private static CsExpression parseExpressionIdentifierOrKeyword(TokenJar tok, ref int i)
{
var startIndex = tok[i].StartIndex;
if (tok[i].IsIdentifier("from") && tok[i + 1].Type == TokenType.Identifier)
{
var linq = new CsLinqExpression { StartIndex = startIndex };
parseLinqQueryExpression(linq, tok, ref i);
linq.EndIndex = tok[i - 1].EndIndex;
return linq;
}
if (tok[i].IsBuiltin("{"))
{
try
{
var exprs = parseArrayLiteral(tok, ref i);
return new CsArrayLiteralExpression { StartIndex = startIndex, EndIndex = tok[i - 1].EndIndex, Expressions = exprs };
}
catch (ParseException e)
{
if (e.IncompleteResult is List<CsExpression>)
throw new ParseException(e.Message, e.Index, new CsArrayLiteralExpression { StartIndex = startIndex, Expressions = (List<CsExpression>) e.IncompleteResult }, e);
throw;
}
}
if (tok[i].Type == TokenType.CharacterLiteral)
return new CsCharacterLiteralExpression { StartIndex = startIndex, EndIndex = tok[i].EndIndex, Literal = tok[i++].TokenStr[0] };
if (tok[i].Type == TokenType.StringLiteral)
return new CsStringLiteralExpression { StartIndex = startIndex, EndIndex = tok[i].EndIndex, Literal = tok[i++].TokenStr };
if (tok[i].Type == TokenType.NumberLiteral)
return new CsNumberLiteralExpression { StartIndex = startIndex, EndIndex = tok[i].EndIndex, Literal = tok[i++].TokenStr };
if (tok[i].IsBuiltin("true")) { i++; return new CsBooleanLiteralExpression { StartIndex = tok[i - 1].StartIndex, EndIndex = tok[i - 1].EndIndex, Literal = true }; }
if (tok[i].IsBuiltin("false")) { i++; return new CsBooleanLiteralExpression { StartIndex = tok[i - 1].StartIndex, EndIndex = tok[i - 1].EndIndex, Literal = false }; }
if (tok[i].IsBuiltin("null")) { i++; return new CsNullExpression { StartIndex = tok[i - 1].StartIndex, EndIndex = tok[i - 1].EndIndex }; }
if (tok[i].IsBuiltin("this")) { i++; return new CsThisExpression { StartIndex = tok[i - 1].StartIndex, EndIndex = tok[i - 1].EndIndex }; }
if (tok[i].IsBuiltin("base")) { i++; return new CsBaseExpression { StartIndex = tok[i - 1].StartIndex, EndIndex = tok[i - 1].EndIndex }; }
if (tok[i].IsBuiltin("typeof") || tok[i].IsBuiltin("default") || tok[i].IsBuiltin("sizeof"))
{
var typof = tok[i].IsBuiltin("typeof");
var expr = typof ? new CsTypeofExpression() : tok[i].IsBuiltin("default") ? (CsTypeOperatorExpression) new CsDefaultExpression() : new CsSizeofExpression();
expr.StartIndex = startIndex;
i++;
if (!tok[i].IsBuiltin("("))
throw new ParseException("'(' expected after 'typeof' or 'default'.", tok[i].StartIndex);
i++;
CsTypeName ty;
var tif = typeIdentifierFlags.AllowKeywords | typeIdentifierFlags.AllowNullablesAndPointers | typeIdentifierFlags.AllowArrays;
try { ty = parseTypeName(tok, ref i, typof ? tif | typeIdentifierFlags.AllowEmptyGenerics : tif).Item1; }
catch (ParseException e)
{
if (e.IncompleteResult is CsTypeName)
expr.Type = (CsTypeName) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, expr, e);
}
expr.Type = ty;
if (!tok[i].IsBuiltin(")"))
throw new ParseException("')' expected.", tok[i].StartIndex, expr);
expr.EndIndex = tok[i].EndIndex;
i++;
return expr;
}
if (tok[i].IsBuiltin("checked") || tok[i].IsBuiltin("unchecked"))
{
var expr = tok[i].IsBuiltin("checked") ? (CsCheckedUncheckedExpression) new CsCheckedExpression() : new CsUncheckedExpression();
expr.StartIndex = startIndex;
i++;
if (!tok[i].IsBuiltin("("))
throw new ParseException("'(' expected after 'checked' or 'unchecked'.", tok[i].StartIndex);
i++;
expr.Subexpression = parseExpression(tok, ref i);
if (!tok[i].IsBuiltin(")"))
throw new ParseException("')' expected.", tok[i].StartIndex, expr);
expr.EndIndex = tok[i].EndIndex;
i++;
return expr;
}
if (tok[i].IsBuiltin("new"))
{
i++;
if (tok[i].IsBuiltin("{"))
{
var anon = new CsNewAnonymousTypeExpression { StartIndex = startIndex };
try { anon.Initializers = parseArrayLiteral(tok, ref i); }
catch (ParseException e)
