponents ParseForLoopComponents(TokenStream tokens, Node owner)
{
List <Executable> init = new List <Executable>();
while (!tokens.PopIfPresent(";"))
{
if (init.Count > 0)
{
tokens.PopExpected(",");
}
init.Add(this.Parse(tokens, true, false, owner));
}
Expression condition = null;
if (!tokens.PopIfPresent(";"))
{
condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(";");
}
List <Executable> step = new List <Executable>();
while (!tokens.PopIfPresent(")"))
{
if (step.Count > 0)
{
tokens.PopExpected(",");
}
step.Add(this.Parse(tokens, true, false, owner));
}
return(new ForLoopComponents()
{
Init = init, Condition = condition, Step = step
});
}
protected Executable ParseFor(TokenStream tokens, Node owner)
{
Token forToken = tokens.PopExpected(this.parser.Keywords.FOR);
tokens.PopExpected("(");
tokens.EnsureNotEof();
if (this.IsForEachLoopParenthesisContents(tokens))
{
Pair <AType, Token> iteratorVariable = this.ParseForEachLoopIteratorVariable(tokens, owner);
AType iteratorVariableType = iteratorVariable.First;
Token iteratorToken = iteratorVariable.Second;
tokens.PopExpected(":");
Expression iterationExpression = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
IList <Executable> body = this.ParseBlock(tokens, false, owner);
return(new ForEachLoop(forToken, iteratorVariableType, iteratorVariable.Second, iterationExpression, body, owner));
}
else
{
ForLoopComponents parts = this.ParseForLoopComponents(tokens, owner);
IList <Executable> body = this.ParseBlock(tokens, false, owner);
return(new ForLoop(forToken, parts.Init, parts.Condition, parts.Step, body, owner));
}
}
private Executable ParseBreak(TokenStream tokens, TopLevelConstruct owner)
{
Token breakToken = tokens.PopExpected(this.parser.Keywords.BREAK);
tokens.PopExpected(";");
return(new BreakStatement(breakToken, owner));
}
private Executable ParseThrow(TokenStream tokens, TopLevelConstruct owner)
{
Token throwToken = tokens.PopExpected(this.parser.Keywords.THROW);
Expression throwExpression = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(";");
return(new ThrowStatement(throwToken, throwExpression, owner));
}
private FunctionDefinition ParseFunction(
TokenStream tokens,
TopLevelConstruct nullableOwner,
FileScope fileScope,
AnnotationCollection annotations)
{
bool isStatic =
nullableOwner != null &&
nullableOwner is ClassDefinition &&
tokens.PopIfPresent(this.parser.Keywords.STATIC);
Token functionToken = tokens.PopExpected(this.parser.Keywords.FUNCTION);
Token functionNameToken = tokens.Pop();
this.parser.VerifyIdentifier(functionNameToken);
FunctionDefinition fd = new FunctionDefinition(functionToken, parser.CurrentLibrary, nullableOwner, isStatic, functionNameToken, annotations, fileScope);
tokens.PopExpected("(");
List <Token> argNames = new List <Token>();
List <Expression> defaultValues = new List <Expression>();
bool optionalArgFound = false;
while (!tokens.PopIfPresent(")"))
{
if (argNames.Count > 0)
{
tokens.PopExpected(",");
}
Token argName = tokens.Pop();
Expression defaultValue = null;
this.parser.VerifyIdentifier(argName);
if (tokens.PopIfPresent("="))
{
optionalArgFound = true;
defaultValue = this.parser.ExpressionParser.Parse(tokens, fd);
}
else if (optionalArgFound)
{
throw new ParserException(argName, "All optional arguments must come at the end of the argument list.");
}
argNames.Add(argName);
defaultValues.Add(defaultValue);
}
IList <Executable> code = ParserContext.ParseBlock(parser, tokens, true, fd);
fd.ArgNames = argNames.ToArray();
fd.DefaultValues = defaultValues.ToArray();
fd.Code = code.ToArray();
return(fd);
}
protected virtual Namespace ParseNamespace(
TokenStream tokens,
Node owner,
FileScope fileScope,
AnnotationCollection annotations)
{
Token namespaceToken = tokens.PopExpected(this.parser.Keywords.NAMESPACE);
Token first = tokens.Pop();
this.parser.VerifyIdentifier(first);
List <Token> namespacePieces = new List <Token>()
{
first
};
string namespaceBuilder = first.Value;
parser.RegisterNamespace(namespaceBuilder);
while (tokens.PopIfPresent("."))
