+ function fixArrayIndex (array, index) {
+ return (index < 0) ? Math.max(0, array.length + index)
+ : Math.min(array.length, index);
+ }
+
+
+ function replaceSim (array, index, removeCount, insert) {
+ var add = insert ? insert.length : 0,
+ length = array.length,
+ pos = fixArrayIndex(array, index);
+
+
+ if (pos === length) {
+ if (add) {
+ array.push.apply(array, insert);
+ }
+ } else {
+ var remove = Math.min(removeCount, length - pos),
+ tailOldPos = pos + remove,
+ tailNewPos = tailOldPos + add - remove,
+ tailCount = length - tailOldPos,
+ lengthAfterRemove = length - remove,
+ i;
+
+ if (tailNewPos < tailOldPos) {
+ for (i = 0; i < tailCount; ++i) {
+ array[tailNewPos+i] = array[tailOldPos+i];
+ }
+ } else if (tailNewPos > tailOldPos) {
+ for (i = tailCount; i--; ) {
+ array[tailNewPos+i] = array[tailOldPos+i];
+ }
+ }
+
+ if (add && pos === lengthAfterRemove) {
+ array.length = lengthAfterRemove;
+ array.push.apply(array, insert);
+ } else {
+ array.length = lengthAfterRemove + add;
+ for (i = 0; i < add; ++i) {
+ array[pos+i] = insert[i];
+ }
+ }
+ }
+
+ return array;
+ }
+
+ function replaceNative (array, index, removeCount, insert) {
+ if (insert && insert.length) {
+ if (index < array.length) {
+ array.splice.apply(array, [index, removeCount].concat(insert));
+ } else {
+ array.push.apply(array, insert);
+ }
+ } else {
+ array.splice(index, removeCount);
+ }
+ return array;
+ }
+
+ function eraseSim (array, index, removeCount) {
+ return replaceSim(array, index, removeCount);
+ }
+
+ function eraseNative (array, index, removeCount) {
+ array.splice(index, removeCount);
+ return array;
+ }
+
+ function spliceSim (array, index, removeCount) {
+ var pos = fixArrayIndex(array, index),
+ removed = array.slice(index, fixArrayIndex(array, pos+removeCount));
+
+ if (arguments.length < 4) {
+ replaceSim(array, pos, removeCount);
+ } else {
+ replaceSim(array, pos, removeCount, slice.call(arguments, 3));
+ }
+
+ return removed;
+ }
+
+ function spliceNative (array) {
+ return array.splice.apply(array, slice.call(arguments, 1));
+ }
+
+ var erase = supportsSplice ? eraseNative : eraseSim,
+ replace = supportsSplice ? replaceNative : replaceSim,
+ splice = supportsSplice ? spliceNative : spliceSim;
+
+
+