{
if (e.IncompleteResult is List<CsExpression>)
anon.Initializers = (List<CsExpression>) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, anon, e);
}
anon.EndIndex = tok[i - 1].EndIndex;
return anon;
}
else if (tok[i].IsBuiltin("[") && tok[i + 1].IsBuiltin("]"))
{
i += 2;
// Implicitly-typed array
if (!tok[i].IsBuiltin("{"))
throw new ParseException("'{' expected.", tok[i].StartIndex);
try
{
var items = parseArrayLiteral(tok, ref i);
return new CsNewImplicitlyTypedArrayExpression { StartIndex = startIndex, EndIndex = tok[i - 1].EndIndex, Items = items };
}
catch (ParseException e)
{
if (e.IncompleteResult is List<CsExpression>)
throw new ParseException(e.Message, e.Index, new CsNewImplicitlyTypedArrayExpression { StartIndex = startIndex, Items = (List<CsExpression>) e.IncompleteResult }, e);
throw;
}
}
else if (tok[i].Type != TokenType.Identifier && tok[i].Type != TokenType.Builtin)
throw new ParseException("'{', '[' or type expected.", tok[i].StartIndex);
else
{
var ty = parseTypeName(tok, ref i, typeIdentifierFlags.AllowKeywords | typeIdentifierFlags.AllowNullablesAndPointers | typeIdentifierFlags.AllowArrays | typeIdentifierFlags.Lenient).Item1;
if (tok[i].IsBuiltin("("))
{
// Constructor call with parameters
var constructor = new CsNewConstructorExpression { StartIndex = startIndex, Type = ty };
try
{
bool dummy;
constructor.Arguments = parseArgumentList(tok, ref i, out dummy);
if (tok[i].IsBuiltin("{"))
constructor.Initializers = parseArrayLiteral(tok, ref i);
}
catch (ParseException e)
{
if (e.IncompleteResult is List<CsArgument>)
constructor.Arguments = (List<CsArgument>) e.IncompleteResult;
else if (e.IncompleteResult is List<CsExpression>)
constructor.Initializers = (List<CsExpression>) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, constructor, e);
}
constructor.EndIndex = tok[i - 1].EndIndex;
return constructor;
}
else if (tok[i].IsBuiltin("{"))
{
// Constructor call without parameters
var constructor = new CsNewConstructorExpression { StartIndex = startIndex, Type = ty };
try { constructor.Initializers = parseArrayLiteral(tok, ref i); }
catch (ParseException e)
{
if (e.IncompleteResult is List<CsExpression>)
constructor.Initializers = (List<CsExpression>) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, constructor, e);
}
constructor.EndIndex = tok[i - 1].EndIndex;
return constructor;
}
else if (tok[i].IsBuiltin("["))
{
// Array construction
bool dummy;
var k = i;
var ret = new CsNewArrayExpression { StartIndex = startIndex, Type = ty };
ret.SizeExpressions.AddRange(parseArgumentList(tok, ref i, out dummy).Select(p =>
{
if (p.Mode != ArgumentMode.In)
throw new ParseException("'out' and 'ref' parameters are not allowed in an array constructor.", tok[k].StartIndex);
return p.Expression;
}));
while (tok[i].IsBuiltin("["))
{
i++;
int num = 1;
while (tok[i].IsBuiltin(","))
{
num++;
i++;
}
if (!tok[i].IsBuiltin("]"))
throw new ParseException("',' or ']' expected.", tok[i].StartIndex, ret);
i++;
ret.AdditionalRanks.Add(num);
}
if (tok[i].IsBuiltin("{"))
{
try { ret.Items = parseArrayLiteral(tok, ref i); }
catch (ParseException e)
{
if (e.IncompleteResult is List<CsExpression>)
ret.Items = (List<CsExpression>) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, ret, e);
}
}
ret.EndIndex = tok[i - 1].EndIndex;
return ret;
}
else
throw new ParseException("'(', '[' or '{' expected.", tok[i].StartIndex);
}
}
if (tok[i].IsBuiltin("delegate"))
{
i++;
var delegateParams = tok[i].IsBuiltin("(") ? parseParameterList(tok, ref i) : null;
var block = parseBlock(tok, ref i);
return new CsAnonymousMethodExpression { StartIndex = startIndex, EndIndex = tok[i - 1].EndIndex, Body = block, Parameters = delegateParams };
}
// See if this could be a lambda expression. If it is, set 'parameters' to something non-null and move 'i' to behind the '=>'. Otherwise, keep 'i' unchanged.