{
Token nsToken = tokens.Pop();
this.parser.VerifyIdentifier(nsToken);
namespacePieces.Add(nsToken);
namespaceBuilder += "." + nsToken.Value;
parser.RegisterNamespace(namespaceBuilder);
}
string name = string.Join(".", namespacePieces.Select <Token, string>(t => t.Value));
Namespace namespaceInstance = new Namespace(namespaceToken, name, owner, fileScope, ModifierCollection.EMPTY, annotations);
tokens.PopExpected("{");
List <TopLevelEntity> namespaceMembers = new List <TopLevelEntity>();
while (!tokens.PopIfPresent("}"))
{
TopLevelEntity executable = this.Parse(tokens, namespaceInstance, fileScope);
if (executable is FunctionDefinition ||
executable is ClassDefinition ||
executable is EnumDefinition ||
executable is ConstDefinition ||
executable is Namespace)
{
namespaceMembers.Add(executable);
}
else
{
throw new ParserException(executable, "Only function, class, and nested namespace declarations may exist as direct members of a namespace.");
}
}
namespaceInstance.Code = namespaceMembers.ToArray();
return(namespaceInstance);
}
private Executable ParseWhile(TokenStream tokens, TopLevelConstruct owner)
{
Token whileToken = tokens.PopExpected(this.parser.Keywords.WHILE);
tokens.PopExpected("(");
Expression condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
IList <Executable> body = ParserContext.ParseBlock(parser, tokens, false, owner);
return(new WhileLoop(whileToken, condition, body, owner));
}
private ConstStatement ParseConst(TokenStream tokens, TopLevelConstruct owner, FileScope fileScope, AnnotationCollection annotations)
{
Token constToken = tokens.PopExpected(this.parser.Keywords.CONST);
Token nameToken = tokens.Pop();
ConstStatement constStatement = new ConstStatement(constToken, nameToken, owner, parser.CurrentLibrary, fileScope, annotations);
this.parser.VerifyIdentifier(nameToken);
tokens.PopExpected("=");
constStatement.Expression = this.parser.ExpressionParser.Parse(tokens, constStatement);
tokens.PopExpected(";");
return(constStatement);
}
private Executable ParseReturn(TokenStream tokens, TopLevelConstruct owner)
{
Token returnToken = tokens.PopExpected(this.parser.Keywords.RETURN);
Expression expr = null;
if (!tokens.PopIfPresent(";"))
{
expr = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(";");
}
return(new ReturnStatement(returnToken, expr, owner));
}
private Executable ParseDoWhile(TokenStream tokens, TopLevelConstruct owner)
{
Token doToken = tokens.PopExpected(this.parser.Keywords.DO);
IList <Executable> body = ParserContext.ParseBlock(parser, tokens, true, owner);
tokens.PopExpected(this.parser.Keywords.DO_WHILE_END);
tokens.PopExpected("(");
Expression condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
tokens.PopExpected(";");
return(new DoWhileLoop(doToken, body, condition, owner));
}
protected IList <Expression> ParseArgumentList(TokenStream tokens, Node owner)
{
List <Expression> args = new List <Expression>();
tokens.PopExpected("(");
while (!tokens.PopIfPresent(")"))
{
if (args.Count > 0)
{
tokens.PopExpected(",");
}
args.Add(Parse(tokens, owner));
}
return(args);
}
internal virtual IList <Executable> ParseBlock(TokenStream tokens, bool bracketsRequired, Node owner, bool semicolonRequired)
{
List <Executable> output = new List <Executable>();
if (tokens.PopIfPresent("{"))
{
while (!tokens.PopIfPresent("}"))
{
output.Add(this.parser.ExecutableParser.Parse(tokens, false, true, owner));
}
}
else
{
if (bracketsRequired)
{
tokens.PopExpected("{"); // throws with reasonable exception message.
