public static Expression GenerateConversion(Expression expr, Type type, int errorPos)
{
var exprType = expr.Type;
if (exprType == type)
{
return(expr);
}
//if (exprType.IsValueType && type.IsValueType)
//{
// if ((IsNullableType(exprType) || IsNullableType(type)) &&
// GetNonNullableType(exprType) == GetNonNullableType(type))
// return Expression.Convert(expr, type);
// if ((IsNumericType(exprType) || IsEnumType(exprType)) &&
// (IsNumericType(type)) || IsEnumType(type))
// return Expression.ConvertChecked(expr, type);
//}
//if (exprType.IsAssignableFrom(type) || type.IsAssignableFrom(exprType) ||
// exprType.IsInterface || type.IsInterface)
//{
// return Expression.Convert(expr, type);
//}
try
{
return(Expression.ConvertChecked(expr, type));
}
catch (InvalidOperationException)
{
throw ParseException.Create(errorPos, ErrorMessages.CannotConvertValue,
Types.GetTypeName(exprType), Types.GetTypeName(type));
}
}
private Expression ParsePrimaryStart()
{
switch (_token.id)
{
case TokenId.Identifier:
return(ParseIdentifier());
case TokenId.CharLiteral:
return(ParseCharLiteral());
case TokenId.StringLiteral:
return(ParseStringLiteral());
case TokenId.IntegerLiteral:
return(ParseIntegerLiteral());
case TokenId.RealLiteral:
return(ParseRealLiteral());
case TokenId.OpenParen:
return(ParseParenExpression());
case TokenId.End:
return(Expression.Empty());
default:
throw ParseException.Create(_token.pos, ErrorMessages.ExpressionExpected);
}
}
private Expression ParseTypeKeyword(Type type)
{
var errorPos = _token.pos;
NextToken();
if (_token.id == TokenId.Question)
{
if (!type.IsValueType || Types.IsNullableType(type))
{
throw ParseException.Create(errorPos, ErrorMessages.TypeHasNoNullableForm, Types.GetTypeName(type));
}
type = typeof(Nullable <>).MakeGenericType(type);
NextToken();
}
//if (token.id == TokenId.OpenParen)
//{
// return ParseTypeConstructor(type, errorPos);
//}
if (_token.id == TokenId.CloseParen)
{
return(Expression.Constant(type));
}
ValidateToken(TokenId.Dot, ErrorMessages.DotOrOpenParenExpected);
NextToken();
return(ParseMemberAccess(type, null));
}
private Expression ParseExtensionMethodInvocation(Type type, Expression instance, int errorPos, string id, Expression[] args)
{
var extensionMethodsArguments = new Expression[args.Length + 1];
extensionMethodsArguments[0] = instance;
args.CopyTo(extensionMethodsArguments, 1);
var matchMethods = _arguments.GetExtensionMethods(id);
var extensionMethods = Expressions.FindBestMethod(matchMethods, extensionMethodsArguments);
if (extensionMethods.Length > 1)
{
throw ParseException.Create(errorPos, ErrorMessages.AmbiguousMethodInvocation, id, Types.GetTypeName(type));
}
if (extensionMethods.Length == 1)
{
var method = extensionMethods[0];
extensionMethodsArguments = method.PromotedParameters;
return(Expression.Call((MethodInfo)method.MethodBase, extensionMethodsArguments));
}
return(null);
}
// ReSharper disable once UnusedParameter.Local
private void ValidateToken(TokenId t)
{
if (_token.id != t)
{
throw ParseException.Create(_token.pos, ErrorMessages.SyntaxError);
}
}
// = operator
private Expression ParseAssignment()
{
var left = ParseConditional();
if (_token.id == TokenId.Equal)
{
if (!_arguments.Settings.AssignmentOperators.HasFlag(AssignmentOperators.AssignmentEqual))
{
throw new AssignmentOperatorDisabledException("=", _token.pos);
}
if (!Expressions.IsWritable(left))
{
throw ParseException.Create(_token.pos, ErrorMessages.ExpressionMustBeWritable);
}
NextToken();
var right = ParseAssignment();
var promoted = Expressions.PromoteExpression(right, left.Type, true);
if (promoted == null)
{
throw ParseException.Create(_token.pos, ErrorMessages.CannotConvertValue,
Types.GetTypeName(right.Type), Types.GetTypeName(left.Type));
}
left = Expression.Assign(left, promoted);
}
return(left);
}
// ReSharper disable once UnusedParameter.Local
private void ValidateToken(TokenId t, string errorMessage)
