/// <summary>
/// Process the term2 rule.
/// </summary>
/// <remarks>
///
/// term2 ::= '*' factor term2 |
/// '/' factor term2 |
/// {empty}
///
/// </remarks>
/// <returns>Parsed node.</returns>
protected virtual EvalNode ParseTerm2()
{
if (Tokeniser.Next(TokenType.Multiply))
{
EvalNode op = new EvalNodeBinaryOp(EvalNodeBinaryOp.BinaryOp.Multiply, ParseFactor(), Language);
EvalNode term2 = ParseTerm2();
if (term2 != null)
{
term2.Prepend(op);
}
return(op);
}
if (Tokeniser.Next(TokenType.Divide))
{
EvalNode op = new EvalNodeBinaryOp(EvalNodeBinaryOp.BinaryOp.Divide, ParseFactor(), Language);
EvalNode term2 = ParseTerm2();
if (term2 != null)
{
term2.Prepend(op);
}
return(op);
}
return(null);
}
/// <summary>
/// Parse the provided input string.
/// </summary>
/// <param name="input">Input text.</param>
public virtual void Parse(string input)
{
if (!string.IsNullOrEmpty(input))
{
// Generate entire set of tokens in one go
_tokeniser = new Tokeniser(input, Language);
// Parse into abstract syntax tree
EvalNode eval = ParseExpression();
// Should be no more input available
if (Tokeniser.Peek.Type != TokenType.EndOfInput)
{
throw new ParseException(Tokeniser.Peek.Index, "Found '" + Tokeniser.Peek.Type.ToString() + "' instead of end of input");
}
else
{
_root = eval;
}
}
else
{
_root = null;
}
}
/// <summary>
/// Parse the 'expression2' rule.
/// </summary>
/// <remarks>
///
/// expression2 ::= '+' term expression2 |
/// '-' term expression2 |
/// {empty}
///
/// </remarks>
/// <returns>Parsed node.</returns>
protected virtual EvalNode ParseExpression2()
{
if (Tokeniser.Next(TokenType.Plus))
{
EvalNode op = new EvalNodeBinaryOp(EvalNodeBinaryOp.BinaryOp.Add, ParseTerm(), Language);
EvalNode expr2 = ParseExpression2();
if (expr2 != null)
{
expr2.Prepend(op);
}
return(op);
}
if (Tokeniser.Next(TokenType.Minus))
{
EvalNode op = new EvalNodeBinaryOp(EvalNodeBinaryOp.BinaryOp.Subtract, ParseTerm(), Language);
EvalNode expr2 = ParseExpression2();
if (expr2 != null)
{
expr2.Prepend(op);
}
return(op);
}
return(null);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeCondLogicOp node.
/// </summary>
/// <param name="operation">Specifies the binary compare to represent.</param>
/// <param name="child1">Specifies the first child node.</param>
/// <param name="child2">Specifies the second child node.</param>
public EvalNodeCondLogicOp(CompareOp operation,
EvalNode child1,
EvalNode child2)
{
_operation = operation;
Append(child1);
Append(child2);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeCondLogicOp node.
/// </summary>
/// <param name="operation">Specifies the binary compare to represent.</param>
/// <param name="child">Specifies the first child node.</param>
/// <param name="language">Language used for evaluation.</param>
public EvalNodeCondLogicOp(CompareOp operation,
EvalNode child,
Language language)
{
_language = language;
_operation = operation;
Append(child);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeUnaryOp node.
/// </summary>
/// <param name="operation">Specifies the unary operation to represent.</param>
/// <param name="child">Specifies the child node.</param>
/// <param name="language">Language used for evaluation.</param>
public EvalNodeUnaryOp(UnaryOp operation,
EvalNode child,
Language language)
{
_operation = operation;
_language = language;
Append(child);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeShiftOp node.
/// </summary>
/// <param name="operation">Specifies the shift operation to represent.</param>
/// <param name="child">Specifies the first child node.</param>
/// <param name="language">Language used for evaluation.</param>
public EvalNodeShiftOp(ShiftOp operation,
EvalNode child,
Language language)
{
_operation = operation;
_language = language;
Append(child);
}
/// <summary>
/// Appends a node to the end of the child collection.
