Invercargill/src/lib/Iterate.vala

using Invercargill.DataStructures;
namespace Invercargill.Iterate {

    public static Enumerable<T> single<T>(T item) {
        var buffer = new Buffer<T>(1);
        non_error(() => buffer[0] = item);
        return buffer.seal();
    }

    public static Enumerable<int> range(int from, int to, int increment = 1) {
        return new Generators.Range(from, to, increment);
    }

    public static Enumerable<T> nothing<T>() {
        return new Generators.Empty<T>();
    }

    public static Enumerable<string> directory(string path, uint flags = 0) throws FileError {
        return new Generators.Directory(Dir.open(path, flags));
    }

    public static Enumerable<T> on<T>(Generators.GeneratorDelegate<T> function) {
        return new Generators.Function<T>(function);
    }

    public static Enumerable<T> these<T>(T item1, ...) {
        var series = new Series<T>();
        var args = va_list();
        series.add(item1);
        while(true) {
            T? item = args.arg<T>();
            if(item == null) {
                break;
            }
            series.add(item);
        }
        return series.seal();
    }


}