use == and != to enable handling null/undefined

lib/runtime/dart/_internal.js

 var _internal;
 (function(exports) {
   'use strict';
   class EfficientLength extends core.Object {
   }
   let ListIterable$ = dart.generic(function(E) {
     class ListIterable extends collection.IterableBase$(E) {
       ListIterable() {
         super.IterableBase();
       }
       get iterator() {
         return new ListIterator(this);
       }
       forEach(action) {
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           action(this.elementAt(i));
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
       }
       get isEmpty() {
-        return this.length === 0;
+        return this.length == 0;
       }
       get first() {
-        if (this.length === 0)
+        if (this.length == 0)
           throw IterableElementError.noElement();
         return this.elementAt(0);
       }
       get last() {
-        if (this.length === 0)
+        if (this.length == 0)
           throw IterableElementError.noElement();
         return this.elementAt(dart.notNull(this.length) - 1);
       }
       get single() {
-        if (this.length === 0)
+        if (this.length == 0)
           throw IterableElementError.noElement();
         if (dart.notNull(this.length) > 1)
           throw IterableElementError.tooMany();
         return this.elementAt(0);
       }
       contains(element) {
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           if (dart.equals(this.elementAt(i), element))
             return true;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return false;
       }
       every(test) {
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           if (!dart.notNull(test(this.elementAt(i))))
             return false;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return true;
       }
       any(test) {
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           if (test(this.elementAt(i)))
             return true;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return false;
       }
       firstWhere(test, opts) {
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           let element = this.elementAt(i);
           if (test(element))
             return element;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       lastWhere(test, opts) {
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
         let length = this.length;
         for (let i = dart.notNull(length) - 1; dart.notNull(i) >= 0; i = dart.notNull(i) - 1) {
           let element = this.elementAt(i);
           if (test(element))
             return element;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       singleWhere(test) {
         let length = this.length;
         let match = null;
         let matchFound = false;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           let element = this.elementAt(i);
           if (test(element)) {
             if (matchFound) {
               throw IterableElementError.tooMany();
             }
             matchFound = true;
             match = element;
           }
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         if (matchFound)
           return match;
         throw IterableElementError.noElement();
       }
       join(separator) {
         if (separator === void 0)
           separator = "";
         let length = this.length;
         if (!dart.notNull(separator.isEmpty)) {
-          if (length === 0)
+          if (length == 0)
             return "";
           let first = `${this.elementAt(0)}`;
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
           let buffer = new core.StringBuffer(first);
           for (let i = 1; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
             buffer.write(separator);
             buffer.write(this.elementAt(i));
-            if (length !== this.length) {
+            if (length != this.length) {
               throw new core.ConcurrentModificationError(this);
             }
           }
           return buffer.toString();
         } else {
           let buffer = new core.StringBuffer();
           for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
             buffer.write(this.elementAt(i));
-            if (length !== this.length) {
+            if (length != this.length) {
               throw new core.ConcurrentModificationError(this);
             }
           }
           return buffer.toString();
         }
