Add negate() method to numeric types

README.md

@@ -125,6 +125,11 @@ All types support the TypeInterface:
 *  \__toString() - Magic toString method. Return value as a string
 *  \__invoke() - Proxy to get(), allows you to write $c() instead of $c->get()
 
+Numeric types, that is IntType, WholeIntType, NaturalIntType, FloatType, RationalType
+and ComplexType support the NumericTypeInterface which defines the method
+
+*  negate(): negate the number - NB Negation is will throw a \BadMethodCallException for WholeInt and NaturalInt types as they cannot be negative
+
 Additionally, the RationalType supports the RationalTypeInterface:
 
 *  setFromTypes(IntType $num, IntType $den, BoolType $reduce = null) - strict typed setter method
@@ -223,4 +228,6 @@ V1.0.2 Add conjugate method to complex type
 
 V1.0.3 Add modulus method to complex type
 
-V1.0.4 Fix RationalTypefactory::fromFloat not recognising zero
+V1.0.4 Fix RationalTypefactory::fromFloat not recognising zero
+
+V1.0.5 Add negate() method to numeric types

src/chippyash/Type/Number/Complex/ComplexType.php

@@ -168,4 +168,16 @@ public function setFromTypes(FloatType $real, FloatType $imaginary)
         return $this;
     }
 
+    /**
+     * Negates the number
+     * 
+     * @returns chippyash\Type\Number\Complex\ComplexType Fluent Interface
+     */
+    public function negate()
+    {
+        $this->real *= -1;
+        $this->imaginary *= -1;
+
+        return $this;
+    }    
 }

src/chippyash/Type/Number/FloatType.php

@@ -19,6 +19,18 @@
 class FloatType extends AbstractType implements NumericTypeInterface
 {
 
+    /**
+     * Negates the number
+     * 
+     * @returns chippyash\Type\Number\FloatType Fluent Interface
+     */
+    public function negate()
+    {
+        $this->value *= -1;
+
+        return $this;
+    }
+
     protected function typeOf($value)
     {
         return floatval($value);

src/chippyash/Type/Number/IntType.php

@@ -10,7 +10,7 @@
 
 namespace chippyash\Type\Number;
 
-use \chippyash\Type\AbstractType;
+use chippyash\Type\AbstractType;
 use chippyash\Type\Number\NumericTypeInterface;
 
 /**
@@ -19,6 +19,18 @@
 class IntType extends AbstractType implements NumericTypeInterface
 {
 
+    /**
+     * Negates the number
+     * 
+     * @returns chippyash\Type\Number\IntType Fluent Interface
+     */
+    public function negate()
+    {
+        $this->value *= -1;
+
+        return $this;
+    }
+
     protected function typeOf($value)
     {
         return intval($value);

src/chippyash/Type/Number/NaturalIntType.php

@@ -19,6 +19,16 @@
 class NaturalIntType extends IntType
 {
 
+    /**
+     * Negates the number
+     * 
+     * @throws \BadMethodCallException
+     */
+    public function negate()
+    {
+        throw new \BadMethodCallException('Negate not supported for Natural Int Types');
+    }
+
     protected function typeOf($value)
     {
         $v = intval($value);

src/chippyash/Type/Number/NumericTypeInterface.php

@@ -10,6 +10,14 @@
 namespace chippyash\Type\Number;
 
 /**
- * A dummy interface to mark numeric types
+ * A interface to mark numeric types
  */
-interface NumericTypeInterface {}
+interface NumericTypeInterface {
+
+    /**
+     * negates the number
+     * 
+     * @returns chippyash\Type\Number\NumericTypeInterface Fluent Interface
+     */
+    public function negate();
+}

src/chippyash/Type/Number/Rational/RationalType.php

@@ -107,6 +107,18 @@ public function __toString()
         return "{$this->num}/{$this->den}";
     }
 
+    /**
+     * Negates the number
+     * 
+     * @returns chippyash\Type\Number\Rational\RationalType Fluent Interface
+     */
+    public function negate()
+    {
+        $this->num *= -1;
+
+        return $this;
+    }
+
     /**
      * Reduce this number to it's lowest form
      */

src/chippyash/Type/Number/WholeIntType.php

@@ -19,6 +19,16 @@
 class WholeIntType extends IntType
 {
 
+    /**
+     * Negates the number
+     * 
+     * @throws \BadMethodCallException
+     */
+    public function negate()
+    {
+        throw new \BadMethodCallException('Negate not supported for Whole Int Types');
+    }
+
     protected function typeOf($value)
     {
         $v = intval($value);

test/src/chippyash/Type/Number/Complex/ComplexTypeTest.php

@@ -191,4 +191,10 @@ public function testCommutativeMultiplicationAttributeForModulus()
 
         $this->assertEquals($modc1mulc2(), $mod1() * $mod2());
     }
+
+    public function testCanNegateTheNumber()
+    {
+        $c = new ComplexType(new FloatType(1), new FloatType(2));
+        $this->assertEquals('-1-2i', $c->negate()->get());
+    }       
 }

test/src/chippyash/Type/Number/FloatTypeTest.php

@@ -17,4 +17,9 @@ public function testFloatTypeConvertsValuesToFloat()
         $this->assertEquals(0, $t->get());
     }
 
+    public function testCanNegateTheNumber()
+    {
+        $t = new FloatType(2.0);
+        $this->assertEquals(-2.0, $t->negate()->get());
+    }    
 }

test/src/chippyash/Type/Number/IntTypeTest.php

@@ -22,5 +22,11 @@ public function testIntTypeConvertsValuesToInteger()
         $this->assertInternalType('int', $t->get());
         $this->assertEquals(34, $t->get());
     }
+
+    public function testCanNegateTheNumber()
+    {
+        $t = new IntType(2);
+        $this->assertEquals(-2, $t->negate()->get());
+    }
 
 }

test/src/chippyash/Type/Number/NaturalIntTypeTest.php

@@ -29,4 +29,13 @@ public function testConstructNaturalIntWithIntegerLessThanOneThrowsException()
         $t = new NaturalIntType(0);
     }
 
+    /**
+     * @expectedException \BadMethodCallException
+     * @expectedExceptionMessage Negate not supported for Natural Int Types
+     */
+    public function testCannotNegateTheNumber()
+    {
+        $t = new NaturalIntType(12);
+        $t->negate();
+    }
 }

test/src/chippyash/Type/Number/Rational/RationalTypeTest.php

@@ -71,4 +71,10 @@ public function testGetReturnsFloat()
         $this->assertInternalType('float', $r->get());
         $this->assertEquals(0.5, $r->get());
     }
+
+    public function testCanNegateTheNumber()
+    {
+        $r = new RationalType(new IntType(1), new IntType(2));
+        $this->assertEquals(-0.5, $r->negate()->get());
+    }      
 }

test/src/chippyash/Type/Number/WholeIntTypeTest.php

@@ -32,4 +32,13 @@ public function testConstructWholeIntWithIntegerLessThanZeroThrowsException()
         $t = new WholeIntType(-1);
     }
 
+    /**
+     * @expectedException \BadMethodCallException
+     * @expectedExceptionMessage Negate not supported for Whole Int Types
+     */
+    public function testCannotNegateTheNumber()
+    {
+        $t = new WholeIntType(12);
+        $t->negate();
+    }    
 }