Get rid of for-of loops in fractions-common, see phetsims/tasks#972

js/common/EnumerationMap.js

@@ -23,10 +23,10 @@ define( require => {
       // @private {Enumeration}
       this._enumeration = enumeration;
 
-      for ( let entry of enumeration.VALUES ) {
+      enumeration.VALUES.forEach( entry => {
         assert && assert( this[ entry ] === undefined, 'Enumeration key override problem' );
         this[ entry ] = factory( entry );
-      }
+      } );
     }
 
     /**

js/common/model/PrimeFactorization.js

@@ -92,12 +92,12 @@ define( require => {
     binaryOperation( factorization, operation ) {
       const primes = _.uniq( [ ...this.factors, ...factorization.factors ].map( f => f.prime ) ).sort( ( a, b ) => a - b );
       const factors = [];
-      for ( let prime of primes ) {
+      primes.forEach( prime => {
         const order = operation( this.getOrder( prime ), factorization.getOrder( prime ) );
         if ( order ) {
           factors.push( new PrimeFactor( prime, order ) );
         }
-      }
+      } );
       return new PrimeFactorization( factors );
     }
 
@@ -164,7 +164,8 @@ define( require => {
      * @returns {boolean}
      */
     divides( factorization ) {
-      for ( let factor of this.factors ) {
+      for ( let i = 0; i < this.factors.length; i++ ) {
+        const factor = this.factors[ i ];
         if ( factor.order > factorization.getOrder( factor.prime ) ) {
           return false;
         }
@@ -236,7 +237,9 @@ define( require => {
 
       const factors = [];
 
-      for ( let prime of Primes.primes ) {
+      const primes = Primes.primes;
+      for ( let i = 0; i < primes.length; i++ ) {
+        const prime = primes[ i ];
         // A prime that is a divisor (not equal to our number) would be less than the max divisor
         if ( prime > maxDivisor ) { break; }
 

js/common/model/PrimeFactorizationTests.js

@@ -21,9 +21,9 @@ define( require => {
   QUnit.test( `Prime factorizations of everything up to ${MAX_NUMBER}`, assert => {
     for ( let n = 2; n < MAX_NUMBER; n++ ) {
       const factorization = PrimeFactorization.factor( n );
-      for ( let factor of factorization.factors ) {
+      factorization.factors.forEach( factor => {
         assert.ok( Primes.isPrime( factor.prime ), `Prime of factorization of ${n} is prime` );
-      }
+      } );
       assert.equal( n, factorization.number, `Prime factorization of ${n} is consistent` );
     }
   } );
@@ -62,9 +62,9 @@ define( require => {
       const factorization = PrimeFactorization.factor( a );
       const divisors = factorization.divisors;
 
-      for ( let divisor of divisors ) {
+      divisors.forEach( divisor => {
         assert.equal( a / divisor.number, factorization.divided( divisor ).number, `Division of ${a} divided by ${divisor.number}` );
-      }
+      } );
     }
   } );
 

js/game/model/CollectionFinder.js

@@ -78,9 +78,9 @@ define( require => {
         const constraintIndex = findMinConstraintIndex();
         const divisorDenominators = constraintDenominators[ constraintIndex ];
 
-        for ( let uncomputedDenominator of filterUncomputedDenominators( divisorDenominators ) ) {
+        filterUncomputedDenominators( divisorDenominators ).forEach( uncomputedDenominator => {
           entries.push( new Entry( uncomputedDenominator, lcm.divided( uncomputedDenominator ) ) );
-        }
+        } );
         for ( let i = 0; i < constraintDivisors.length; i++ ) {
           const divisor = constraintDivisors[ i ];
           const divisorDenominators = constraintDenominators[ i ];
@@ -95,9 +95,9 @@ define( require => {
         constraintDivisors.splice( constraintIndex, 1 );
         constraintDenominators.splice( constraintIndex, 1 );
       }
-      for ( let uncomputedDenominator of filterUncomputedDenominators( denominators ) ) {
+      filterUncomputedDenominators( denominators ).forEach( uncomputedDenominator => {
         entries.push( new Entry( uncomputedDenominator, lcm.divided( uncomputedDenominator ) ) );
-      }
+      } );
 
       // @private {Array.<Entry>}
       this.entries = entries;
@@ -182,7 +182,8 @@ define( require => {
             coefficients.push( coefficient );
 
             let constraintsSatisfied = true;
-            for ( let constraint of entry.constraints ) {
+            for ( let i = 0; i < entry.constraints.length; i++ ) {
+              const constraint = entry.constraints[ i ];
               if ( !constraint.satisfies( r, coefficients ) ) {
                 constraintsSatisfied = false;
                 break;

js/game/model/FractionChallenge.js

@@ -295,7 +295,8 @@ define( require => {
       // If we already have one out, don't look for more
       if ( groupArray.length >= 2 ) { return; }
 
-      for ( let groupStack of stackArray ) {
+      for ( let i = 0; i < stackArray.length; i++ ) {
+        const groupStack = stackArray[ i ];
         if ( !groupStack.isEmpty() ) {
           const group = groupStack.array.pop();
           group.clear();
@@ -560,7 +561,8 @@ define( require => {
 
         const possibilities = fractionPossibilities[ i ];
 
-        for ( let possibility of possibilities ) {
+        for ( let i = 0; i < possibilities.length; i++ ) {
+          const possibility = possibilities[ i ];
           if ( currentCollection.contains( possibility.total ) ) {
             currentCollection = currentCollection.minus( possibility.total );