       }
       where(test) {
         return super.where(test);
       }
       map(f) {
         return new MappedListIterable(this, f);
       }
       reduce(combine) {
         let length = this.length;
-        if (length === 0)
+        if (length == 0)
           throw IterableElementError.noElement();
         let value = this.elementAt(0);
         for (let i = 1; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           value = dart.dinvokef(combine, value, this.elementAt(i));
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return value;
       }
       fold(initialValue, combine) {
         let value = initialValue;
         let length = this.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           value = dart.dinvokef(combine, value, this.elementAt(i));
-          if (length !== this.length) {
+          if (length != this.length) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return value;
       }
       skip(count) {
         return new SubListIterable(this, count, null);
       }
       skipWhile(test) {
         return super.skipWhile(test);
@@ skipping 37 matching lines @@
   let _endIndex = Symbol('_endIndex');
   let _startIndex = Symbol('_startIndex');
   let SubListIterable$ = dart.generic(function(E) {
     class SubListIterable extends ListIterable$(E) {
       SubListIterable(iterable$, start$, endOrLength) {
         this[_iterable] = iterable$;
         this[_start] = start$;
         this[_endOrLength] = endOrLength;
         super.ListIterable();
         core.RangeError.checkNotNegative(this[_start], "start");
-        if (this[_endOrLength] !== null) {
+        if (this[_endOrLength] != null) {
           core.RangeError.checkNotNegative(this[_endOrLength], "end");
           if (dart.notNull(this[_start]) > dart.notNull(this[_endOrLength])) {
             throw new core.RangeError.range(this[_start], 0, this[_endOrLength], "start");
           }
         }
       }
       get [_endIndex]() {
         let length = this[_iterable].length;
-        if (this[_endOrLength] === null || dart.notNull(this[_endOrLength]) > dart.notNull(length))
+        if (this[_endOrLength] == null || dart.notNull(this[_endOrLength]) > dart.notNull(length))
           return length;
         return this[_endOrLength];
       }
       get [_startIndex]() {
         let length = this[_iterable].length;
         if (dart.notNull(this[_start]) > dart.notNull(length))
           return length;
         return this[_start];
       }
       get length() {
         let length = this[_iterable].length;
         if (dart.notNull(this[_start]) >= dart.notNull(length))
           return 0;
-        if (this[_endOrLength] === null || dart.notNull(this[_endOrLength]) >= dart.notNull(length)) {
+        if (this[_endOrLength] == null || dart.notNull(this[_endOrLength]) >= dart.notNull(length)) {
           return dart.notNull(length) - dart.notNull(this[_start]);
         }
         return dart.notNull(this[_endOrLength]) - dart.notNull(this[_start]);
       }
       elementAt(index) {
         let realIndex = dart.notNull(this[_startIndex]) + dart.notNull(index);
         if (dart.notNull(index) < 0 || dart.notNull(realIndex) >= dart.notNull(this[_endIndex])) {
           throw new core.RangeError.index(index, this, "index");
         }
         return this[_iterable].elementAt(realIndex);
       }
       skip(count) {
         core.RangeError.checkNotNegative(count, "count");
         let newStart = dart.notNull(this[_start]) + dart.notNull(count);
-        if (this[_endOrLength] !== null && dart.notNull(newStart) >= dart.notNull(this[_endOrLength])) {
+        if (this[_endOrLength] != null && dart.notNull(newStart) >= dart.notNull(this[_endOrLength])) {
           return new EmptyIterable();
         }
         return new SubListIterable(this[_iterable], newStart, this[_endOrLength]);
       }
       take(count) {
         core.RangeError.checkNotNegative(count, "count");
-        if (this[_endOrLength] === null) {
+        if (this[_endOrLength] == null) {
           return new SubListIterable(this[_iterable], this[_start], dart.notNull(this[_start]) + dart.notNull(count));
         } else {
           let newEnd = dart.notNull(this[_start]) + dart.notNull(count);
           if (dart.notNull(this[_endOrLength]) < dart.notNull(newEnd))
             return this;
           return new SubListIterable(this[_iterable], this[_start], newEnd);