{
if (_token.id != t)
{
throw ParseException.Create(_token.pos, errorMessage);
}
}
private void ValidateDigit()
{
if (!char.IsDigit(_parseChar))
{
throw ParseException.Create(_parsePosition, ErrorMessages.DigitExpected);
}
}
public static Expression GenerateConditional(Expression test, Expression expr1, Expression expr2, int errorPos)
{
if (test.Type != typeof(bool))
{
throw ParseException.Create(errorPos, ErrorMessages.FirstExprMustBeBool);
}
if (expr1.Type != expr2.Type)
{
var expr1As2 = expr2 != ParserConstants.NullLiteralExpression ? PromoteExpression(expr1, expr2.Type, true) : null;
var expr2As1 = expr1 != ParserConstants.NullLiteralExpression ? PromoteExpression(expr2, expr1.Type, true) : null;
if (expr1As2 != null && expr2As1 == null)
{
expr1 = expr1As2;
}
else if (expr2As1 != null && expr1As2 == null)
{
expr2 = expr2As1;
}
else
{
var type1 = expr1 != ParserConstants.NullLiteralExpression ? expr1.Type.Name : "null";
var type2 = expr2 != ParserConstants.NullLiteralExpression ? expr2.Type.Name : "null";
if (expr1As2 != null)
{
throw ParseException.Create(errorPos, ErrorMessages.BothTypesConvertToOther, type1, type2);
}
throw ParseException.Create(errorPos, ErrorMessages.NeitherTypeConvertsToOther, type1, type2);
}
}
return(Expression.Condition(test, expr1, expr2));
}
private Expression ParseDelegateInvocation(Expression delegateExp, int errorPos)
{
var args = ParseArgumentList();
if (!_expressions.PrepareDelegateInvoke(delegateExp.Type, ref args))
{
throw ParseException.Create(errorPos, ErrorMessages.ArgsIncompatibleWithDelegate);
}
return(Expression.Invoke(delegateExp, args));
}
private Expression ParseCharLiteral()
{
ValidateToken(TokenId.CharLiteral);
var s = _token.text.Substring(1, _token.text.Length - 2);
s = EvalEscapeStringLiteral(s);
if (s.Length != 1)
{
throw ParseException.Create(_token.pos, ErrorMessages.InvalidCharacterLiteral);
}
NextToken();
return(Expressions.CreateLiteral(s[0]));
}
private Expression ParseElementAccess(Expression expr)
{
var errorPos = _token.pos;
ValidateToken(TokenId.OpenBracket, ErrorMessages.OpenParenExpected);
NextToken();
var args = ParseArguments();
ValidateToken(TokenId.CloseBracket, ErrorMessages.CloseBracketOrCommaExpected);
NextToken();
if (expr.Type.IsArray)
{
if (expr.Type.GetArrayRank() != args.Length)
{
throw ParseException.Create(errorPos, ErrorMessages.IncorrectNumberOfIndexes);
}
for (int i = 0; i < args.Length; i++)
{
args[i] = Expressions.PromoteExpression(args[i], typeof(int), true);
if (args[i] == null)
{
throw ParseException.Create(errorPos, ErrorMessages.InvalidIndex);
}
}
return(Expression.ArrayAccess(expr, args));
}
var applicableMethods = Expressions.FindIndexer(expr.Type, args);
if (applicableMethods.Length == 0)
{
throw ParseException.Create(errorPos, ErrorMessages.NoApplicableIndexer,
Types.GetTypeName(expr.Type));
}
if (applicableMethods.Length > 1)
{
throw ParseException.Create(errorPos, ErrorMessages.AmbiguousIndexerInvocation,
Types.GetTypeName(expr.Type));
}
var indexer = (Expressions.IndexerData)applicableMethods[0];
return(Expression.Property(expr, indexer.Indexer, indexer.PromotedParameters));
}
private Expression ParseIntegerLiteral()
{
ValidateToken(TokenId.IntegerLiteral);
var text = _token.text;
if (text[0] != '-')
{
if (!ulong.TryParse(text, ParseLiteralUnsignedNumberStyle, ParseCulture, out ulong value))
{
throw ParseException.Create(_token.pos, ErrorMessages.InvalidIntegerLiteral, text);
}
NextToken();
if (value <= int.MaxValue)
{
return(Expressions.CreateLiteral((int)value));
}
if (value <= uint.MaxValue)
{
return(Expressions.CreateLiteral((uint)value));
}
if (value <= long.MaxValue)
{
return(Expressions.CreateLiteral((long)value));
}
return(Expressions.CreateLiteral(value));
}
else
{
if (!long.TryParse(text, ParseLiteralNumberStyle, ParseCulture, out long value))
{
throw ParseException.Create(_token.pos, ErrorMessages.InvalidIntegerLiteral, text);
