/// <summary>
/// Evaluates a derivation of the form:
/// Expression= Expression add Expression | Expression sub Expression | integer
/// </summary>
/// <remarks>
/// The production rules are:
/// Expression -> Expression add Expression
/// Expression -> Expression sub Expression
/// Expression -> integer
/// </remarks>
/// <param name="node">The <see cref="ParseNode"/> to evaluate</param>
/// <param name="state">A user supplied state object. What it should be depends on the production's associated code block</param>
/// <returns>The result of the evaluation</returns>
internal static int EvaluateExpression(ParseNode node, object state)
{
if ((GloryDemo.Test2Parser.integer == node.SymbolId))
{
return((int)(Test2Parser._ChangeType(node.Value, typeof(int))));
}
if ((false == node.IsNonTerminal))
{
return((int)(Test2Parser._ChangeType(0, typeof(int))));
}
int result = Test2Parser.EvaluateExpression(node.Children[0], state);
int i = 2;
for (
; (i < node.Children.Length);
)
{
if ((node.Children[(i - 1)].SymbolId == GloryDemo.Test2Parser.add))
{
result = (result + Test2Parser.EvaluateExpression(node.Children[i], state));
}
else
{
result = (result - Test2Parser.EvaluateExpression(node.Children[i], state));
}
i = (i + 2);
}
return((int)(Test2Parser._ChangeType(result, typeof(int))));
}
/// <summary>
/// Evaluates a derivation of the form:
/// Expression= Expression add Expression | Expression sub Expression | integer
/// </summary>
/// <remarks>
/// The production rules are:
/// Expression -> Expression add Expression
/// Expression -> Expression sub Expression
/// Expression -> integer
/// </remarks>
/// <param name="node">The <see cref="ParseNode"/> to evaluate</param>
/// <param name="state">A user supplied state object. What it should be depends on the production's associated code block</param>
/// <returns>The result of the evaluation</returns>
public static int Evaluate(ParseNode node, object state)
{
return(Test2Parser.EvaluateExpression(node, state));
}
/// <summary>
/// Evaluates a derivation of the form:
/// Expression= Expression add Expression | Expression sub Expression | integer
/// </summary>
/// <remarks>
/// The production rules are:
/// Expression -> Expression add Expression
/// Expression -> Expression sub Expression
/// Expression -> integer
/// </remarks>
/// <param name="node">The <see cref="ParseNode"/> to evaluate</param>
/// <returns>The result of the evaluation</returns>
public static int Evaluate(ParseNode node)
{
return(Test2Parser.EvaluateExpression(node, null));
}