         }
       }
       toList(opts) {
         let growable = opts && 'growable' in opts ? opts.growable : true;
         let start = this[_start];
         let end = this[_iterable].length;
-        if (this[_endOrLength] !== null && dart.notNull(this[_endOrLength]) < dart.notNull(end))
+        if (this[_endOrLength] != null && dart.notNull(this[_endOrLength]) < dart.notNull(end))
           end = this[_endOrLength];
         let length = dart.notNull(end) - dart.notNull(start);
         if (dart.notNull(length) < 0)
           length = 0;
         let result = growable ? ((_) => {
           _.length = length;
           return _;
         }).bind(this)(new core.List()) : new core.List(length);
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           result.set(i, this[_iterable].elementAt(dart.notNull(start) + dart.notNull(i)));
@@ skipping 15 matching lines @@
         this[_iterable] = iterable;
         this[_length] = iterable.length;
         this[_index] = 0;
         this[_current] = null;
       }
       get current() {
         return this[_current];
       }
       moveNext() {
         let length = this[_iterable].length;
-        if (this[_length] !== length) {
+        if (this[_length] != length) {
           throw new core.ConcurrentModificationError(this[_iterable]);
         }
         if (dart.notNull(this[_index]) >= dart.notNull(length)) {
           this[_current] = null;
           return false;
         }
         this[_current] = this[_iterable].elementAt(this[_index]);
         this[_index] = dart.notNull(this[_index]) + 1;
         return true;
       }
@@ skipping 151 matching lines @@
         this[_iterator] = iterator$;
         this[_f] = f$;
         this[_currentExpansion] = dart.as(new EmptyIterator(), core.Iterator$(T));
         this[_current] = null;
       }
       [_nextExpansion]() {}
       get current() {
         return this[_current];
       }
       moveNext() {
-        if (this[_currentExpansion] === null)
+        if (this[_currentExpansion] == null)
           return false;
         while (!dart.notNull(this[_currentExpansion].moveNext())) {
           this[_current] = null;
           if (this[_iterator].moveNext()) {
             this[_currentExpansion] = null;
             this[_currentExpansion] = dart.as(dart.dinvokef(this[_f], this[_iterator].current).iterator, core.Iterator$(T));
           } else {
             return false;
           }
         }
@@ skipping 251 matching lines @@
         return false;
       }
       every(test) {
         return true;
       }
       any(test) {
         return false;
       }
       firstWhere(test, opts) {
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       lastWhere(test, opts) {
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       singleWhere(test, opts) {
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       join(separator) {
         if (separator === void 0)
           separator = "";
         return "";
       }
       where(test) {
         return this;
@@ skipping 98 matching lines @@
         return initialValue;
       }
       static removeWhereList(list, test) {
         let retained = new core.List.from([]);
         let length = list.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           let element = list.get(i);
           if (!dart.notNull(dart.dinvokef(test, element))) {
             retained.add(element);
           }
-          if (length !== list.length) {
+          if (length != list.length) {
             throw new core.ConcurrentModificationError(list);
           }
         }
-        if (retained.length === length)
+        if (retained.length == length)
           return;
         list.length = retained.length;
         for (let i = 0; dart.notNull(i) < dart.notNull(retained.length); i = dart.notNull(i) + 1) {
           list.set(i, retained.get(i));
         }
       }
       static isEmpty(iterable) {
         return !dart.notNull(iterable.iterator.moveNext());
       }
       static first(iterable) {
@@ skipping 21 matching lines @@
         let result = it.current;
         if (it.moveNext())
           throw IterableElementError.tooMany();
         return result;
       }
       static firstWhere(iterable, test, orElse) {
         for (let element of iterable) {
           if (dart.dinvokef(test, element))
             return element;
         }