}
NextToken();
if (value >= int.MinValue && value <= int.MaxValue)
{
return(Expressions.CreateLiteral((int)value));
}
return(Expressions.CreateLiteral(value));
}
}
private Expression ParsePrimary()
{
var tokenPos = _token.pos;
var expr = ParsePrimaryStart();
while (true)
{
if (_token.id == TokenId.Dot)
{
NextToken();
expr = ParseMemberAccess(null, expr);
}
else if (_token.id == TokenId.QuestionDot)
{
NextToken();
expr = Expressions.GenerateConditional(Expressions.GenerateEqual(expr, ParserConstants.NullLiteralExpression), ParserConstants.NullLiteralExpression, ParseMemberAccess(null, expr), _token.pos);
}
else if (_token.id == TokenId.OpenBracket)
{
expr = ParseElementAccess(expr);
}
else if (_token.id == TokenId.OpenParen)
{
var lambda = expr as LambdaExpression;
if (lambda != null)
{
return(ParseLambdaInvocation(lambda, tokenPos));
}
if (typeof(Delegate).IsAssignableFrom(expr.Type))
{
expr = ParseDelegateInvocation(expr, tokenPos);
}
else
{
throw ParseException.Create(tokenPos, ErrorMessages.InvalidMethodCall, Types.GetTypeName(expr.Type));
}
}
else
{
break;
}
}
return(expr);
}
public Expression GeneratePropertyOrFieldExpression(Type type, Expression instance, int errorPos, string propertyOrFieldName)
{
var member = FindPropertyOrField(type, propertyOrFieldName, instance == null);
if (member != null)
{
return(member is PropertyInfo?
Expression.Property(instance, (PropertyInfo)member) :
Expression.Field(instance, (FieldInfo)member));
}
if (Types.IsDynamicType(type) || Expressions.IsDynamicExpression(instance))
{
return(Expressions.GenerateDynamicProperty(type, instance, propertyOrFieldName));
}
throw ParseException.Create(errorPos, ErrorMessages.UnknownPropertyOrField, propertyOrFieldName, Types.GetTypeName(type));
}
private Expression ParseNormalMethodInvocation(Type type, Expression instance, int errorPos, string id, Expression[] args)
{
var applicableMethods = _expressions.FindMethods(type, id, instance == null, args);
if (applicableMethods.Length > 1)
{
throw ParseException.Create(errorPos, ErrorMessages.AmbiguousMethodInvocation, id, Types.GetTypeName(type));
}
if (applicableMethods.Length == 1)
{
var method = applicableMethods[0];
return(Expression.Call(instance, (MethodInfo)method.MethodBase, method.PromotedParameters));
}
return(null);
}
private char EvalEscapeChar(char source)
{
switch (source)
{
case '\'':
return('\'');
case '"':
return('"');
case '\\':
return('\\');
case '0':
return('\0');
case 'a':
return('\a');
case 'b':
return('\b');
case 'f':
return('\f');
case 'n':
return('\n');
case 'r':
return('\r');
case 't':
return('\t');
case 'v':
return('\v');
default:
throw ParseException.Create(_token.pos, ErrorMessages.InvalidEscapeSequence);
}
}
// Working context implementation
//Expression ParseIt()
//{
// if (it == null)
// throw ParseError(ErrorMessages.NoItInScope);
// NextToken();
// return it;
//}
//Expression ParseIif()
//{
// int errorPos = token.pos;
// NextToken();
// Expression[] args = ParseArgumentList();
// if (args.Length != 3)
// throw ParseError(errorPos, ErrorMessages.IifRequiresThreeArgs);
// return GenerateConditional(args[0], args[1], args[2], errorPos);
//}
private Expression ParseTypeof()
{
var errorPos = _token.pos;
NextToken();
var args = ParseArgumentList();
if (args.Length != 1)
{
throw ParseException.Create(errorPos, ErrorMessages.TypeofRequiresOneArg);
}
var constExp = args[0] as ConstantExpression;
if (constExp == null || !(constExp.Value is Type))
{
throw ParseException.Create(errorPos, ErrorMessages.TypeofRequiresAType);
}
return(constExp);
}
private Expression ParseRealLiteral()
{
ValidateToken(TokenId.RealLiteral);
var text = _token.text;
object value = null;
var last = text[text.Length - 1];
if (last == 'F' || last == 'f')
{
if (float.TryParse(text.Substring(0, text.Length - 1), ParseLiteralDecimalNumberStyle, ParseCulture, out float f))
{
value = f;
}
}
else if (last == 'M' || last == 'm')
