Corpus-NZ/Code-Syntax-Expanded · Datasets at Hugging Face

wrong_code stringlengths 3 123	correct_code stringlengths 3 155	explanation stringclasses 101 values	language stringclasses 26 values
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
my @arr = (35,29,11);	my @arr = (35,29,11);	Correct.	Perl
b > 36 & a < 28	b > 36 and a < 28	Use 'and' not '&'.	Python
var bar int = 'result'	var bar string = 'result'	Type mismatch.	Go
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
class Product {{ int num; }};	class Product {{ public: int num; }};	Make public.	C++
def handle(): print('message')	def handle(): print('message')	Indent function body.	Python
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
'data' + 4	'data' + 4.to_s	Convert int.	Ruby
const index;	const index = 59;	Initialize const.	JavaScript
if (index = 45) {}	if (index == 45) {}	Use ==.	Dart
println('result')	println("result")	Double quotes.	Scala
INSERT INTO orders VALUES ('message',5)	INSERT INTO orders (age, email) VALUES ('message',5);	Specify columns.	SQL
while read line; do echo $line; done < log.txt	while read line; do echo $line; done < log.txt	Correct.	Shell
let list=vec![47,92,23]; let primary=&list[0]; list.push(52);	let mut list=vec![47,92,23]; let primary=list[0]; list.push(52);	Copy instead of reference.	Rust
int* p = nullptr; *p=5;	int* p = new int; *p=5;	Allocate memory.	C++
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
Write-Host 'result'	Write-Host 'result'	Correct.	PowerShell
<ul><li>hello<li>data</ul>	<ul><li>hello</li><li>data</li></ul>	Close li.	HTML
<table><tr><td>world<td>test</tr></table>	<table><tr><td>world</td><td>test</td></tr></table>	Close td.	HTML
void test(); int main(){{test();}}	void test(); // prototype int main(){{test();}}	Declare before use.	C++
if y = 49	if y == 49	Use ==.	Ruby
print('world')	print('world')	Correct.	R
compute	compute()	Add parentheses.	Kotlin
<div><p>hello</div></p>	<div><p>hello</p></div>	Nest properly.	HTML
let str1 = String::from("info"); let s2 = str1; println!("{{}}", str1);	let str1 = String::from("info"); let s2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
String a = 'info';	String a = "info";	Double quotes.	Java
let mut item=78; let ref1=&mut item; let r2=&mut item;	let mut item=78; {{ let ref1=&mut item; }} let r2=&mut item;	Only one mutable borrow.	Rust
fmt.Println 'result'	fmt.Println('result')	Missing parentheses.	Go
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
def test puts 'info' end	def test puts 'info' end	Correct.	Ruby
echo 'world'	echo 'world';	Add semicolon.	PHP
val num = 'hello'	val num = "hello"	Double quotes.	Kotlin
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
function baz() {{ return {{key:'hello'}} }}	function baz() {{ return {{key:'hello'}}; }}	Return object on same line.	JavaScript
try {{ throw 'test'; }} catch(e) {{}}	try {{ throw new Error('test'); }} catch(e) {{}}	Throw Error objects.	JavaScript
x := 21	x := 21	Correct.	Go
if x = 4:	if x == 4:	Use == for comparison.	Python
if (temp = 88)	if (temp == 88)	Use ==.	R
var x int	var x int	Correct.	Go
if b > 74 puts 'hello'	if b > 74 puts 'hello' end	Add 'end'.	Ruby
function bar(bar:string){{return bar;}} bar(33);	function bar(bar:string){{return bar;}} bar('data');	Pass correct type.	TypeScript
function handle(index) print(index) end	function handle(index) print(index) end	Correct.	Lua
int items[79]; items[79]=5;	int items[79]; if(79<79){{}} else items[79]=5;	Bounds check.	C++
Post.save();	Post.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
<person name='message'/>	<person name="message"/>	Double quotes.	XML
SELECT name role FROM products;	SELECT name, role FROM products;	Add comma.	SQL
assert val > 71	assert val > 71	Correct.	Python
{{"status":"info",}}	{{"status":"info"}}	Remove trailing comma.	JSON
<person age=21>	<person age="21">	Quote attribute.	XML
$items[4]	if ($items.Count -gt 4) {{ $items[4] }}	Check bounds.	PowerShell
JOIN profiles ON products.id = profiles.id	JOIN profiles ON products.id = profiles.id	Correct.	SQL
fn foo() -> i32 {{ 43 }}	fn foo() -> i32 {{ 43 }}	Correct.	Rust
let val: number = 'result';	let val: string = 'result';	Fix type.	TypeScript
def compute(b): return b + 1	def compute(b): return b + 1	Correct.	Python
if (foo = 22)	if (foo == 22)	Use ==.	Scala
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
x := 100	x := 100	Correct.	Go
{{'status':'value'}}	{{"status":"value"}}	Use double quotes.	JSON
values.forEach(function(num) {{ console.log(num); }})	values.forEach((num) => {{ console.log(num); }})	Arrow functions are cleaner.	JavaScript
if ($z = 71) {{}}	if ($z -eq 71) {{}}	Use -eq.	PowerShell
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
<entry><age>hello</age><name>99</name></entry	<entry><age>hello</age><name>99</name></entry>	Add closing >.	XML
if (c) console.log('yes') else console.log('no')	if (c) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
Write-Host 'hello'	Write-Host 'hello'	Correct.	PowerShell
$a = 9; if ($a = 9) {{}}	$a = 9; if ($a == 9) {{}}	Use ==.	PHP
'value' + 16	'value' + 16.to_s	Convert int.	Ruby
[x*x for x in data if x > 74]	[x*x for x in data if x > 74]	Correct list comprehension.	Python
local b = 87	local b = 87	Correct.	Lua
let index: Int = 'info'	let index: String = 'info'	Fix type.	Swift
fn baz() -> i32 {{ 16 }}	fn baz() -> i32 {{ 16 }}	Correct.	Rust
y = test	y = 'test'	Quote strings.	Python
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
print 'test'	print('test')	print needs parentheses.	Python
void main() {{ print('value') }}	void main() {{ print('value'); }}	Add semicolon.	Dart
<?php // code ?>	<?php // code ?>	Correct.	PHP
my @arr = (62,72,15);	my @arr = (62,72,15);	Correct.	Perl
for b in range(72) print(b)	for b in range(72): print(b)	Colon after for.	Python
<div color=#fff>	<div style='color:#fff;'>	Use style attribute.	CSS
if item = 39	if item == 39	Use ==.	Go
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
class Product {{ int a; }} obj.a=5;	class Product {{ public int a; }} obj.a=5;	Make field public.	Java
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
<center>test</center>	<div style='text-align:center;'>test</div>	Use CSS.	HTML
let a = 'output'	let a = "output"	Double quotes.	Swift
data[28]	if (length(data) >= 28) data[28]	Check length.	R
match count {{ 1 => {{}} }}	match count {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
[29, 48, 27	[29, 48, 27]	Close bracket.	Ruby
h1 {{ font-size:70px color:green; }}	h1 {{ font-size:70px; color:green; }}	Add semicolon.	CSS
val val: Int = 'test'	val val: String = 'test'	Fix type.	Kotlin
if (index = 45) {{}}	if (index === 45) {{}}	Use === for equality.	JavaScript
val temp = 49; temp = 91	var temp = 49; temp = 91	Use var for reassignment.	Scala
name: info value: hello,	name: info value: hello	Remove comma.	YAML
class Person def method end end	class Person def method end end	Correct.	Ruby
values[10]	if (values.indices.contains(10)) values[10]	Check index.	Kotlin
int arr[21]; arr[21]=5;	int arr[21]; if(21<21){{}} else arr[21]=5;	Bounds check.	C++