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       static lastWhere(iterable, test, orElse) {
         let result = null;
         let foundMatching = false;
         for (let element of iterable) {
           if (dart.dinvokef(test, element)) {
             result = element;
             foundMatching = true;
           }
         }
         if (foundMatching)
           return result;
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       static lastWhereList(list, test, orElse) {
         for (let i = dart.notNull(list.length) - 1; dart.notNull(i) >= 0; i = dart.notNull(i) - 1) {
           let element = list.get(i);
           if (dart.dinvokef(test, element))
             return element;
         }
-        if (orElse !== null)
+        if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       static singleWhere(iterable, test) {
         let result = null;
         let foundMatching = false;
         for (let element of iterable) {
           if (dart.dinvokef(test, element)) {
             if (foundMatching) {
               throw IterableElementError.tooMany();
             }
             result = element;
             foundMatching = true;
           }
         }
         if (foundMatching)
           return result;
         throw IterableElementError.noElement();
       }
       static elementAt(iterable, index) {
         if (!(typeof index == 'number'))
           throw new core.ArgumentError.notNull("index");
         core.RangeError.checkNotNegative(index, "index");
         let elementIndex = 0;
         for (let element of iterable) {
-          if (index === elementIndex)
+          if (index == elementIndex)
             return element;
           elementIndex = dart.notNull(elementIndex) + 1;
         }
         throw new core.RangeError.index(index, iterable, "index", null, elementIndex);
       }
       static join(iterable, separator) {
         if (separator === void 0)
           separator = null;
         let buffer = new core.StringBuffer();
         buffer.writeAll(iterable, separator);
         return buffer.toString();
       }
       static joinList(list, separator) {
         if (separator === void 0)
           separator = null;
         if (list.isEmpty)
           return "";
-        if (list.length === 1)
+        if (list.length == 1)
           return `${list.get(0)}`;
         let buffer = new core.StringBuffer();
         if (separator.isEmpty) {
           for (let i = 0; dart.notNull(i) < dart.notNull(list.length); i = dart.notNull(i) + 1) {
             buffer.write(list.get(i));
           }
         } else {
           buffer.write(list.get(0));
           for (let i = 1; dart.notNull(i) < dart.notNull(list.length); i = dart.notNull(i) + 1) {
             buffer.write(separator);
@@ skipping 23 matching lines @@
       skipList(list, n) {
         return new SubListIterable(dart.as(list, core.Iterable$(T)), n, null);
       }
       skipWhile(iterable, test) {
         return new SkipWhileIterable(dart.as(iterable, core.Iterable$(T)), dart.closureWrap(test, "(T) → bool"));
       }
       reversedList(list) {
         return new ReversedListIterable(dart.as(list, core.Iterable$(T)));
       }
       static sortList(list, compare) {
-        if (compare === null)
+        if (compare == null)
           compare = core.Comparable.compare;
         Sort.sort(list, compare);
       }
       static shuffleList(list, random) {
-        if (random === null)
+        if (random == null)
           random = new math.Random();
         let length = list.length;
         while (dart.notNull(length) > 1) {
           let pos = random.nextInt(length);
           length = 1;
           let tmp = list.get(length);
           list.set(length, list.get(pos));
           list.set(pos, tmp);
         }
       }
       static indexOfList(list, element, start) {
         return Lists.indexOf(list, element, start, list.length);
       }
       static lastIndexOfList(list, element, start) {
-        if (start === null)
+        if (start == null)
           start = dart.notNull(list.length) - 1;
         return Lists.lastIndexOf(list, element, start);
       }
       static [_rangeCheck](list, start, end) {
         core.RangeError.checkValidRange(start, end, list.length);
       }
       getRangeList(list, start, end) {
         IterableMixinWorkaround[_rangeCheck](list, start, end);
         return new SubListIterable(dart.as(list, core.Iterable$(T)), start, end);
       }