}
if (tokens.PopIfPresent(";"))
{
return(output);
}
output.Add(this.parser.ExecutableParser.Parse(tokens, false, semicolonRequired, owner));
}
return(output);
}
private FieldDeclaration ParseField(TokenStream tokens, ClassDefinition owner, AnnotationCollection annotations)
{
bool isStatic = tokens.PopIfPresent(this.parser.Keywords.STATIC);
Token fieldToken = tokens.PopExpected(this.parser.Keywords.FIELD);
Token nameToken = tokens.Pop();
this.parser.VerifyIdentifier(nameToken);
FieldDeclaration fd = new FieldDeclaration(fieldToken, nameToken, owner, isStatic, annotations);
if (tokens.PopIfPresent("="))
{
fd.DefaultValue = this.parser.ExpressionParser.Parse(tokens, owner);
}
tokens.PopExpected(";");
return(fd);
}
private Expression ParseLambda(
TokenStream tokens,
Token firstToken,
IList <AType> argTypes,
IList <Token> args,
Node owner)
{
tokens.PopExpected("=>");
Lambda lambda = new Lambda(firstToken, owner, args, argTypes);
IList <Executable> lambdaCode;
if (tokens.IsNext("{"))
{
lambdaCode = this.parser.ExecutableParser.ParseBlock(tokens, false, lambda, false);
}
else
{
Expression lambdaBodyExpression = this.parser.ExpressionParser.ParseTernary(tokens, lambda);
lambdaCode = new Executable[] { new ExpressionAsExecutable(lambdaBodyExpression, lambda) };
}
if (lambdaCode.Count == 1 && lambdaCode[0] is ExpressionAsExecutable)
{
// If a lambda contains a single expression as its code body, then this is an implicit return statement.
ExpressionAsExecutable eae = (ExpressionAsExecutable)lambdaCode[0];
lambdaCode[0] = new ReturnStatement(eae.FirstToken, eae.Expression, lambda);
}
lambda.Code = lambdaCode.ToArray();
return(lambda);
}
internal static IList <Executable> ParseBlock(ParserContext parser, TokenStream tokens, bool bracketsRequired, TopLevelConstruct owner)
{
List <Executable> output = new List <Executable>();
if (tokens.PopIfPresent("{"))
{
while (!tokens.PopIfPresent("}"))
{
output.Add(parser.ExecutableParser.Parse(tokens, false, true, owner));
}
}
else
{
if (bracketsRequired)
{
tokens.PopExpected("{"); // throws with reasonable exception message.
}
if (tokens.PopIfPresent(";"))
{
return(output);
}
output.Add(parser.ExecutableParser.Parse(tokens, false, true, owner));
}
return(output);
}
protected virtual ConstructorDefinition ParseConstructor(
TokenStream tokens,
ClassDefinition owner,
ModifierCollection modifiers,
AnnotationCollection annotations)
{
Token constructorToken = tokens.PopExpected(this.parser.Keywords.CONSTRUCTOR);
ConstructorDefinition ctor = new ConstructorDefinition(constructorToken, modifiers, annotations, owner);
tokens.PopExpected("(");
List <AType> argTypes = new List <AType>();
List <Token> argNames = new List <Token>();
List <Expression> argValues = new List <Expression>();
this.ParseArgumentListDeclaration(tokens, ctor, argTypes, argNames, argValues);
List <Expression> baseArgs = new List <Expression>();
Token baseToken = null;
if (tokens.PopIfPresent(":"))
{
baseToken = tokens.PopExpected(this.parser.Keywords.BASE);
tokens.PopExpected("(");
while (!tokens.PopIfPresent(")"))
{
if (baseArgs.Count > 0)
{
tokens.PopExpected(",");
}
baseArgs.Add(this.parser.ExpressionParser.Parse(tokens, ctor));
}
}
IList <Executable> code = this.parser.ExecutableParser.ParseBlock(tokens, true, ctor);