{
if (decimal.TryParse(text.Substring(0, text.Length - 1), ParseLiteralDecimalNumberStyle, ParseCulture, out decimal dc))
{
value = dc;
}
}
else
{
if (double.TryParse(text, ParseLiteralDecimalNumberStyle, ParseCulture, out double d))
{
value = d;
}
}
if (value == null)
{
throw ParseException.Create(_token.pos, ErrorMessages.InvalidRealLiteral, text);
}
NextToken();
return(Expressions.CreateLiteral(value));
}
// is, as operators
private Expression ParseTypeTesting()
{
var left = ParseAdditive();
while (_token.text == ParserConstants.KeywordIs ||
_token.text == ParserConstants.KeywordAs)
{
var typeOperator = _token.text;
var op = _token;
NextToken();
Type knownType;
if (!_arguments.TryGetKnownType(_token.text, out knownType))
{
throw ParseException.Create(op.pos, ErrorMessages.TypeIdentifierExpected);
}
if (typeOperator == ParserConstants.KeywordIs)
{
left = Expression.TypeIs(left, knownType);
}
else if (typeOperator == ParserConstants.KeywordAs)
{
left = Expression.TypeAs(left, knownType);
}
else
{
throw ParseException.Create(_token.pos, ErrorMessages.SyntaxError);
}
NextToken();
}
return(left);
}
private Expression ParseNew()
{
NextToken();
ValidateToken(TokenId.Identifier, ErrorMessages.IdentifierExpected);
Type newType;
if (!_arguments.TryGetKnownType(_token.text, out newType))
{
throw new UnknownIdentifierException(_token.text, _token.pos);
}
NextToken();
var args = ParseArgumentList();
var constructor = newType.GetConstructor(args.Select(p => p.Type).ToArray());
if (constructor == null)
{
throw ParseException.Create(_token.pos, ErrorMessages.NoApplicableConstructor, newType);
}
return(Expression.MemberInit(Expression.New(constructor, args)));
}
private string EvalEscapeStringLiteral(string source)
{
var builder = new StringBuilder();
for (int i = 0; i < source.Length; i++)
{
var c = source[i];
if (c == '\\')
{
if ((i + 1) == source.Length)
{
throw ParseException.Create(_token.pos, ErrorMessages.InvalidEscapeSequence);
}
builder.Append(EvalEscapeChar(source[++i]));
}
else
{
builder.Append(c);
}
}
return(builder.ToString());
}
public void RaiseParseError()
{
throw ParseException.Create(str, pos);
}
private void NextToken()
{
while (char.IsWhiteSpace(_parseChar))
{
NextChar();
}
TokenId t;
var tokenPos = _parsePosition;
switch (_parseChar)
{
case '!':
NextChar();
if (_parseChar == '=')
{
NextChar();
t = TokenId.ExclamationEqual;
}
else
{
t = TokenId.Exclamation;
}
break;
case '%':
NextChar();
t = TokenId.Percent;
break;
case '&':
NextChar();
if (_parseChar == '&')
{
NextChar();
t = TokenId.DoubleAmphersand;
}
else
{
t = TokenId.Amphersand;
}
break;
case '(':
NextChar();
t = TokenId.OpenParen;
break;
case ')':
NextChar();
t = TokenId.CloseParen;
break;
case '*':
NextChar();
t = TokenId.Asterisk;
break;
case '+':
NextChar();
t = TokenId.Plus;
break;
case ',':
NextChar();
t = TokenId.Comma;
break;
case '-':
NextChar();
t = TokenId.Minus;
break;
case '.':
NextChar();
if (char.IsDigit(_parseChar))
{
t = TokenId.RealLiteral;
do
{
NextChar();
} while (char.IsDigit(_parseChar));
if (_parseChar == 'E' || _parseChar == 'e')
{
t = TokenId.RealLiteral;
NextChar();
if (_parseChar == '+' || _parseChar == '-')
{
NextChar();
}
ValidateDigit();
do
{
NextChar();
} while (char.IsDigit(_parseChar));
}
if (_parseChar == 'F' || _parseChar == 'f' || _parseChar == 'M' || _parseChar == 'm')
{
NextChar();
}
break;
}
t = TokenId.Dot;
break;
case '/':
NextChar();
t = TokenId.Slash;
break;
case ':':
NextChar();
t = TokenId.Colon;
break;
case '<':
NextChar();
if (_parseChar == '=')
{
NextChar();
t = TokenId.LessThanEqual;
}
else
{
t = TokenId.LessThan;
}
break;
case '=':
NextChar();
if (_parseChar == '=')
{
NextChar();
t = TokenId.DoubleEqual;
}
else
{
t = TokenId.Equal;
}
break;
case '>':
NextChar();
if (_parseChar == '=')
{
NextChar();
t = TokenId.GreaterThanEqual;
}
else
{
t = TokenId.GreaterThan;
}
break;
case '?':
NextChar();
if (_parseChar == '.')