List<CsParameter> parameters = null;
if (tok[i].Type == TokenType.Identifier && tok[i + 1].IsBuiltin("=>"))
{
// p => ...
parameters = new List<CsParameter> { new CsParameter { StartIndex = startIndex, EndIndex = tok[i].EndIndex, Name = tok[i].TokenStr } };
i += 2;
}
else if (tok[i].IsBuiltin("("))
{
// () => ...
if (tok[i + 1].IsBuiltin(")") && tok[i + 2].IsBuiltin("=>"))
{
parameters = new List<CsParameter>();
i += 3;
}
else
{
// Try (Type p1, Type p2) => ...
try
{
var j = i;
var tried = parseParameterList(tok, ref j, tryNotToThrow: true);
if (tried != null && tok[j].IsBuiltin("=>"))
{
i = j + 1;
parameters = tried;
}
}
catch { }
}
// If (Type p1, Type p2) => ... still didn't work, try (p1, p2) => ...
if (parameters == null && tok[i + 1].Type == TokenType.Identifier)
{
var ps = new List<CsParameter> { new CsParameter { StartIndex = tok[i + 1].StartIndex, EndIndex = tok[i + 1].EndIndex, Name = tok[i + 1].TokenStr } };
var j = i + 2;
while (tok[j].IsBuiltin(",") && tok[j + 1].Type == TokenType.Identifier)
{
ps.Add(new CsParameter { StartIndex = tok[j + 1].StartIndex, EndIndex = tok[j + 1].EndIndex, Name = tok[j + 1].TokenStr });
j += 2;
}
if (tok[j].IsBuiltin(")") && tok[j + 1].IsBuiltin("=>"))
{
parameters = ps;
i = j + 2;
}
}
}
// If 'parameters' is non-null, we found a lambda expression and 'i' is pointing behind the '=>'.
if (parameters != null)
{
if (tok[i].IsBuiltin("{"))
{
var lambda = new CsBlockLambdaExpression { StartIndex = startIndex, Parameters = parameters };
try { lambda.Body = parseBlock(tok, ref i); }
catch (ParseException e)
{
if (e.IncompleteResult is CsBlock)
{
lambda.Body = (CsBlock) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, lambda, e);
}
throw;
}
lambda.EndIndex = lambda.Body.EndIndex;
return lambda;
}
else
{
var lambda = new CsSimpleLambdaExpression { StartIndex = startIndex, Parameters = parameters };
try { lambda.Body = parseExpression(tok, ref i); }
catch (ParseException e)
{
if (e.IncompleteResult is CsExpression)
{
lambda.Body = (CsExpression) e.IncompleteResult;
throw new ParseException(e.Message, e.Index, lambda, e);
}
throw;
}
lambda.EndIndex = lambda.Body.EndIndex;
return lambda;
}
}
// If we get to here, then there is an open-parenthesis that is not the beginning of a lambda expression parameter list.
if (tok[i].IsBuiltin("("))
{
i++;
// Every time we encounter an open-parenthesis, we don't know in advance whether it's a cast, a sub-expression, or a lambda expression.
// We've already checked for lambda expression above, so we can rule that one out, but to check whether it's a cast, we need to tentatively
// parse it, see if it is followed by ')', and then follow a heuristic specified in the C# standard.