ctor.SetArgs(argNames, argValues, argTypes);
ctor.SetBaseArgs(baseArgs);
ctor.SetCode(code);
ctor.BaseToken = baseToken;
return(ctor);
}
protected virtual EnumDefinition ParseEnumDefinition(
TokenStream tokens,
Node owner,
FileScope fileScope,
ModifierCollection modifiers,
AnnotationCollection annotations)
{
Token enumToken = tokens.PopExpected(this.parser.Keywords.ENUM);
Token nameToken = tokens.Pop();
this.parser.VerifyIdentifier(nameToken);
string name = nameToken.Value;
EnumDefinition ed = new EnumDefinition(enumToken, nameToken, owner, fileScope, modifiers, annotations);
tokens.PopExpected("{");
bool nextForbidden = false;
List <Token> items = new List <Token>();
List <Expression> values = new List <Expression>();
while (!tokens.PopIfPresent("}"))
{
if (nextForbidden)
{
tokens.PopExpected("}"); // crash
}
Token enumItem = tokens.Pop();
this.parser.VerifyIdentifier(enumItem);
if (tokens.PopIfPresent("="))
{
values.Add(this.parser.ExpressionParser.Parse(tokens, ed));
}
else
{
values.Add(null);
}
nextForbidden = !tokens.PopIfPresent(",");
items.Add(enumItem);
}
ed.SetItems(items, values);
return(ed);
}
private Expression ParseInstantiate(TokenStream tokens, TopLevelConstruct owner)
{
Token newToken = tokens.PopExpected(this.parser.Keywords.NEW);
Token classNameToken = tokens.Pop();
string name = this.parser.PopClassNameWithFirstTokenAlreadyPopped(tokens, classNameToken);
List <Expression> args = new List <Expression>();
tokens.PopExpected("(");
while (!tokens.PopIfPresent(")"))
{
if (args.Count > 0)
{
tokens.PopExpected(",");
}
args.Add(Parse(tokens, owner));
}
return(new Instantiate(newToken, classNameToken, name, args, owner));
}
private Executable ParseFor(TokenStream tokens, TopLevelConstruct owner)
{
Token forToken = tokens.PopExpected(this.parser.Keywords.FOR);
tokens.PopExpected("(");
if (!tokens.HasMore)
{
tokens.ThrowEofException();
}
if (this.parser.IsValidIdentifier(tokens.PeekValue()) && tokens.PeekValue(1) == ":")
{
Token iteratorToken = tokens.Pop();
if (this.parser.IsReservedKeyword(iteratorToken.Value))
{
throw new ParserException(iteratorToken, "Cannot use this name for an iterator.");
}
tokens.PopExpected(":");
Expression iterationExpression = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
IList <Executable> body = ParserContext.ParseBlock(parser, tokens, false, owner);
return(new ForEachLoop(forToken, iteratorToken, iterationExpression, body, owner));
}
else
{
List <Executable> init = new List <Executable>();
while (!tokens.PopIfPresent(";"))
{
if (init.Count > 0)
{
tokens.PopExpected(",");
}
init.Add(this.Parse(tokens, true, false, owner));
}
Expression condition = null;
if (!tokens.PopIfPresent(";"))
{
condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(";");
}
List <Executable> step = new List <Executable>();
while (!tokens.PopIfPresent(")"))
{
if (step.Count > 0)
{
tokens.PopExpected(",");
}
step.Add(this.Parse(tokens, true, false, owner));
}
IList <Executable> body = ParserContext.ParseBlock(parser, tokens, false, owner);
return(new ForLoop(forToken, init, condition, step, body, owner));
}
}
private ForEachLoop ParseForEachCSharp(TokenStream tokens, Node owner)
{
if (!this.parser.IsCSharpCompat)
{
throw new System.InvalidOperationException();