{
NextChar();
t = TokenId.QuestionDot;
}
else if (_parseChar == '?')
{
NextChar();
t = TokenId.QuestionQuestion;
}
else
{
t = TokenId.Question;
}
break;
case '[':
NextChar();
t = TokenId.OpenBracket;
break;
case ']':
NextChar();
t = TokenId.CloseBracket;
break;
case '|':
NextChar();
if (_parseChar == '|')
{
NextChar();
t = TokenId.DoubleBar;
}
else
{
t = TokenId.Bar;
}
break;
case '"':
NextChar();
bool isEscapeS = false;
bool isEndS = _parseChar == '\"';
while (_parsePosition < _expressionTextLength && !isEndS)
{
isEscapeS = _parseChar == '\\' && !isEscapeS;
NextChar();
isEndS = (_parseChar == '\"' && !isEscapeS);
}
if (_parsePosition == _expressionTextLength)
{
throw ParseException.Create(_parsePosition, ErrorMessages.UnterminatedStringLiteral);
}
NextChar();
t = TokenId.StringLiteral;
break;
case '\'':
NextChar();
bool isEscapeC = false;
bool isEndC = false;
while (_parsePosition < _expressionTextLength && !isEndC)
{
isEscapeC = _parseChar == '\\' && !isEscapeC;
NextChar();
isEndC = (_parseChar == '\'' && !isEscapeC);
}
if (_parsePosition == _expressionTextLength)
{
throw ParseException.Create(_parsePosition, ErrorMessages.UnterminatedStringLiteral);
}
NextChar();
t = TokenId.CharLiteral;
break;
case '^':
NextChar();
t = TokenId.Caret;
break;
default:
if (char.IsLetter(_parseChar) || _parseChar == '@' || _parseChar == '_')
{
do
{
NextChar();
} while (char.IsLetterOrDigit(_parseChar) || _parseChar == '_');
t = TokenId.Identifier;
break;
}
if (char.IsDigit(_parseChar))
{
t = TokenId.IntegerLiteral;
do
{
NextChar();
} while (char.IsDigit(_parseChar));
if (_parseChar == '.')
{
NextChar();
if (char.IsDigit(_parseChar))
{
t = TokenId.RealLiteral;
do
{
NextChar();
} while (char.IsDigit(_parseChar));
}
else
{
PreviousChar();
break;
}
}
if (_parseChar == 'E' || _parseChar == 'e')
{
t = TokenId.RealLiteral;
NextChar();
if (_parseChar == '+' || _parseChar == '-')
{
NextChar();
}
ValidateDigit();
do
{
NextChar();
} while (char.IsDigit(_parseChar));
}
if (_parseChar == 'F' || _parseChar == 'f' || _parseChar == 'M' || _parseChar == 'm')
{
t = TokenId.RealLiteral;
NextChar();
}
break;
}
if (_parsePosition == _expressionTextLength)
{
t = TokenId.End;
break;
}
throw ParseException.Create(_parsePosition, ErrorMessages.InvalidCharacter, _parseChar);
}
_token.id = t;
_token.text = _expressionText.Substring(tokenPos, _parsePosition - tokenPos);
_token.pos = tokenPos;
}
