public static ProblemQualified <T> ForTerminal(string terminal) => new ProblemQualified <T>(Either <Array1 <string>, T> .FromLeft(Array1.Build(terminal)), Enumerable.Empty <string>());
public static ProblemQualified <T> ForTerminal(string terminal, IEnumerable <string> nonTerminalWarnings) => new ProblemQualified <T>(Either <Array1 <string>, T> .FromLeft(Array1.Build(terminal)), nonTerminalWarnings);
public void ReportTerminal(string terminal) => ReportTerminals(Array1.Build(terminal));