File BinaryOperatorFlagVisitor.php has 697 lines of code (exceeds 250 allowed). Consider refactoring. Open
<?php
declare(strict_types=1);
namespace Phan\Analysis;Function checkInvalidArrayShapeCombination has a Cognitive Complexity of 36 (exceeds 5 allowed). Consider refactoring. Open
public static function checkInvalidArrayShapeCombination(
CodeBase $code_base,
Context $context,
Node $node,
UnionType $left,- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
BinaryOperatorFlagVisitor has 36 functions (exceeds 20 allowed). Consider refactoring. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operatingMethod computeIntOrFloatOperationResult has 105 lines of code (exceeds 25 allowed). Consider refactoring. Open
public static function computeIntOrFloatOperationResult(
Node $node,
UnionType $left,
UnionType $right
): UnionType {Method visitBinaryAdd has 84 lines of code (exceeds 25 allowed). Consider refactoring. Open
public function visitBinaryAdd(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(The class BinaryOperatorFlagVisitor has 30 public methods. Consider refactoring BinaryOperatorFlagVisitor to keep number of public methods under 10. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operating- Read upRead up
- Exclude checks
TooManyPublicMethods
Since: 0.1
A class with too many public methods is probably a good suspect for refactoring, in order to reduce its complexity and find a way to have more fine grained objects.
By default it ignores methods starting with 'get' or 'set'.
Example
Source https://phpmd.org/rules/codesize.html#toomanypublicmethods
The class BinaryOperatorFlagVisitor has an overall complexity of 157 which is very high. The configured complexity threshold is 50. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operating- Exclude checks
The class BinaryOperatorFlagVisitor has 35 non-getter- and setter-methods. Consider refactoring BinaryOperatorFlagVisitor to keep number of methods under 25. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operating- Read upRead up
- Exclude checks
TooManyMethods
Since: 0.1
A class with too many methods is probably a good suspect for refactoring, in order to reduce its complexity and find a way to have more fine grained objects.
By default it ignores methods starting with 'get' or 'set'.
The default was changed from 10 to 25 in PHPMD 2.3.
Example
Source https://phpmd.org/rules/codesize.html#toomanymethods
Function computeIntOrFloatOperationResult has a Cognitive Complexity of 22 (exceeds 5 allowed). Consider refactoring. Open
public static function computeIntOrFloatOperationResult(
Node $node,
UnionType $left,
UnionType $right
): UnionType {- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Function visitBinaryAdd has a Cognitive Complexity of 21 (exceeds 5 allowed). Consider refactoring. Open
public function visitBinaryAdd(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Method checkInvalidArrayShapeCombination has 64 lines of code (exceeds 25 allowed). Consider refactoring. Open
public static function checkInvalidArrayShapeCombination(
CodeBase $code_base,
Context $context,
Node $node,
UnionType $left,Consider simplifying this complex logical expression. Open
if ($left_is_array_like
&& !$right->hasArrayLike()
&& !$right_can_cast_to_array
&& !$right->isEmpty()
&& !$right->containsNullable()Method analyzeBinaryBitwiseCommon has 49 lines of code (exceeds 25 allowed). Consider refactoring. Open
private function analyzeBinaryBitwiseCommon(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,Method visitBinaryOpCommon has 46 lines of code (exceeds 25 allowed). Consider refactoring. Open
private function visitBinaryOpCommon(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,Method visit has 39 lines of code (exceeds 25 allowed). Consider refactoring. Open
public function visit(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,Method getTypeOfNumericArithmeticOp has 37 lines of code (exceeds 25 allowed). Consider refactoring. Open
private function getTypeOfNumericArithmeticOp(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(Function analyzeBinaryBitwiseCommon has a Cognitive Complexity of 12 (exceeds 5 allowed). Consider refactoring. Open
private function analyzeBinaryBitwiseCommon(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Method visitBinaryCoalesce has 34 lines of code (exceeds 25 allowed). Consider refactoring. Open
public function visitBinaryCoalesce(Node $node): UnionType
{
$left_node = $node->children['left'];
$left_type = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,Function visitBinaryCoalesce has a Cognitive Complexity of 10 (exceeds 5 allowed). Consider refactoring. Open
public function visitBinaryCoalesce(Node $node): UnionType
{
$left_node = $node->children['left'];
$left_type = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Method warnAboutInvalidUnionType has 6 arguments (exceeds 4 allowed). Consider refactoring. Open
Node $node,
Closure $is_valid_type,
UnionType $left,
UnionType $right,
string $left_issue_type,Function visit has a Cognitive Complexity of 8 (exceeds 5 allowed). Consider refactoring. Open
