4 files changed, 30 insertions, 17 deletions
diff --git a/src/NXP/Classes/Calculator.php b/src/NXP/Classes/Calculator.php
index 4785a8f..a8f16af 100644
--- a/src/NXP/Classes/Calculator.php
+++ b/src/NXP/Classes/Calculator.php
@@ -44,7 +44,7 @@ class Calculator
     /**
      * Calculate array of tokens in reverse polish notation
      * @param Token[] $tokens
-     * @param array $variables
+     * @param array<string, float|string> $variables
      * @return mixed
      * @throws IncorrectExpressionException
      * @throws UnknownVariableException
@@ -68,7 +68,7 @@ class Calculator
                     throw new UnknownVariableException($variable);
                 }
 
-                $stack[] = new Token(Token::Literal, $value);
+                $stack[] = new Token(Token::Literal, $value, $variable);
             } elseif ($token->type === Token::Function) {
                 if (!array_key_exists($token->value, $this->functions)) {
                     throw new UnknownFunctionException($token->value);
diff --git a/src/NXP/Classes/CustomFunction.php b/src/NXP/Classes/CustomFunction.php
index f127ad2..6e4fdc5 100644
--- a/src/NXP/Classes/CustomFunction.php
+++ b/src/NXP/Classes/CustomFunction.php
@@ -44,6 +44,11 @@ class CustomFunction
         }
     }
 
+    /**
+     * @param array<Token> $stack
+     *
+     * @throws IncorrectNumberOfFunctionParametersException
+     */
     public function execute(array &$stack) : Token
     {
         if (count($stack) < $this->places) {
diff --git a/src/NXP/Classes/Operator.php b/src/NXP/Classes/Operator.php
index 00485bc..d9a70d7 100644
--- a/src/NXP/Classes/Operator.php
+++ b/src/NXP/Classes/Operator.php
@@ -24,7 +24,7 @@ class Operator
     public $priority;
 
     /**
-     * @var callable<\SplStack>
+     * @var callable(\SplStack)
      */
     public $function;
 
@@ -50,6 +50,11 @@ class Operator
         $this->places = $reflection->getNumberOfParameters();
     }
 
+    /**
+     * @param array<Token> $stack
+     *
+     * @throws IncorrectExpressionException
+     */
     public function execute(array &$stack) : Token
     {
         if (count($stack) < $this->places) {
diff --git a/src/NXP/Classes/Token.php b/src/NXP/Classes/Token.php
index 49bf741..e12315e 100644
--- a/src/NXP/Classes/Token.php
+++ b/src/NXP/Classes/Token.php
@@ -5,31 +5,34 @@ namespace NXP\Classes;
 
 class Token
 {
-    const Literal = "literal";
-    const Variable = "variable";
-    const Operator = "operator";
-    const LeftParenthesis = "LP";
-    const RightParenthesis = "RP";
-    const Function = "function";
-    const ParamSeparator = "separator";
-    const String = "string";
-    const Space = "space";
+    public const Literal = "literal";
+    public const Variable = "variable";
+    public const Operator = "operator";
+    public const LeftParenthesis = "LP";
+    public const RightParenthesis = "RP";
+    public const Function = "function";
+    public const ParamSeparator = "separator";
+    public const String = "string";
+    public const Space = "space";
 
+    /** @var self::* */
     public $type = self::Literal;
 
-    /**
-     * @var float|string
-     */
+    /** @var float|string */
     public $value;
 
+    /** @var string */
+    public $name;
+
     /**
      * Token constructor.
-     * @param string $type
+     * @param self::* $type
      * @param float|string $value
      */
-    public function __construct(string $type, $value)
+    public function __construct(string $type, $value, string $name = null)
     {
         $this->type = $type;
         $this->value = $value;
+        $this->name = $name;
     }
 }