public void EvalAsIs(double expected)
{
var sut = new NodeNumber(expected);
var actual = sut.Eval(null);
Assert.Equal(expected, actual);
}
public override string ToString()
{
return(NodeNumber.ToString());
}
private INode ParseLeaf()
{
if (tokenizer.currentToken == Token.Number)
{
var node = new NodeNumber(tokenizer.number);
tokenizer.NextToken();
return(node);
}
if (tokenizer.currentToken == Token.OpenParens)
{
tokenizer.NextToken();
var node = ParseAddSubtract();
if (tokenizer.currentToken != Token.CloseParens)
{
throw new SyntaxException("Falta cerrar paréntesis");
}
tokenizer.NextToken();
return(node);
}
if (tokenizer.currentToken == Token.Identifier)
{
var name = tokenizer.identifier;
tokenizer.NextToken();
if (tokenizer.currentToken != Token.OpenParens)
{
NodeVariable node = new NodeVariable(name);
if (!node.isReserved())
{
variables.Add(name);
}
return(node);
}
else
{
tokenizer.NextToken();
var arguments = new List <INode>();
while (true)
{
arguments.Add(ParseAddSubtract());
if (tokenizer.currentToken == Token.Comma)
{
tokenizer.NextToken();
continue;
}
break;
}
if (tokenizer.currentToken != Token.CloseParens)
{
throw new SyntaxException("Falta cerrar paréntesis");
}
tokenizer.NextToken();
return(new NodeFunctionCall(name, arguments.ToArray()));
}
}
throw new SyntaxException(GetUnexpectedTokenMessage(tokenizer.currentToken));
}
// Parse a leaf node
// (For the moment this is just a number)
Node ParseLeaf()
{
// Is it a number?
if (m_tokeniser.getToken == Token.Number)
{
var node = new NodeNumber(m_tokeniser.getNumber);
m_tokeniser.NextToken();
return(node);
}
// Parenthesis?
if (m_tokeniser.getToken == Token.OpenParens)
{
// Skip '('
m_tokeniser.NextToken();
// Parse a top-level expression
var node = ParseAddSubtract();
// Check and skip ')'
if (m_tokeniser.getToken != Token.CloseParens)
{
throw new Exception("Missing close parenthesis");
}
m_tokeniser.NextToken();
// Return
return(node);
}
// Variable
if (m_tokeniser.getToken == Token.Identifier)
{
// Capture the name and skip it
var name = m_tokeniser.getIdentifier;
m_tokeniser.NextToken();
// Parens indicate a function call, otherwise just a variable
if (m_tokeniser.getToken != Token.OpenParens)
{
// Variable
return(new NodeVariable(name));
}
else
{
// Function call
// Skip parens
m_tokeniser.NextToken();
// Parse arguments
var arguments = new List <Node>();
while (true)
{
// Parse argument and add to list
arguments.Add(ParseAddSubtract());
// Is there another argument?
if (m_tokeniser.getToken == Token.Comma)
{
m_tokeniser.NextToken();
continue;
}
// Get out
break;
}
// Check and skip ')'
if (m_tokeniser.getToken != Token.CloseParens)
{
throw new Exception("Missing close parenthesis");
}
m_tokeniser.NextToken();
// Create the function call node
return(new NodeFunctionCall(name, arguments.ToArray()));
}
}
// Don't Understand
throw new Exception($"Unexpect token: {m_tokeniser.getToken}");
}
// ParseLeaf is the lowest level of the expression parsers.
// It is used to extract the fundamental elements of an expression.
// These elements are numbers, function calls and arrays.
