/// <summary>
/// Совершает обход префиксного дерева токенов с помощью указанного лексера.
/// </summary>
/// <param name="lexer">Лексер исходного текста.</param>
/// <param name="start">Стартовый узел дерева.</param>
/// <returns>Последний узел и контейнер значений. Если обход закончен неудачно, контейнер значений будет являться <see langword="null"/>.</returns>
internal static (CommandTreeNode endNode, ValueContainer container) Traverse(ISourceLexer lexer, CommandTreeNode start)
{
var currentNode = start;
var stack = new Stack <int>();
var values = new List <object>();
var isSequenceRepeat = false;
while (true)
{
var token = lexer.NextSourceToken();
if (!currentNode.NextNodes.TryGetValue(token, out var reference))
{
break;
}
currentNode = reference.Node;
if (token.Type == TokenType.EndOfText)
{
return(currentNode, new ValueContainer(values.ToArray()));
}
if (reference.IsBack)
{
isSequenceRepeat = true;
}
var startCount = currentNode.InGroupStartCount;
if (isSequenceRepeat)
{
if (startCount > 0)
{
stack.Push(values.Count);
}
}
else
{
while (startCount > 0)
{
stack.Push(values.Count);
startCount--;
}
}
if (TokenFacts.IsPlaceholder(currentNode.TokenPrototype.Type))
{
values.Add(token);
}
if (currentNode.IsGroupEnd)
{
Debug.Assert(stack.Count > 0);
var index = stack.Pop();
var newContainerToken = ReduceToIterationContainer(values, index);
if (isSequenceRepeat)
{
var groupContainerToken = values[^ 1] as TokenWithValue <GroupContainer>;
IEnumerator <object[]> GetEnumerator()
{
foreach (var type in TokenFacts.GetAllTokenTypes())
{
foreach (var(exampleInput, exampleLiteral) in type.GetLiteralExamples())
{
yield return(new object[] { exampleInput, type, exampleLiteral });
}
}
}
private static Dictionary <Name, string> GetOperatorByName()
{
Dictionary <Name, string> dict = new Dictionary <Name, string>(28)
{
{ NameManager.GetPredefinedName(PredefinedName.PN_OPEQUALS), "equals" },
{ NameManager.GetPredefinedName(PredefinedName.PN_OPCOMPARE), "compare" }
};
foreach (OperatorInfo opInfo in s_operatorInfos)
{
PredefinedName predefName = opInfo.MethodName;
TokenKind token = opInfo.TokenKind;
if (predefName != PredefinedName.PN_COUNT && token != TokenKind.Unknown)
{
dict.Add(NameManager.GetPredefinedName(predefName), TokenFacts.GetText(token));
}
}
return(dict);
}
public static string GetDisplayName(OperatorKind op)
{
Debug.Assert(HasDisplayName(op));
return(TokenFacts.GetText(GetInfo(op).iToken));
}
private void ErrAppendType(CType pType, SubstContext pctx, bool fArgs)
{
if (pctx != null)
{
if (!pctx.FNop())
{
pType = GetTypeManager().SubstType(pType, pctx);
}
// We shouldn't use the SubstContext again so set it to NULL.
pctx = null;
}
switch (pType.GetTypeKind())
{
case TypeKind.TK_AggregateType:
{
AggregateType pAggType = pType.AsAggregateType();
// Check for a predefined class with a special "nice" name for
// error reported.
string text = PredefinedTypes.GetNiceName(pAggType.getAggregate());
if (text != null)
{
// Found a nice name.
ErrAppendString(text);
}
else if (pAggType.getAggregate().IsAnonymousType())
{
ErrAppendPrintf("AnonymousType#{0}", GetTypeID(pAggType));
break;
}
else
{
if (pAggType.outerType != null)
{
ErrAppendType(pAggType.outerType, pctx);
ErrAppendChar('.');
}
else
{
// In a namespace.
ErrAppendParentSym(pAggType.getAggregate(), pctx);
}
ErrAppendName(pAggType.getAggregate().name);
}
ErrAppendTypeParameters(pAggType.GetTypeArgsThis(), pctx, true);
break;
}
case TypeKind.TK_TypeParameterType:
if (null == pType.GetName())
{
// It's a standard type variable.
if (pType.AsTypeParameterType().IsMethodTypeParameter())
{
ErrAppendChar('!');
}
ErrAppendChar('!');
ErrAppendPrintf("{0}", pType.AsTypeParameterType().GetIndexInTotalParameters());
}
else
{
ErrAppendName(pType.GetName());
}
break;
case TypeKind.TK_ErrorType:
if (pType.AsErrorType().HasParent())
{
Debug.Assert(pType.AsErrorType().nameText != null && pType.AsErrorType().typeArgs != null);
ErrAppendParentType(pType, pctx);
ErrAppendName(pType.AsErrorType().nameText);
ErrAppendTypeParameters(pType.AsErrorType().typeArgs, pctx, true);
}
else
{
// Load the string "<error>".
