Support for double quoted strings

Changed array() to [] syntax.
Added variable in question to unknown variable exception.
Added getVar and getVars accessor functions.
Added getOperators and getFunctions accessor functions for completeness.
Extended all Exceptions off MathExecutorException.

12 files changed, 132 insertions, 34 deletions

diff --git a/src/NXP/Classes/Calculator.php b/src/NXP/Classes/Calculator.php
index 41e0d9f..bfa7015 100644
--- a/src/NXP/Classes/Calculator.php
+++ b/src/NXP/Classes/Calculator.php
@@ -13,6 +13,7 @@ namespace NXP\Classes;
 use NXP\Classes\Token\InterfaceOperator;
 use NXP\Classes\Token\TokenFunction;
 use NXP\Classes\Token\TokenNumber;
+use NXP\Classes\Token\TokenString;
 use NXP\Classes\Token\TokenVariable;
 use NXP\Exception\IncorrectExpressionException;
 use NXP\Exception\UnknownVariableException;
@@ -32,15 +33,18 @@ class Calculator
      */
     public function calculate($tokens, $variables)
     {
-        $stack = array();
+        $stack = [];
         foreach ($tokens as $token) {
             if ($token instanceof TokenNumber) {
                 array_push($stack, $token);
             }
+            if ($token instanceof TokenString) {
+                array_push($stack, $token);
+            }
             if ($token instanceof TokenVariable) {
                 $variable = $token->getValue();
                 if (!array_key_exists($variable, $variables)) {
-                    throw new UnknownVariableException();
+                    throw new UnknownVariableException($variable);
                 }
                 $value = $variables[$variable];
                 array_push($stack, new TokenNumber($value));
diff --git a/src/NXP/Classes/Lexer.php b/src/NXP/Classes/Lexer.php
index e541732..82b2c53 100644
--- a/src/NXP/Classes/Lexer.php
+++ b/src/NXP/Classes/Lexer.php
@@ -17,6 +17,7 @@ use NXP\Classes\Token\TokenLeftBracket;
 use NXP\Classes\Token\TokenNumber;
 use NXP\Classes\Token\TokenRightBracket;
 use NXP\Classes\Token\TokenVariable;
+use NXP\Classes\Token\TokenString;
 use NXP\Exception\IncorrectBracketsException;
 use NXP\Exception\IncorrectExpressionException;
 
@@ -42,7 +43,7 @@ class Lexer
      */
     public function stringToTokensStream($input)
     {
-        $matches = array();
+        $matches = [];
         preg_match_all($this->tokenFactory->getTokenParserRegex(), $input, $matches);
         $tokenFactory = $this->tokenFactory;
         $tokensStream = array_map(
@@ -62,10 +63,13 @@ class Lexer
      */
     public function buildReversePolishNotation($tokensStream)
     {
-        $output = array();
-        $stack = array();
+        $output = [];
+        $stack = [];
 
         foreach ($tokensStream as $token) {
+            if ($token instanceof TokenString) {
+                $output[] = $token;
+            }
             if ($token instanceof TokenNumber) {
                 $output[] = $token;
             }
diff --git a/src/NXP/Classes/Token/TokenFunction.php b/src/NXP/Classes/Token/TokenFunction.php
index 23f64bd..2ed8ace 100644
--- a/src/NXP/Classes/Token/TokenFunction.php
+++ b/src/NXP/Classes/Token/TokenFunction.php
@@ -29,7 +29,7 @@ class TokenFunction extends AbstractContainerToken implements InterfaceFunction
      */
     public function execute(&$stack)
     {
-        $args = array();
+        $args = [];
         list($places, $function) = $this->value;
         for ($i = 0; $i < $places; $i++) {
             array_push($args, array_pop($stack)->getValue());
diff --git a/src/NXP/Classes/Token/TokenString.php b/src/NXP/Classes/Token/TokenString.php
new file mode 100644
index 0000000..cab0711
--- /dev/null
+++ b/src/NXP/Classes/Token/TokenString.php
@@ -0,0 +1,25 @@
+<?php
+/**
+ * This file is part of the MathExecutor package
+ *
+ * (c) Alexander Kiryukhin
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code
+ */
+
+namespace NXP\Classes\Token;
+
+/**
+ * @author Bruce Wells <brucekwells@gmail.com>
+ */
+class TokenString extends AbstractContainerToken
+{
+    /**
+     * @return string
+     */
+    public static function getRegex()
+    {
+        return '"([^"]|"")*"';
+    }
+}
diff --git a/src/NXP/Classes/TokenFactory.php b/src/NXP/Classes/TokenFactory.php
index 19ba1cf..dbe6624 100644
--- a/src/NXP/Classes/TokenFactory.php
+++ b/src/NXP/Classes/TokenFactory.php
@@ -17,6 +17,7 @@ use NXP\Classes\Token\TokenLeftBracket;
 use NXP\Classes\Token\TokenNumber;
 use NXP\Classes\Token\TokenRightBracket;
 use NXP\Classes\Token\TokenVariable;
+use NXP\Classes\Token\TokenString;
 use NXP\Exception\UnknownFunctionException;
 use NXP\Exception\UnknownOperatorException;
 use NXP\Exception\UnknownTokenException;
@@ -31,24 +32,36 @@ class TokenFactory
      *
      * @var array
      */
-    protected $operators = array();
+    protected $operators = [];
 
