public bool TryParse(PrioritizedString expr, ParameterInfo paramInfo, out Expression parsed)
{
var minPriorityInds = expr.Priorities.GetMinIndexes();
var whereParts = expr.SplitOnSubset("where", minPriorityInds);
if (whereParts.Length > 2)
{
throw new ParseException("Too many 'where'!");
}
if (whereParts.Length == 1)
{
parsed = null;
return(false);
}
var mainFunc = whereParts[0];
if (mainFunc.Input.Last() == ',')
{
mainFunc = mainFunc.Substring(0, mainFunc.Input.Length - 1);
}
var parameterExpressions = new Dictionary <string, PrioritizedString>();
foreach (Match match in ParameterRe.Matches(whereParts[1].Input))
{
var(paramName, paramExpr) = (match.Groups["paramName"].Value, match.Groups["paramExpr"].Value);
if (paramInfo.Parameters.ContainsKey(paramName))
{
throw new ParseException($"Parameter {paramName} is defined multiple times");
}
paramInfo.Parameters[paramName] = Expression.Parameter(typeof(double), paramName);
parameterExpressions[paramName] = new PrioritizedString(paramExpr);
}
var parameterExprs = parameterExpressions
.ToDictionary(
nameWithExpr => nameWithExpr.Key,
nameWithExpr => Combinator.ParseFunctionalExpression(nameWithExpr.Value, paramInfo)
);
var mainExpr = Combinator.ParseFunctionalExpression(mainFunc, paramInfo);
var paramReplacer = new ParameterReplacerVisitor(parameterExprs);
parsed = paramReplacer.Visit(mainExpr);
return(true);
}
public bool TryParse(PrioritizedString expr, ParameterInfo paramInfo, out Expression parsed)
{
expr = expr.Trim();
var exprStr = expr.Input;
if (!Brackets.AreMatching(exprStr.First(), exprStr.Last()))
{
parsed = null;
return(false);
}
var exprWithoutBrackets = expr.Substring(1, expr.Input.Length - 2);
parsed = Combinator.ParseFunctionalExpression(exprWithoutBrackets, paramInfo);
return(true);
}