public void TestWrap()
{
var s = PrinterMonad.Wrap("test");
// note: AWKWARD
// run test and watch debug prompt to see if working
// should print 'test' three times
s("input");
s("test");
s("a");
}
public void TestFlatten()
{
var r = new List <PrinterMonad <int> >();
PrinterMonad <PrinterMonad <int> > p = r.Add;
var q = p.Flatten();
// note: AWKWARD
// can't really verify what the printers are, just that they were made and inserted
r.Count.AssertEquals(0);
q(5);
r.Count.AssertEquals(1);
q(6);
r.Count.AssertEquals(2);
}
public void TestTransform()
{
var r = new List <string>();
PrinterMonad <string> p = r.Add;
// note: BROKEN, goes backwards from string to int, instead of forward from int to string
var q = p.Transform <int, string>(e => e + "");
r.SequenceEqual(new string[0]).AssertTrue();
q(5);
r.SequenceEqual(new[] { "5" }).AssertTrue();
q(8);
r.SequenceEqual(new[] { "5", "8" }).AssertTrue();
}
/// <summary>
/// Returns a printer that transforms values into a printer then prints that printer with the given printer printer.
///
/// AWKWARD: The intermediate printer inherits awkwardness from Wrap's awkwardness.
/// </summary>
public static PrinterMonad <T> Flatten <T>(this PrinterMonad <PrinterMonad <T> > printerOfPrinter)
{
return(input => printerOfPrinter(Wrap(input)));
}
/// <summary>
/// Returns a parser that uses the given parser but transforms its resulting value with the given transformation.
///
/// BROKEN: The transformation goes backwards! The resulting printer expects values of type TIn instead of TOut.
/// </summary>
public static PrinterMonad <TIn> Transform <TIn, TOut>(this PrinterMonad <TOut> printer, Func <TIn, TOut> transformation)
{
return(input => printer(transformation(input)));
}