       static setRangeList(list, start, end, from, skipCount) {
         IterableMixinWorkaround[_rangeCheck](list, start, end);
         let length = dart.notNull(end) - dart.notNull(start);
-        if (length === 0)
+        if (length == 0)
           return;
         if (dart.notNull(skipCount) < 0)
           throw new core.ArgumentError(skipCount);
         let otherList = null;
         let otherStart = null;
         if (dart.is(from, core.List)) {
           otherList = from;
           otherStart = skipCount;
         } else {
           otherList = from.skip(skipCount).toList({growable: false});
           otherStart = 0;
         }
         if (dart.notNull(otherStart) + dart.notNull(length) > dart.notNull(otherList.length)) {
           throw IterableElementError.tooFew();
         }
         Lists.copy(otherList, otherStart, list, start, length);
       }
       static replaceRangeList(list, start, end, iterable) {
         IterableMixinWorkaround[_rangeCheck](list, start, end);
         if (!dart.is(iterable, EfficientLength)) {
           iterable = iterable.toList();
         }
         let removeLength = dart.notNull(end) - dart.notNull(start);
         let insertLength = iterable.length;
         if (dart.notNull(removeLength) >= dart.notNull(insertLength)) {
           let delta = dart.notNull(removeLength) - dart.notNull(insertLength);
           let insertEnd = dart.notNull(start) + dart.notNull(insertLength);
           let newEnd = dart.notNull(list.length) - dart.notNull(delta);
           list.setRange(start, insertEnd, iterable);
-          if (delta !== 0) {
+          if (delta != 0) {
             list.setRange(insertEnd, newEnd, list, end);
             list.length = newEnd;
           }
         } else {
           let delta = dart.notNull(insertLength) - dart.notNull(removeLength);
           let newLength = dart.notNull(list.length) + dart.notNull(delta);
           let insertEnd = dart.notNull(start) + dart.notNull(insertLength);
           list.length = newLength;
           list.setRange(insertEnd, newLength, list, end);
           list.setRange(start, insertEnd, iterable);
@@ skipping 247 matching lines @@
       containsValue(value) {
         return this[_values].contains(value);
       }
       containsKey(key) {
         return dart.notNull(typeof key == 'number') && dart.notNull(key) >= 0 && dart.notNull(key) < dart.notNull(this.length);
       }
       forEach(f) {
         let length = this[_values].length;
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           f(i, this[_values].get(i));
-          if (length !== this[_values].length) {
+          if (length != this[_values].length) {
             throw new core.ConcurrentModificationError(this[_values]);
           }
         }
       }
       set(key, value) {
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
       }
       putIfAbsent(key, ifAbsent) {
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
       }
@@ skipping 70 matching lines @@
           dst.set(j, src.get(i));
         }
       }
     }
     static areEqual(a, b) {
       if (core.identical(a, b))
         return true;
       if (!dart.notNull(dart.is(b, core.List)))
         return false;
       let length = a.length;
-      if (length !== dart.dload(b, 'length'))
+      if (!dart.equals(length, dart.dload(b, 'length')))
         return false;
       for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
         if (!dart.notNull(core.identical(a.get(i), dart.dindex(b, i))))
           return false;
       }
       return true;
     }
     static indexOf(a, element, startIndex, endIndex) {
       if (dart.notNull(startIndex) >= dart.notNull(a.length)) {
         return -1;
@@ skipping 131 matching lines @@
       }
       let pivot1 = el2;
       let pivot2 = el4;
       a.set(index1, el1);
       a.set(index3, el3);
       a.set(index5, el5);
       a.set(index2, a.get(left));
       a.set(index4, a.get(right));
       let less = dart.notNull(left) + 1;
       let great = dart.notNull(right) - 1;
-      let pivots_are_equal = dart.dinvokef(compare, pivot1, pivot2) === 0;
+      let pivots_are_equal = dart.dinvokef(compare, pivot1, pivot2) == 0;
       if (pivots_are_equal) {
         let pivot = pivot1;
         for (let k = less; dart.notNull(k) <= dart.notNull(great); k = dart.notNull(k) + 1) {
           let ak = a.get(k);
           let comp = dart.dinvokef(compare, ak, pivot);
