 		assertEqual((literal("x") | literal("y"))("xy")?.0, "x")
 	}
 
+
+	// MARK: Repetition
 
 	let zeroOrMore = literal("x")*
 


final class MadnessTests: XCTestCase {

	// MARK: Terminals

	func testLiteralParsersParseAPrefixOfTheInput() {
		assertEqual(literal("foo")("foot")?.1, "t")

	}


	// MARK: Alternation

	let alternation = literal("x") | (literal("y") --> const(1))

	func testAlternationParsesEitherAlternative() {