}
Token foreachToken = tokens.PopExpected("foreach");
tokens.PopExpected("(");
AType iteratorVariableType = this.parser.TypeParser.Parse(tokens);
Token iteratorVariable = tokens.PopWord();
tokens.PopExpected("in");
Expression listExpr = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
IList <Executable> body = this.ParseBlock(tokens, false, owner);
return(new ForEachLoop(foreachToken, iteratorVariableType, iteratorVariable, listExpr, body, owner));
}
private Executable ParseIf(TokenStream tokens, TopLevelConstruct owner)
{
Token ifToken = tokens.PopExpected(this.parser.Keywords.IF);
tokens.PopExpected("(");
Expression condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
IList <Executable> body = ParserContext.ParseBlock(parser, tokens, false, owner);
IList <Executable> elseBody;
if (tokens.PopIfPresent(this.parser.Keywords.ELSE))
{
elseBody = ParserContext.ParseBlock(parser, tokens, false, owner);
}
else
{
elseBody = new Executable[0];
}
return(new IfStatement(ifToken, condition, body, elseBody, owner));
}
private ConstructorDefinition ParseConstructor(
TokenStream tokens,
TopLevelConstruct owner,
AnnotationCollection annotations)
{
Token constructorToken = tokens.PopExpected(this.parser.Keywords.CONSTRUCTOR);
tokens.PopExpected("(");
List <Token> argNames = new List <Token>();
List <Expression> argValues = new List <Expression>();
bool optionalArgFound = false;
while (!tokens.PopIfPresent(")"))
{
if (argNames.Count > 0)
{
tokens.PopExpected(",");
}
Token argName = tokens.Pop();
this.parser.VerifyIdentifier(argName);
Expression defaultValue = null;
if (tokens.PopIfPresent("="))
{
defaultValue = this.parser.ExpressionParser.Parse(tokens, owner);
optionalArgFound = true;
}
else if (optionalArgFound)
{
throw this.parser.GenerateParseError(
ErrorMessages.OPTIONAL_ARGUMENT_WAS_NOT_AT_END_OF_ARGUMENT_LIST,
argName);
}
argNames.Add(argName);
argValues.Add(defaultValue);
}
List <Expression> baseArgs = new List <Expression>();
Token baseToken = null;
if (tokens.PopIfPresent(":"))
{
baseToken = tokens.PopExpected(this.parser.Keywords.BASE);
tokens.PopExpected("(");
while (!tokens.PopIfPresent(")"))
{
if (baseArgs.Count > 0)
{
tokens.PopExpected(",");
}
baseArgs.Add(this.parser.ExpressionParser.Parse(tokens, owner));
}
}
IList <Executable> code = ParserContext.ParseBlock(parser, tokens, true, owner);
return(new ConstructorDefinition(constructorToken, argNames, argValues, baseArgs, code, baseToken, annotations, owner));
}
internal virtual ImportStatement ParseImport(TokenStream tokens, FileScope fileScope)
{
Token importToken = this.parser.IsCSharpCompat
? tokens.PopExpected(parser.Keywords.IMPORT, "using")
: tokens.PopExpected(parser.Keywords.IMPORT);
List <string> importPathBuilder = new List <string>();
while (!tokens.PopIfPresent(";"))
{
if (importPathBuilder.Count > 0)
{
tokens.PopExpected(".");
}
Token pathToken = tokens.Pop();
parser.VerifyIdentifier(pathToken);
importPathBuilder.Add(pathToken.Value);
}
string importPath = string.Join(".", importPathBuilder);
return(new ImportStatement(importToken, importPath, fileScope));
}
private Expression ParseTernary(TokenStream tokens, Node owner)
{
Expression root = ParseNullCoalescing(tokens, owner);
if (tokens.PopIfPresent("?"))