public function visit(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Method checkInvalidArrayShapeCombination has 5 arguments (exceeds 4 allowed). Consider refactoring. Open
CodeBase $code_base,
Context $context,
Node $node,
UnionType $left,
UnionType $rightAvoid too many return statements within this method. Open
return $make_literal_union_type(
is_int($value) ? LiteralIntType::instanceForValue($value, false)
: LiteralFloatType::instanceForValue($value, false),
$real_int_or_float
);Avoid too many return statements within this method. Open
return $probably_unknown_type;Avoid too many return statements within this method. Open
return UnionType::fromFullyQualifiedRealString('int|float');Avoid too many return statements within this method. Open
return $probably_unknown_type;Avoid too many return statements within this method. Open
return $probably_float_type;Avoid too many return statements within this method. Open
return FloatType::instance(false)->asPHPDocUnionType();Avoid too many return statements within this method. Open
return $int_or_float ?? ($int_or_float = UnionType::fromFullyQualifiedPHPDocString('int|float'));Avoid too many return statements within this method. Open
return $make_literal_union_type(
LiteralIntType::instanceForValue($value, false),
$real_int
);Avoid too many return statements within this method. Open
return $make_literal_union_type(
is_int($value) ? LiteralIntType::instanceForValue($value, false)
: LiteralFloatType::instanceForValue($value, false),
$real_int_or_float
);Avoid too many return statements within this method. Open
return $make_literal_union_type(
is_int($value) ? LiteralIntType::instanceForValue($value, false)
: LiteralFloatType::instanceForValue($value, false),
$real_int_or_float
);Avoid too many return statements within this method. Open
return $probably_array_type;Avoid too many return statements within this method. Open
return $right_type;Avoid too many return statements within this method. Open
return IntType::instance(false)->asPHPDocUnionType();Avoid too many return statements within this method. Open
return $make_literal_union_type(
is_int($value) ? LiteralIntType::instanceForValue($value, false)
: LiteralFloatType::instanceForValue($value, false),
$real_int_or_float
);Avoid too many return statements within this method. Open
return UnionType::fromFullyQualifiedPHPDocAndRealString(
$main_type,
'int|float'
);Avoid too many return statements within this method. Open
return;Avoid too many return statements within this method. Open
return FloatType::instance(false)->asRealUnionType();Avoid too many return statements within this method. Open
return $left_type->withUnionType($right_type)->asNormalizedTypes();Avoid too many return statements within this method. Open
return $make_literal_union_type(
LiteralIntType::instanceForValue($left_value ^ $right_value, false),
$real_int
);Avoid too many return statements within this method. Open
return FloatType::instance(false)->asRealUnionType();Avoid too many return statements within this method. Open
return $probably_int_or_float_type;Avoid too many return statements within this method. Open
return $make_literal_union_type(
is_int($value) ? LiteralIntType::instanceForValue($value, false)
: LiteralFloatType::instanceForValue($value, false),
$real_int_or_float
);Avoid too many return statements within this method. Open
return IntType::instance(false)->asRealUnionType();Avoid too many return statements within this method. Open
return $probably_int_or_float_type;Avoid too many return statements within this method. Open
return UnionType::fromFullyQualifiedPHPDocAndRealString('int', 'int|string');Avoid too many return statements within this method. Open
return ArrayType::combineArrayTypesOverriding($left, $right, false);Function warnAboutInvalidUnionType has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
private function warnAboutInvalidUnionType(
Node $node,
Closure $is_valid_type,
UnionType $left,
UnionType $right,- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
The method computeIntOrFloatOperationResult() has 127 lines of code. Current threshold is set to 100. Avoid really long methods. Open
public static function computeIntOrFloatOperationResult(
Node $node,
UnionType $left,
UnionType $right
): UnionType {- Exclude checks
The method visitBinaryAdd() has 106 lines of code. Current threshold is set to 100. Avoid really long methods. Open
public function visitBinaryAdd(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(- Exclude checks
The method computeIntOrFloatOperationResult() has an NPath complexity of 6360. The configured NPath complexity threshold is 200. Open
public static function computeIntOrFloatOperationResult(
Node $node,
UnionType $left,
UnionType $right
): UnionType {- Read upRead up
- Exclude checks
NPathComplexity
Since: 0.1
The NPath complexity of a method is the number of acyclic execution paths through that method. A threshold of 200 is generally considered the point where measures should be taken to reduce complexity.