Debug.Assert(null == pType.AsErrorType().typeArgs);
ErrAppendId(MessageID.ERRORSYM);
}
break;
case TypeKind.TK_NullType:
// Load the string "<null>".
ErrAppendId(MessageID.NULL);
break;
case TypeKind.TK_OpenTypePlaceholderType:
// Leave blank.
break;
case TypeKind.TK_BoundLambdaType:
ErrAppendId(MessageID.AnonMethod);
break;
case TypeKind.TK_UnboundLambdaType:
ErrAppendId(MessageID.Lambda);
break;
case TypeKind.TK_MethodGroupType:
ErrAppendId(MessageID.MethodGroup);
break;
case TypeKind.TK_ArgumentListType:
ErrAppendString(TokenFacts.GetText(TokenKind.ArgList));
break;
case TypeKind.TK_ArrayType:
{
CType elementType = pType.AsArrayType().GetBaseElementType();
if (null == elementType)
{
Debug.Assert(false, "No element type");
break;
}
ErrAppendType(elementType, pctx);
for (elementType = pType;
elementType != null && elementType.IsArrayType();
elementType = elementType.AsArrayType().GetElementType())
{
int rank = elementType.AsArrayType().rank;
// Add [] with (rank-1) commas inside
ErrAppendChar('[');
// known rank.
if (rank == 1)
{
if (!elementType.AsArrayType().IsSZArray)
{
ErrAppendChar('*');
}
}
else
{
for (int i = rank; i > 1; --i)
{
ErrAppendChar(',');
}
}
ErrAppendChar(']');
}
break;
}
case TypeKind.TK_VoidType:
ErrAppendName(GetNameManager().Lookup(TokenFacts.GetText(TokenKind.Void)));
break;
case TypeKind.TK_ParameterModifierType:
// add ref or out
ErrAppendString(pType.AsParameterModifierType().isOut ? "out " : "ref ");
// add base type name
ErrAppendType(pType.AsParameterModifierType().GetParameterType(), pctx);
break;
case TypeKind.TK_PointerType:
// Generate the base type.
ErrAppendType(pType.AsPointerType().GetReferentType(), pctx);
{
// add the trailing *
ErrAppendChar('*');
}
break;
case TypeKind.TK_NullableType:
ErrAppendType(pType.AsNullableType().GetUnderlyingType(), pctx);
ErrAppendChar('?');
break;
case TypeKind.TK_NaturalIntegerType:
default:
// Shouldn't happen.
Debug.Assert(false, "Bad type kind");
break;
}
}
public static string GetDisplayName(OperatorKind op) => TokenFacts.GetText(GetInfo(op).TokenKind);
public Token NextToken()
{
var tok = new Token();
skipWhitespace();
switch (ch)
{
case '=':
if (peekChar() == '=')
{
var ch = this.ch;
readChar();
tok = new Token(TokenType.EQUALS_EQUALS, $"{ch}{this.ch}");
}
else
{
tok = makeToken(TokenType.EQUALS);
}
break;
case '+':
tok = makeToken(TokenType.PLUS);
break;
case ';':
tok = makeToken(TokenType.SEMICOLON);
break;
case ',':
tok = makeToken(TokenType.COMMA);
break;
case '(':
tok = makeToken(TokenType.LPAREN);
break;
case ')':
tok = makeToken(TokenType.RPAREN);
break;
case '{':
tok = makeToken(TokenType.LBRACE);
break;
case '}':
tok = makeToken(TokenType.RBRACE);
break;
case '!':
if (peekChar() == '=')
{
var ch = this.ch;
readChar();
tok = new Token(TokenType.BANG_EQUALS, $"{ch}{this.ch}");
}
else
{
tok = makeToken(TokenType.BANG);
}
break;
case '-':
tok = makeToken(TokenType.MINUS);
break;
case '/':
tok = makeToken(TokenType.SLASH);
break;
case '*':
tok = makeToken(TokenType.ASTERISK);
break;
case '<':
tok = makeToken(TokenType.LT);
break;
case '>':
tok = makeToken(TokenType.GT);
break;
case '"':
tok.Type = TokenType.STRING;
tok.Literal = readString();
break;
case '[':
tok = makeToken(TokenType.LBRACKET);
break;
case ']':
tok = makeToken(TokenType.RBRACKET);
break;
case ':':
tok = makeToken(TokenType.COLON);
break;
case '\0':
tok.Literal = "";
tok.Type = TokenType.EOF;
break;
default:
if (ch.IsLetter())
{
tok.Literal = readIdentifier();
tok.Type = TokenFacts.LookupIdent(tok.Literal);
return(tok);
}
else if (ch.IsDigit())
{
tok.Literal = readNumber();
tok.Type = TokenType.INT;
return(tok);
}
else
{
tok = makeToken(TokenType.ILLEGAL);
}
break;
}
readChar();
return(tok);
}