{
Expression trueExpr = ParseTernary(tokens, owner);
tokens.PopExpected(":");
Expression falseExpr = ParseTernary(tokens, owner);
return(new Ternary(root, trueExpr, falseExpr, owner));
}
return(root);
}
protected void ParseArgumentListDeclaration(
TokenStream tokens,
Node owner,
IList <AType> argTypesOut,
IList <Token> argNamesOut,
IList <Expression> argDefaultValuesOut)
{
bool optionalArgFound = false;
while (!tokens.PopIfPresent(")"))
{
if (argNamesOut.Count > 0)
{
tokens.PopExpected(",");
}
AType argType = this.HasTypes
? this.parser.TypeParser.Parse(tokens)
: AType.Any(tokens.Peek());
Token argName = tokens.Pop();
this.parser.VerifyIdentifier(argName);
Expression defaultValue = null;
if (tokens.PopIfPresent("="))
{
defaultValue = this.parser.ExpressionParser.Parse(tokens, owner);
optionalArgFound = true;
}
else if (optionalArgFound)
{
throw this.parser.GenerateParseError(
ErrorMessages.OPTIONAL_ARGUMENT_WAS_NOT_AT_END_OF_ARGUMENT_LIST,
argName);
}
argTypesOut.Add(argType);
argNamesOut.Add(argName);
argDefaultValuesOut.Add(defaultValue);
}
}
protected virtual ClassDefinition ParseClassDefinition(
TokenStream tokens,
Node owner,
FileScope fileScope,
ModifierCollection modifiers,
AnnotationCollection classAnnotations)
{
Token classToken = tokens.PopExpected(this.parser.Keywords.CLASS);
Token classNameToken = tokens.Pop();
if (classNameToken.Type != TokenType.WORD)
{
throw new ParserException(classNameToken, "This is not a valid class name.");
}
List <Token> baseClassTokens = new List <Token>();
List <string> baseClassStrings = new List <string>();
if (tokens.PopIfPresent(":"))
{
if (baseClassTokens.Count > 0)
{
tokens.PopExpected(",");
}
Token baseClassToken = tokens.Pop();
string baseClassName = baseClassToken.Value;
this.parser.VerifyIdentifier(baseClassToken);
while (tokens.PopIfPresent("."))
{
Token baseClassTokenNext = tokens.Pop();
this.parser.VerifyIdentifier(baseClassTokenNext);
baseClassName += "." + baseClassTokenNext.Value;
}
baseClassTokens.Add(baseClassToken);
baseClassStrings.Add(baseClassName);
}
ClassDefinition cd = new ClassDefinition(
classToken,
classNameToken,
baseClassTokens,
baseClassStrings,
owner,
fileScope,
modifiers,
classAnnotations);
tokens.PopExpected("{");
List <FunctionDefinition> methods = new List <FunctionDefinition>();
List <FieldDefinition> fields = new List <FieldDefinition>();
List <PropertyDefinition> properties = new List <PropertyDefinition>();
while (!tokens.PopIfPresent("}"))
{
this.ParseClassMember(tokens, fileScope, cd, methods, fields, properties);
}
cd.Methods = methods.ToArray();
cd.Fields = fields.ToArray();
if (cd.Constructor == null)
{
// This should be empty if there is no base class, or just pass along the base class' args if there is.
cd.Constructor = new ConstructorDefinition(
cd,
ModifierCollection.EMPTY,
new AnnotationCollection(parser));
if (cd.BaseClassTokens.Length > 0)
{
cd.Constructor.BaseToken = cd.FirstToken;
cd.Constructor.SetBaseArgs(new Expression[0]);
}
}
return(cd);
}
private Executable ParseSwitch(TokenStream tokens, TopLevelConstruct owner)
{
Token switchToken = tokens.PopExpected(this.parser.Keywords.SWITCH);
Expression explicitMax = null;
Token explicitMaxToken = null;
if (tokens.IsNext("{"))
{
explicitMaxToken = tokens.Pop();
explicitMax = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected("}");
}
tokens.PopExpected("(");
Expression condition = this.parser.ExpressionParser.Parse(tokens, owner);
tokens.PopExpected(")");
tokens.PopExpected("{");
List <List <Expression> > cases = new List <List <Expression> >();
List <Token> firstTokens = new List <Token>();
List <List <Executable> > code = new List <List <Executable> >();
char state = '?'; // ? - first, O - code, A - case
bool defaultEncountered = false;
while (!tokens.PopIfPresent("}"))
{
if (tokens.IsNext(this.parser.Keywords.CASE))
{
if (defaultEncountered)
{
throw new ParserException(tokens.Peek(), "default condition in a switch statement must be the last condition.");
}
Token caseToken = tokens.PopExpected(this.parser.Keywords.CASE);