Example
class Foo {
function bar() {
// lots of complicated code
}
}Source https://phpmd.org/rules/codesize.html#npathcomplexity
The method checkInvalidArrayShapeCombination() has an NPath complexity of 4104. The configured NPath complexity threshold is 200. Open
public static function checkInvalidArrayShapeCombination(
CodeBase $code_base,
Context $context,
Node $node,
UnionType $left,- Read upRead up
- Exclude checks
NPathComplexity
Since: 0.1
The NPath complexity of a method is the number of acyclic execution paths through that method. A threshold of 200 is generally considered the point where measures should be taken to reduce complexity.
Example
class Foo {
function bar() {
// lots of complicated code
}
}Source https://phpmd.org/rules/codesize.html#npathcomplexity
The method visitBinaryAdd() has an NPath complexity of 2040. The configured NPath complexity threshold is 200. Open
public function visitBinaryAdd(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(- Read upRead up
- Exclude checks
NPathComplexity
Since: 0.1
The NPath complexity of a method is the number of acyclic execution paths through that method. A threshold of 200 is generally considered the point where measures should be taken to reduce complexity.
Example
class Foo {
function bar() {
// lots of complicated code
}
}Source https://phpmd.org/rules/codesize.html#npathcomplexity
The class BinaryOperatorFlagVisitor has 1023 lines of code. Current threshold is 1000. Avoid really long classes. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operating- Exclude checks
The method checkInvalidArrayShapeCombination() has a Cyclomatic Complexity of 19. The configured cyclomatic complexity threshold is 10. Open
public static function checkInvalidArrayShapeCombination(
CodeBase $code_base,
Context $context,
Node $node,
UnionType $left,- Read upRead up
- Exclude checks
CyclomaticComplexity
Since: 0.1
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are 'if', 'while', 'for', and 'case labels'. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
Example
// Cyclomatic Complexity = 11
class Foo {
1 public function example() {
2 if ($a == $b) {
3 if ($a1 == $b1) {
fiddle();
4 } elseif ($a2 == $b2) {
fiddle();
} else {
fiddle();
}
5 } elseif ($c == $d) {
6 while ($c == $d) {
fiddle();
}
7 } elseif ($e == $f) {
8 for ($n = 0; $n < $h; $n++) {
fiddle();
}
} else {
switch ($z) {
9 case 1:
fiddle();
break;
10 case 2:
fiddle();
break;
11 case 3:
fiddle();
break;
default:
fiddle();
break;
}
}
}
}Source https://phpmd.org/rules/codesize.html#cyclomaticcomplexity
The method visitBinaryOpCommon() has a Cyclomatic Complexity of 13. The configured cyclomatic complexity threshold is 10. Open
private function visitBinaryOpCommon(Node $node): UnionType
{
$left = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,
$this->context,- Read upRead up
- Exclude checks
CyclomaticComplexity
Since: 0.1
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are 'if', 'while', 'for', and 'case labels'. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
Example
// Cyclomatic Complexity = 11
class Foo {
1 public function example() {
2 if ($a == $b) {
3 if ($a1 == $b1) {
fiddle();
4 } elseif ($a2 == $b2) {
fiddle();
} else {
fiddle();
}
5 } elseif ($c == $d) {
6 while ($c == $d) {
fiddle();
}
7 } elseif ($e == $f) {
8 for ($n = 0; $n < $h; $n++) {
fiddle();
}
} else {
switch ($z) {
9 case 1:
fiddle();
break;
10 case 2:
fiddle();
break;
11 case 3:
fiddle();
break;
default:
fiddle();
break;
}
}
}
}Source https://phpmd.org/rules/codesize.html#cyclomaticcomplexity
The method visitBinaryAdd() has a Cyclomatic Complexity of 24. The configured cyclomatic complexity threshold is 10. Open
public function visitBinaryAdd(Node $node): UnionType
{
$code_base = $this->code_base;
$context = $this->context;
$left = UnionTypeVisitor::unionTypeFromNode(- Read upRead up
- Exclude checks
CyclomaticComplexity
Since: 0.1
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are 'if', 'while', 'for', and 'case labels'. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