/// </summary>
/// <param name="item">Reference to node for appending.</param>
public void Append(EvalNode item)
{
if (item == null)
{
throw new ArgumentNullException("item", "cannot append an empty reference");
}
else
{
_children.Add(item);
item.Parent = this;
}
}
/// <summary>
/// Parse the 'term' rule.
/// </summary>
/// <remarks>
///
/// term ::= factor term2
///
/// </remarks>
/// <returns>Parsed node.</returns>
protected virtual EvalNode ParseTerm()
{
EvalNode factor = ParseFactor();
EvalNode term2 = ParseTerm2();
if (term2 != null)
{
term2.Prepend(factor);
return(term2);
}
else
{
return(factor);
}
}
/// <summary>
/// Parse the 'expression' rule.
/// </summary>
/// <remarks>
///
/// expression ::= term expression2
///
/// </remarks>
/// <returns>Parsed node.</returns>
protected virtual EvalNode ParseExpression()
{
EvalNode term = ParseTerm();
EvalNode expr2 = ParseExpression2();
if (expr2 != null)
{
expr2.Prepend(term);
return(expr2.Root);
}
else
{
return(term.Root);
}
}
/// <summary>
/// Parse the 'primary' rule.
/// </summary>
/// <remarks>
///
/// primary ::= integer-literal |
/// real-literal
/// '(' expression ')'
///
/// </remarks>
/// <returns>Parsed node.</returns>
protected virtual EvalNode ParsePrimary()
{
if ((Tokeniser.Peek.Type == TokenType.IntegerLiteral) ||
(Tokeniser.Peek.Type == TokenType.RealLiteral))
{
return(new EvalNodeLiteral(Tokeniser.Peek.TypeCode, Tokeniser.Next().Value, Language));
}
if (Tokeniser.Next(TokenType.OpenRoundBracket))
{
EvalNode expr = ParseExpression();
if (!Tokeniser.Next(TokenType.CloseRoundBracket))
{
if (Tokeniser.Peek.Type == TokenType.EndOfInput)
{
throw new ParseException(Tokeniser.Peek.Index, "Found '" + Tokeniser.Peek.Type.ToString() + "' instead of expected ')'");
}
else
{
throw new ParseException(Tokeniser.Peek.Index, "Found '" + Tokeniser.Peek.Type.ToString() + "' at index '" + Tokeniser.Peek.Index + "' instead of expected ')'");
}
}
return(expr);
}
if (Tokeniser.Peek.Type == TokenType.EndOfInput)
{
throw new ParseException(Tokeniser.Peek.Index, "Found '" + Tokeniser.Peek.Type.ToString() + "' instead of some more input");
}
else
{
throw new ParseException(Tokeniser.Peek.Index, "Found '" + Tokeniser.Peek.Type.ToString() + "' at index '" + Tokeniser.Peek.Index + "' instead of either a primary or '('");
}
}
/// <summary>
/// Initialize a new instance of the EvalNodeArgList class.
/// </summary>
/// <param name="argument">Initial argument to store.</param>
/// <param name="language">Language used for evaluation.</param>
public EvalNodeArgList(EvalNode argument,
Language language)
{
_language = language;
Append(argument);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeExponent node.
/// </summary>
/// <param name="child">Specifies the first child node.</param>
/// <param name="language">Language syntax and semantics to use.</param>
public EvalNodeExponent(EvalNode child,
Language language)
{
_language = language;
Append(child);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeNullCoalescing node.
/// </summary>
/// <param name="child">Specifies the child node.</param>
public EvalNodeNullCoalescing(EvalNode child)
{
Append(child);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeConcatenate node.
/// </summary>
/// <param name="child">Specifies the first child node.</param>
public EvalNodeConcatenate(EvalNode child)
{
Append(child);
}
/// <summary>
/// Instantiate a new instance of the EvalNodeConditional node.
/// </summary>
/// <param name="child1">Specifies the first child.</param>
/// <param name="child2">Specifies the second child.</param>
public EvalNodeConditional(EvalNode child1,
EvalNode child2)
{
Append(child1);
Append(child2);
}
/// <summary>
/// Initialize a new instance of the EvalNodeArrayIndex class.
/// </summary>
/// <param name="child">Specifies the child node.</param>
/// <param name="language">Language used for evaluation.</param>
public EvalNodeArrayIndex(EvalNode child,
Language language)
{
_language = language;
Append(child);
}
