/// <summary>
/// Parses a specified logical expression into expression tree within given context.
/// </summary>
/// <typeparam name="TContext">The type identifier of the context within which the expression is interpreted.</typeparam>
/// <param name="expression">The logical expression.</param>
/// <returns>
/// A delegate containing the compiled version of the lambda expression described by created expression tree.
/// </returns>
/// <exception cref="System.ArgumentNullException">expression;Expression not provided.</exception>
/// <exception cref="ParseErrorException"></exception>
public Func <TContext, bool> Parse <TContext>(string expression)
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression), "Expression not provided.");
}
lock (_locker)
{
try
{
Clear();
ContextType = typeof(TContext);
var param = Expression.Parameter(typeof(TContext));
ContextExpression = param;
Expr = expression;
Wall = new TypeWall(expression);
var expressionTree = ParseExpression();
var lambda = Expression.Lambda <Func <TContext, bool> >(expressionTree, param);
return(lambda.Compile());
}
catch (ParseErrorException)
{
throw;
}
catch (Exception e)
{
throw new ParseErrorException("Parse fatal error.", e);
}
}
}
public Expr(string expression)
{
ExprString = expression;
Wall = new TypeWall(expression);
}