Example
// Cyclomatic Complexity = 11
class Foo {
1 public function example() {
2 if ($a == $b) {
3 if ($a1 == $b1) {
fiddle();
4 } elseif ($a2 == $b2) {
fiddle();
} else {
fiddle();
}
5 } elseif ($c == $d) {
6 while ($c == $d) {
fiddle();
}
7 } elseif ($e == $f) {
8 for ($n = 0; $n < $h; $n++) {
fiddle();
}
} else {
switch ($z) {
9 case 1:
fiddle();
break;
10 case 2:
fiddle();
break;
11 case 3:
fiddle();
break;
default:
fiddle();
break;
}
}
}
}Source https://phpmd.org/rules/codesize.html#cyclomaticcomplexity
The method visitBinaryCoalesce() has a Cyclomatic Complexity of 11. The configured cyclomatic complexity threshold is 10. Open
public function visitBinaryCoalesce(Node $node): UnionType
{
$left_node = $node->children['left'];
$left_type = UnionTypeVisitor::unionTypeFromNode(
$this->code_base,- Read upRead up
- Exclude checks
CyclomaticComplexity
Since: 0.1
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are 'if', 'while', 'for', and 'case labels'. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
Example
// Cyclomatic Complexity = 11
class Foo {
1 public function example() {
2 if ($a == $b) {
3 if ($a1 == $b1) {
fiddle();
4 } elseif ($a2 == $b2) {
fiddle();
} else {
fiddle();
}
5 } elseif ($c == $d) {
6 while ($c == $d) {
fiddle();
}
7 } elseif ($e == $f) {
8 for ($n = 0; $n < $h; $n++) {
fiddle();
}
} else {
switch ($z) {
9 case 1:
fiddle();
break;
10 case 2:
fiddle();
break;
11 case 3:
fiddle();
break;
default:
fiddle();
break;
}
}
}
}Source https://phpmd.org/rules/codesize.html#cyclomaticcomplexity
The method computeIntOrFloatOperationResult() has a Cyclomatic Complexity of 30. The configured cyclomatic complexity threshold is 10. Open
public static function computeIntOrFloatOperationResult(
Node $node,
UnionType $left,
UnionType $right
): UnionType {- Read upRead up
- Exclude checks
CyclomaticComplexity
Since: 0.1
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are 'if', 'while', 'for', and 'case labels'. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
Example
// Cyclomatic Complexity = 11
class Foo {
1 public function example() {
2 if ($a == $b) {
3 if ($a1 == $b1) {
fiddle();
4 } elseif ($a2 == $b2) {
fiddle();
} else {
fiddle();
}
5 } elseif ($c == $d) {
6 while ($c == $d) {
fiddle();
}
7 } elseif ($e == $f) {
8 for ($n = 0; $n < $h; $n++) {
fiddle();
}
} else {
switch ($z) {
9 case 1:
fiddle();
break;
10 case 2:
fiddle();
break;
11 case 3:
fiddle();
break;
default:
fiddle();
break;
}
}
}
}Source https://phpmd.org/rules/codesize.html#cyclomaticcomplexity
The class BinaryOperatorFlagVisitor has a coupling between objects value of 24. Consider to reduce the number of dependencies under 13. Open
final class BinaryOperatorFlagVisitor extends FlagVisitorImplementation
{
/**
* @var CodeBase The code base within which we're operating- Read upRead up
- Exclude checks
CouplingBetweenObjects
Since: 1.1.0
A class with too many dependencies has negative impacts on several quality aspects of a class. This includes quality criteria like stability, maintainability and understandability
Example
class Foo {
/**
* @var \foo\bar\X
*/
private $x = null;
/**
* @var \foo\bar\Y
*/
private $y = null;
/**
* @var \foo\bar\Z
*/
private $z = null;
public function setFoo(\Foo $foo) {}
public function setBar(\Bar $bar) {}
public function setBaz(\Baz $baz) {}
/**
* @return \SplObjectStorage
* @throws \OutOfRangeException
* @throws \InvalidArgumentException
* @throws \ErrorException
*/
public function process(\Iterator $it) {}
// ...
}Source https://phpmd.org/rules/design.html#couplingbetweenobjects
Identical blocks of code found in 2 locations. Consider refactoring. Open
private function warnAboutInvalidUnionType(
Node $node,
Closure $is_valid_type,
UnionType $left,
UnionType $right,- Read upRead up
Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 168.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication's documentation for more information about tuning the mass threshold in your .codeclimate.yml.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76