-          if (comp === 0)
+          if (comp == 0)
             continue;
           if (dart.notNull(comp) < 0) {
-            if (k !== less) {
+            if (k != less) {
               a.set(k, a.get(less));
               a.set(less, ak);
             }
             less = dart.notNull(less) + 1;
           } else {
             while (true) {
               comp = dart.dinvokef(compare, a.get(great), pivot);
               if (dart.notNull(comp) > 0) {
                 great = dart.notNull(great) - 1;
                 continue;
               } else if (dart.notNull(comp) < 0) {
                 a.set(k, a.get(less));
                 a.set(((x) => less = dart.notNull(x) + 1, x)(less), a.get(great));
                 a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                 break;
               } else {
                 a.set(k, a.get(great));
                 a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                 break;
               }
             }
           }
         }
       } else {
         for (let k = less; dart.notNull(k) <= dart.notNull(great); k = dart.notNull(k) + 1) {
           let ak = a.get(k);
           let comp_pivot1 = dart.dinvokef(compare, ak, pivot1);
           if (dart.notNull(comp_pivot1) < 0) {
-            if (k !== less) {
+            if (k != less) {
               a.set(k, a.get(less));
               a.set(less, ak);
             }
             less = dart.notNull(less) + 1;
           } else {
             let comp_pivot2 = dart.dinvokef(compare, ak, pivot2);
             if (dart.notNull(comp_pivot2) > 0) {
               while (true) {
                 let comp = dart.dinvokef(compare, a.get(great), pivot2);
                 if (dart.notNull(comp) > 0) {
@@ skipping 21 matching lines @@
       a.set(left, a.get(dart.notNull(less) - 1));
       a.set(dart.notNull(less) - 1, pivot1);
       a.set(right, a.get(dart.notNull(great) + 1));
       a.set(dart.notNull(great) + 1, pivot2);
       Sort[_doSort](a, left, dart.notNull(less) - 2, compare);
       Sort[_doSort](a, dart.notNull(great) + 2, right, compare);
       if (pivots_are_equal) {
         return;
       }
       if (dart.notNull(less) < dart.notNull(index1) && dart.notNull(great) > dart.notNull(index5)) {
-        while (dart.dinvokef(compare, a.get(less), pivot1) === 0) {
+        while (dart.dinvokef(compare, a.get(less), pivot1) == 0) {
           less = dart.notNull(less) + 1;
         }
-        while (dart.dinvokef(compare, a.get(great), pivot2) === 0) {
+        while (dart.dinvokef(compare, a.get(great), pivot2) == 0) {
           great = dart.notNull(great) - 1;
         }
         for (let k = less; dart.notNull(k) <= dart.notNull(great); k = dart.notNull(k) + 1) {
           let ak = a.get(k);
           let comp_pivot1 = dart.dinvokef(compare, ak, pivot1);
-          if (comp_pivot1 === 0) {
-            if (k !== less) {
+          if (comp_pivot1 == 0) {
+            if (k != less) {
               a.set(k, a.get(less));
               a.set(less, ak);
             }
             less = dart.notNull(less) + 1;
           } else {
             let comp_pivot2 = dart.dinvokef(compare, ak, pivot2);
-            if (comp_pivot2 === 0) {
+            if (comp_pivot2 == 0) {
               while (true) {
                 let comp = dart.dinvokef(compare, a.get(great), pivot2);
-                if (comp === 0) {
+                if (comp == 0) {
                   great = dart.notNull(great) - 1;
                   if (dart.notNull(great) < dart.notNull(k))
                     break;
                   continue;
                 } else {
                   comp = dart.dinvokef(compare, a.get(great), pivot1);
                   if (dart.notNull(comp) < 0) {
                     a.set(k, a.get(less));
                     a.set(((x) => less = dart.notNull(x) + 1, x)(less), a.get(great));
                     a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
@@ skipping 132 matching lines @@
   exports.ReversedListIterable$ = ReversedListIterable$;
   exports.UnmodifiableListError = UnmodifiableListError;
   exports.NonGrowableListError = NonGrowableListError;
   exports.makeListFixedLength = makeListFixedLength;
   exports.Lists = Lists;
   exports.printToConsole = printToConsole;
   exports.Sort = Sort;
   exports.Symbol = Symbol;
   exports.POWERS_OF_TEN = POWERS_OF_TEN;
 })(_internal || (_internal = {}));