CsTypeName typeName = null;
CsExpression expression = null;
int afterType = i;
int afterExpression = i;
// Does it parse as a type?
try
{
var result = parseTypeName(tok, ref afterType, typeIdentifierFlags.AllowKeywords | typeIdentifierFlags.AllowNullablesAndPointers | typeIdentifierFlags.AllowArrays, true);
if (result != null && tok[afterType].IsBuiltin(")"))
{
typeName = result.Item1;
afterType++;
}
}
catch { }
// Does it parse as a parenthesised expression?
try
{
expression = parseExpression(tok, ref afterExpression, true);
if (!tok[afterExpression].IsBuiltin(")"))
throw new ParseException("')' expected after parenthesised expression.", tok[afterExpression].StartIndex);
afterExpression++;
}
catch (ParseException)
{
// It’s neither an expression nor a valid type name.
if (typeName == null)
throw;
}
// According to the Standard, we are supposed to interpret this as a cast if:
// • it definitely doesn’t parse as an expression; OR
// • the next token is one of a special set
if (expression == null || (typeName != null && (
tok[afterType].IsBuiltin("~") || tok[afterType].IsBuiltin("!") || tok[afterType].IsBuiltin("(") ||
tok[afterType].Type == TokenType.Identifier || tok[afterType].Type == TokenType.CharacterLiteral ||
tok[afterType].Type == TokenType.NumberLiteral || tok[afterType].Type == TokenType.StringLiteral ||
(tok[afterType].Type == TokenType.Builtin && tok[afterType].TokenStr != "is" && tok[afterType].TokenStr != "as" && Lexer.Keywords.Contains(tok[afterType].TokenStr)))))
{
// It’s a cast!
try
{
i = afterType;
var operand = parseExpressionUnary(tok, ref i);
return new CsCastExpression { StartIndex = startIndex, EndIndex = operand.EndIndex, Operand = operand, Type = typeName };
}
catch (ParseException e)
{
if (e.IncompleteResult is CsExpression)
throw new ParseException(e.Message, e.Index, new CsCastExpression { StartIndex = startIndex, Operand = (CsExpression) e.IncompleteResult, Type = typeName }, e);
throw;
}
}
// It’s a subexpression!
i = afterExpression;
return new CsParenthesizedExpression { StartIndex = startIndex, EndIndex = tok[i - 1].EndIndex, Subexpression = expression };
}
var simpleName = parseExpressionIdentifier(tok, ref i);
return new CsIdentifierExpression { StartIndex = startIndex, EndIndex = tok[i - 1].EndIndex, Identifier = simpleName };
}
private static void parseLinqQueryContinuation(CsLinqExpression linq, TokenJar tok, ref int i)
{
tok[i].Assert("into");
var startIndex = tok[i].StartIndex;
i++;
linq.Elements.Add(new CsLinqIntoClause { StartIndex = startIndex, EndIndex = tok[i].EndIndex, ItemName = tok[i].Identifier() });
i++;
parseLinqQueryBody(linq, tok, ref i);
}
private static void parseLinqQueryExpression(CsLinqExpression linq, TokenJar tok, ref int i)
{
linq.Elements.Add(parseLinqFromClause(tok, ref i));
parseLinqQueryBody(linq, tok, ref i);
}
private static void parseLinqQueryBody(CsLinqExpression linq, TokenJar tok, ref int i)
{
while (tok[i].IsIdentifier("from") || tok[i].IsIdentifier("let") || tok[i].IsIdentifier("where") || tok[i].IsIdentifier("join") || tok[i].IsIdentifier("orderby"))
{
if (tok[i].IsIdentifier("from"))
linq.Elements.Add(parseLinqFromClause(tok, ref i));
else if (tok[i].IsIdentifier("let"))
linq.Elements.Add(parseLinqLetClause(tok, ref i));
else if (tok[i].IsIdentifier("where"))
linq.Elements.Add(parseLinqWhereClause(tok, ref i));
else if (tok[i].IsIdentifier("join"))
linq.Elements.Add(parseLinqJoinClause(tok, ref i));
else if (tok[i].IsIdentifier("orderby"))
linq.Elements.Add(parseLinqOrderByClause(tok, ref i));
}
if (tok[i].IsIdentifier("select"))
linq.Elements.Add(parseLinqSelectClause(tok, ref i));
else if (tok[i].IsIdentifier("group"))
linq.Elements.Add(parseLinqGroupByClause(tok, ref i));
else
throw new ParseException("'select' or 'group' expected.", tok[i].StartIndex);
if (tok[i].IsIdentifier("into"))
parseLinqQueryContinuation(linq, tok, ref i);
}