     /**
      * Available functions
      *
      * @var array
      */
-    protected $functions = array();
+    protected $functions = [];
 
     /**
      * Add function
-     * @param $name
-     * @param $function
-     * @param $places
+     * @param string   $name
+     * @param callable $function
+     * @param int      $places
      */
-    public function addFunction($name, $function, $places = 1)
+    public function addFunction($name, callable $function, $places = 1)
     {
-        $this->functions[$name] = array($places, $function);
+        $this->functions[$name] = [$places, $function];
+    }
+
+
+    /**
+     * get functions
+     *
+     * @return array containing callback and places indexed by
+     *         function name
+     */
+    public function getFunctions()
+    {
+        return $this->functions;
     }
 
     /**
@@ -61,7 +74,7 @@ class TokenFactory
         $class = new \ReflectionClass($operatorClass);
 
         if (!in_array('NXP\Classes\Token\InterfaceToken', $class->getInterfaceNames())) {
-            throw new UnknownOperatorException;
+            throw new UnknownOperatorException($operatorClass);
         }
 
         $this->operators[] = $operatorClass;
@@ -69,13 +82,13 @@ class TokenFactory
     }
 
     /**
-     * Add variable
-     * @param string $name
-     * @param mixed  $value
+     * Get registered operators
+     *
+     * @return array of operator class names
      */
-    public function addVariable($name, $value)
+    public function getOperators()
     {
-
+        return $this->operators;
     }
 
     /**
@@ -89,8 +102,9 @@ class TokenFactory
         }
 
         return sprintf(
-            '/(%s)|([%s])|(%s)|(%s)|([%s%s%s])/i',
+            '/(%s)|(%s)|([%s])|(%s)|(%s)|([%s%s%s])/i',
             TokenNumber::getRegex(),
+            TokenString::getRegex(),
             $operatorsRegex,
             TokenFunction::getRegex(),
             TokenVariable::getRegex(),
@@ -119,6 +133,10 @@ class TokenFactory
             return new TokenRightBracket();
         }
 
+        if ($token[0] == '"') {
+            return new TokenString(str_replace('"', '', $token));
+        }
+
         if ($token == ',') {
             return new TokenComma();
         }
@@ -140,10 +158,10 @@ class TokenFactory
             if (isset($this->functions[$token])) {
                 return new TokenFunction($this->functions[$token]);
             } else {
-                throw new UnknownFunctionException();
+                throw new UnknownFunctionException($token);
             }
         }
 