if (state != 'A')
{
cases.Add(new List <Expression>());
firstTokens.Add(caseToken);
code.Add(null);
state = 'A';
}
cases[cases.Count - 1].Add(this.parser.ExpressionParser.Parse(tokens, owner));
tokens.PopExpected(":");
}
else if (tokens.IsNext(this.parser.Keywords.DEFAULT))
{
Token defaultToken = tokens.PopExpected(this.parser.Keywords.DEFAULT);
if (state != 'A')
{
cases.Add(new List <Expression>());
firstTokens.Add(defaultToken);
code.Add(null);
state = 'A';
}
cases[cases.Count - 1].Add(null);
tokens.PopExpected(":");
defaultEncountered = true;
}
else
{
if (state != 'O')
{
cases.Add(null);
firstTokens.Add(null);
code.Add(new List <Executable>());
state = 'O';
}
code[code.Count - 1].Add(this.parser.ExecutableParser.Parse(tokens, false, true, owner));
}
}
return(new SwitchStatement(switchToken, condition, firstTokens, cases, code, explicitMax, explicitMaxToken, owner));
}
private Executable ParseTry(TokenStream tokens, TopLevelConstruct owner)
{
Token tryToken = tokens.PopExpected(this.parser.Keywords.TRY);
IList <Executable> tryBlock = ParserContext.ParseBlock(parser, tokens, true, owner);
List <Token> catchTokens = new List <Token>();
List <string[]> exceptionTypes = new List <string[]>();
List <Token[]> exceptionTypeTokens = new List <Token[]>();
List <Token> exceptionVariables = new List <Token>();
List <Executable[]> catchBlocks = new List <Executable[]>();
Token finallyToken = null;
IList <Executable> finallyBlock = null;
while (tokens.IsNext(this.parser.Keywords.CATCH))
{
/*
* Parse patterns:
* All exceptions:
* 1a: catch { ... }
* 1b: catch (e) { ... }
*
* A certain exception:
* 2a: catch (ExceptionName) { ... }
* 2b: catch (ExceptionName e) { ... }
*
* Certain exceptions:
* 3a: catch (ExceptionName1 | ExceptionName2) { ... }
* 3b: catch (ExceptionName1 | ExceptionName2 e) { ... }
*
* Non-Context-Free alert:
* Note that if the exception variable does not contain a '.' character, 1b and 2a are
* ambiguous at parse time. Treat them both as 1b and then if the classname resolution
* fails, treat this as a variable.
*
* This is actually kind of bad because a typo in the classname will not be known.
* e.g "catch (Excpetion) {" will compile as a variable called "Excpetion"
*
* End-user workarounds:
* - always use a variable name OR
* - always fully qualify exception types e.g. Core.Exception
* Long-term plan:
* - add warning support and emit warnings for:
* - unused variables
* - style-breaking uppercase variables.
*/
Token catchToken = tokens.PopExpected(this.parser.Keywords.CATCH);
List <string> classNames = new List <string>();
List <Token> classTokens = new List <Token>();
Token variableToken = null;
if (tokens.PopIfPresent("("))
{
// This first one might actually be a variable. Assume class for now and sort it out later.
// (and by "later" I mean the ResolveNames phase)
Token classFirstToken = tokens.Pop();
string className = this.parser.PopClassNameWithFirstTokenAlreadyPopped(tokens, classFirstToken);
classNames.Add(className);
classTokens.Add(classFirstToken);
while (tokens.PopIfPresent("|"))
{
classFirstToken = tokens.Pop();
className = this.parser.PopClassNameWithFirstTokenAlreadyPopped(tokens, classFirstToken);
classNames.Add(className);
classTokens.Add(classFirstToken);
}
if (!tokens.IsNext(")"))
{
variableToken = tokens.Pop();
this.parser.VerifyIdentifier(variableToken);
}
tokens.PopExpected(")");
}
else
{
classNames.Add(null);
classTokens.Add(null);
}
Executable[] catchBlockCode = ParserContext.ParseBlock(parser, tokens, true, owner).ToArray();
catchTokens.Add(catchToken);
exceptionTypes.Add(classNames.ToArray());
exceptionTypeTokens.Add(classTokens.ToArray());
exceptionVariables.Add(variableToken);
catchBlocks.Add(catchBlockCode);
}
if (tokens.IsNext(this.parser.Keywords.FINALLY))
{
finallyToken = tokens.Pop();
finallyBlock = ParserContext.ParseBlock(parser, tokens, true, owner);
}
return(new TryStatement(tryToken, tryBlock, catchTokens, exceptionVariables, exceptionTypeTokens, exceptionTypes, catchBlocks, finallyToken, finallyBlock, owner));
}