Rector standards slowly being applied. PHP Version first.

src/TrueSkill/Factors/GaussianGreaterThanFactor.php

@@ -16,7 +16,7 @@ use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
  */
 class GaussianGreaterThanFactor extends GaussianFactor
 {
-    private float $epsilon;
+    private readonly float $epsilon;
 
     public function __construct(float $epsilon, Variable $variable)
     {

src/TrueSkill/Factors/GaussianLikelihoodFactor.php

@@ -17,7 +17,7 @@ use Exception;
  */
 class GaussianLikelihoodFactor extends GaussianFactor
 {
-    private float $precision;
+    private readonly float $precision;
 
     public function __construct(float $betaSquared, Variable $variable1, Variable $variable2)
     {

src/TrueSkill/Factors/GaussianPriorFactor.php

@@ -15,7 +15,7 @@ use DNW\Skills\Numerics\GaussianDistribution;
  */
 class GaussianPriorFactor extends GaussianFactor
 {
-    private GaussianDistribution $newMessage;
+    private readonly GaussianDistribution $newMessage;
 
     public function __construct(float $mean, float $variance, Variable $variable)
     {

src/TrueSkill/Factors/GaussianWithinFactor.php

@@ -16,7 +16,7 @@ use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
  */
 class GaussianWithinFactor extends GaussianFactor
 {
-    private float $epsilon;
+    private readonly float $epsilon;
 
     public function __construct(float $epsilon, Variable $variable)
     {

src/TrueSkill/Layers/TeamDifferencesComparisonLayer.php

@@ -11,7 +11,7 @@ use DNW\Skills\TrueSkill\TrueSkillFactorGraph;
 
 class TeamDifferencesComparisonLayer extends TrueSkillFactorGraphLayer
 {
-    private float $epsilon;
+    private readonly float $epsilon;
 
     /**
      * @param int[] $teamRanks

src/TrueSkill/TrueSkillFactorGraph.php

@@ -28,7 +28,7 @@ class TrueSkillFactorGraph extends FactorGraph
      */
     private array $layers;
 
-    private PlayerPriorValuesToSkillsLayer $priorLayer;
+    private readonly PlayerPriorValuesToSkillsLayer $priorLayer;
 
     /**
      * @param GameInfo $gameInfo  Parameters for the game.