-        throw new UnknownTokenException();
+        throw new UnknownTokenException($token);
     }
 }
diff --git a/src/NXP/Exception/IncorrectBracketsException.php b/src/NXP/Exception/IncorrectBracketsException.php
index e2aaed9..b3e8315 100644
--- a/src/NXP/Exception/IncorrectBracketsException.php
+++ b/src/NXP/Exception/IncorrectBracketsException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Alexander Kiryukhin <alexander@symdev.org>
  */
-class IncorrectBracketsException extends \Exception
+class IncorrectBracketsException extends MathExecutorException
 {
 }
diff --git a/src/NXP/Exception/IncorrectExpressionException.php b/src/NXP/Exception/IncorrectExpressionException.php
index ad5bc42..6f579c1 100644
--- a/src/NXP/Exception/IncorrectExpressionException.php
+++ b/src/NXP/Exception/IncorrectExpressionException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Vitaliy Zhuk <zhuk2205@gmail.com>
  */
-class IncorrectExpressionException extends \Exception
+class IncorrectExpressionException extends MathExecutorException
 {
 }
diff --git a/src/NXP/Exception/UnknownFunctionException.php b/src/NXP/Exception/UnknownFunctionException.php
index 5bb3658..e8ff0c0 100644
--- a/src/NXP/Exception/UnknownFunctionException.php
+++ b/src/NXP/Exception/UnknownFunctionException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Vitaliy Zhuk <zhuk2205@gmail.com>
  */
-class UnknownFunctionException extends \Exception
+class UnknownFunctionException extends MathExecutorException
 {
 }
diff --git a/src/NXP/Exception/UnknownOperatorException.php b/src/NXP/Exception/UnknownOperatorException.php
index b6617c3..acb4b98 100644
--- a/src/NXP/Exception/UnknownOperatorException.php
+++ b/src/NXP/Exception/UnknownOperatorException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Vitaliy Zhuk <zhuk2205@gmail.com>
  */
-class UnknownOperatorException extends \Exception
+class UnknownOperatorException extends MathExecutorException
 {
 }
diff --git a/src/NXP/Exception/UnknownTokenException.php b/src/NXP/Exception/UnknownTokenException.php
index b8a593f..bba28a4 100644
--- a/src/NXP/Exception/UnknownTokenException.php
+++ b/src/NXP/Exception/UnknownTokenException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Vitaliy Zhuk <zhuk2205@gmail.com>
  */
-class UnknownTokenException extends \Exception
+class UnknownTokenException extends MathExecutorException
 {
 }
diff --git a/src/NXP/Exception/UnknownVariableException.php b/src/NXP/Exception/UnknownVariableException.php
index 8de9493..8c215db 100644
--- a/src/NXP/Exception/UnknownVariableException.php
+++ b/src/NXP/Exception/UnknownVariableException.php
@@ -14,6 +14,6 @@ namespace NXP\Exception;
 /**
  * @author Alexander Kiryukhin <alexander@symdev.org>
  */
-class UnknownVariableException extends \Exception
+class UnknownVariableException extends MathExecutorException
 {
 }
diff --git a/src/NXP/MathExecutor.php b/src/NXP/MathExecutor.php
index 5cb4bca..56cefe5 100644
--- a/src/NXP/MathExecutor.php
+++ b/src/NXP/MathExecutor.php
@@ -15,6 +15,7 @@ use NXP\Classes\Calculator;
 use NXP\Classes\Lexer;
 use NXP\Classes\Token;
 use NXP\Classes\TokenFactory;
+use NXP\Exception\UnknownVariableException;
 
 /**
  * Class MathExecutor
@@ -27,7 +28,7 @@ class MathExecutor
      *
      * @var array
      */
-    private $variables = array();
+    private $variables = [];
 
     /**
      * @var TokenFactory
@@ -37,7 +38,7 @@ class MathExecutor
     /**
      * @var array
      */
-    private $cache = array();
+    private $cache = [];
 
     /**
      * Base math operators
@@ -75,10 +76,36 @@ class MathExecutor
         $this->tokenFactory->addFunction('max', 'max', 2);
         $this->tokenFactory->addFunction('avg', function($arg1, $arg2) { return ($arg1 + $arg2) / 2; }, 2);
 
-        $this->setVars(array(
+        $this->setVars([
             'pi' => 3.14159265359,
             'e'  => 2.71828182846
-        ));
+        ]);
+    }
+
+    /**
+     * Get all vars
+     *
+     * @return array
+     */
+    public function getVars()
+    {
+        return $this->variables;
+    }
+
+    /**
+     * Get a specific var
+     *
+     * @param  string        $variable
+     * @return integer|float
+     * @throws UnknownVariableException
+     */
+    public function getVar($variable)
+    {
+        if (! isset($this->variables[$variable])) {
+            throw new UnknownVariableException("Variable ({$variable}) not set");
+        }
+
+        return $this->variables[$variable];
     }
 
     /**
@@ -86,7 +113,6 @@ class MathExecutor
      *
      * @param  string        $variable
      * @param  integer|float $value
-     * @throws \Exception
      * @return MathExecutor
      */
     public function setVar($variable, $value)
@@ -134,7 +160,7 @@ class MathExecutor
      */
     public function removeVars()
     {
-        $this->variables = array();
+        $this->variables = [];
 
         return $this;
     }
@@ -153,6 +179,16 @@ class MathExecutor
     }
 
     /**
+     * Get all registered operators to executor
+     *
+     * @return array of operator class names
+     */
+    public function getOperators()
+    {
+        return $this->tokenFactory->getOperators();
+    }
+
+    /**
      * Add function to executor
      *
      * @param  string       $name     Name of function
@@ -168,6 +204,17 @@ class MathExecutor
     }
 
     /**
+     * Get all registered functions
+     *
+     * @return array containing callback and places indexed by
+     *         function name
+     */
+    public function getFunctions()
+    {
+        return $this->tokenFactory->getFunctions();
+    }
+
+    /**
      * Execute expression
      *
      * @param $expression