Node ParseLeaf()
{
// NodeNumber:
// If current token is a number we simply extract it as a NodeNumber.
if (fCurrentToken.Type == TokenType.Integer)
{
var node = new NodeNumber(fCurrentToken.IntValue());
ReadNextToken();
return(node);
}
// Parenthesis:
// If an open parenthesis is read, it must be skipped and the expression
// it encloses must be parsed. We must also check again at the end of the
// expression if the parenthesis is correctly closed otherwise an exception
// is thrown.
if (fCurrentToken.Equals(TokenType.Symbol, "("))
{
// Skip '('
ReadNextToken();
// Check for "others" statement that is commonly used in VHDL.
if (fCurrentToken.Equals(TokenType.Word, "others"))
{
fCurrentToken = fLexicalAnalyser.SkipOver(TokenType.Symbol, "'");
var node = new NodeNumber(fCurrentToken.IntValue());
fCurrentToken = fLexicalAnalyser.SkipOver(TokenType.Symbol, ")");
return(node);
}
// Else we have an expression inside of parenthesis.
else
{
// Parse a top-level expression
var arguments = new List <Node> ();
while (true)
{
// Parse argument and add to list
arguments.Add(ParseAddSubtract());
// Is there another argument?
if (fCurrentToken.Equals(TokenType.Symbol, ","))
{
ReadNextToken();
continue;
}
// Get out
break;
}
// Check and skip ')'
if (!fCurrentToken.Equals(TokenType.Symbol, ")"))
{
throw new ParserException("Missing close parenthesis");
}
ReadNextToken();
// Return
return(new NodeArray(arguments.ToArray()));
}
}
// Single/Double Quote Literals:
// In vhdl we can have single digit values enclosed in signle quote literals and longer values
// enclosed in double quote literals. We must therefore extract the number from within these quotation literals.
if (fCurrentToken.Equals(TokenType.Symbol, "\"") || fCurrentToken.Equals(TokenType.Symbol, "\'"))
{
// Skip '"'
ReadNextToken(); //Read the number
var node = new NodeNumber(fCurrentToken.IntValue());
ReadNextToken(); //Skip the number
// Check and skip ')'
if (!(fCurrentToken.Equals(TokenType.Symbol, "\"") || fCurrentToken.Equals(TokenType.Symbol, "\'")))
{
throw new ParserException("Missing closing quote literals");
}
ReadNextToken();
// Return
return(node);
}
if (fCurrentToken.Type == TokenType.Word)
{
// Parse a top-level expression
var name = fCurrentToken.Value;
ReadNextToken();
if (fCurrentToken.Equals(TokenType.Symbol, "\'"))
{
//Type Attribute has been requested
ReadNextToken();
var attribute = DetermineAttribute(fCurrentToken.Value, name);
var node = new NodeNumber(attribute);
ReadNextToken(); //Skip the found attribute
return(node);
}
else if (!fCurrentToken.Equals(TokenType.Symbol, "("))
{
if (ConstantList.Any(x => x.Identifier == name))
{
ConstantDeclaration result = ConstantList.Find(x => x.Identifier == name);
var node = new NodeNumber(result.Value);
return(node);
}
else if (ConstantList.Any(x => x.Identifier == name.ToUpper()))
{
ConstantDeclaration result = ConstantList.Find(x => x.Identifier == name.ToUpper());
var node = new NodeNumber(result.Value);
return(node);
}
else if (ConstantList.Any(x => x.Identifier == name.ToLower()))
{
ConstantDeclaration result = ConstantList.Find(x => x.Identifier.ToUpper() == name.ToLower());
var node = new NodeNumber(result.Value);
return(node);
}
else
{
throw new ParserException("Constant value is unknown.");
}
}
else
{
// Function call
// Skip parens
ReadNextToken();
// Parse arguments
var arguments = new List <Node> ();
while (true)
{
// Parse argument and add to list
arguments.Add(ParseAddSubtract());
// Is there another argument?
if (fCurrentToken.Equals(TokenType.Symbol, ","))
{
ReadNextToken();
continue;
}
// Get out
break;
}
// Check and skip ')'
if (!fCurrentToken.Equals(TokenType.Symbol, ")"))
{
throw new ParserException("Missing Closing Parenthesis");
}
ReadNextToken();
// Create the function call node
return(new NodeFunctionCall(name, arguments.ToArray()));
}
}
// Don't Understand
throw new ParserException("Expected ; and end of line but instead got: " + fCurrentToken.Value);
}
