private static string ToString(object value)
{
var sb = new StringBuilder();
EvaluatorEngine.FormatLiteral(value, sb);
return(sb.ToString());
}
/// <summary>
/// Create an evaluator that always evaluates to the given
/// constant <paramref name="value"/>. This is useful to
/// substitute default values where no expression is provided.
/// </summary>
/// <param name="value">The constant value.</param>
/// <param name="clause">The value for the evaluator's <see cref="Clause"/>
/// property (optional).</param>
public static ExpressionEvaluator CreateConstant(object value, string clause = null)
{
var engine = new EvaluatorEngine();
engine.EmitValue(value);
engine.EmitCode(OpCode.End);
engine.Commit();
return(new ExpressionEvaluator(engine, clause ?? ToString(value)));
}
public ParseState(string text, int index, EvaluatorEngine target,
StringComparison comparison)
{
_text = text ?? string.Empty;
Position = _index = index;
Token = TokenType.None;
Value = null;
Target = target ?? new EvaluatorEngine();
Comparison = comparison;
_buffer = new StringBuilder();
}
private ExpressionEvaluator(EvaluatorEngine engine, string clause = null)
{
Clause = clause ?? string.Empty;
_engine = engine;
}
