[slider] Accepts custom predicate

lib/slideHelper.js

@@ -22,7 +22,9 @@ const slideNext = (host, window, hostPos, windowPos, len = 1) => {
 	return (len);
 };
 
-const startSliding = (k, host, guest, window, windowPos) => {
+const startSliding = (k, predicate, host, guest, window, windowPos) => {
+
+	const test = predicate ?  predicate : isEq;
 
 	const firstMatch = host.findIndex(wrap(isEq, window[0]));
 
@@ -38,14 +40,14 @@ const startSliding = (k, host, guest, window, windowPos) => {
 
 };
 
-const slide = (k, host, guest) => {
+const slide = (k, predicate, host, guest) => {
 
 	if (k > host.length) return errors.WIN_TOO_LARGE_HOST;
 	if (k > guest.length) return errors.WIN_TOO_LARGE_GUEST;
 
 	// Create a new window and start sliding
 	const window = guest.slice(0, k);
-	return startSliding(k, host, guest, window, 0);
+	return startSliding(k, predicate, host, guest, window, 0);
 }
 
 module.exports = slide;

lib/slider.js

@@ -5,12 +5,13 @@ const slideHelper = require('./slideHelper');
 class Slider {
 	constructor (options) {
 		this.windowSize = options.size;
+		this.predicate = options.predicate;
 		this.prefer = options.prefer;
 		this.accepting = options.accepting;
 	}
 
 	slide (host, guest) {
-		return slideHelper(this.windowSize, host, guest);
+		return slideHelper(this.windowSize, this.predicate, host, guest);
 	}
 };