public static void main(String[] args) {{}}

Correct.

Java

my @arr = (35,29,11);

Correct.

Perl

b > 36 & a < 28

b > 36 and a < 28

Use 'and' not '&'.

Python

var bar int = 'result'

var bar string = 'result'

Type mismatch.

Go

Add rel for security.

HTML

class Product {{ int num; }};

class Product {{ public: int num; }};

Make public.

C++

def handle(): print('message')

Indent function body.

Python

$x = 5; if ($x -eq 5) { Write-Host 'yes' }

Correct.

PowerShell

'data' + 4

'data' + 4.to_s

Convert int.

Ruby

const index;

const index = 59;

Initialize const.

JavaScript

if (index = 45) {}

if (index == 45) {}

Use ==.

Dart

println('result')

println("result")

Double quotes.

Scala

INSERT INTO orders VALUES ('message',5)

INSERT INTO orders (age, email) VALUES ('message',5);

Specify columns.

SQL

while read line; do echo $line; done < log.txt

Correct.

Shell

let list=vec![47,92,23]; let primary=&list[0]; list.push(52);

let mut list=vec![47,92,23]; let primary=list[0]; list.push(52);

Copy instead of reference.

Rust

int* p = nullptr; *p=5;

int* p = new int; *p=5;

Allocate memory.

C++

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

Write-Host 'result'

Correct.

PowerShell

<ul><li>hello<li>data</ul>

<ul><li>hello</li><li>data</li></ul>

Close li.

HTML

<table><tr><td>world<td>test</tr></table>

<table><tr><td>world</td><td>test</td></tr></table>

Close td.

HTML

void test(); int main(){{test();}}

void test(); // prototype int main(){{test();}}

Declare before use.

C++

if y = 49

if y == 49

Use ==.

Ruby

print('world')

Correct.

R

compute

compute()

Add parentheses.

Kotlin

<div><p>hello</div></p>

<div><p>hello</p></div>

Nest properly.

HTML

let str1 = String::from("info"); let s2 = str1; println!("{{}}", str1);

let str1 = String::from("info"); let s2 = str1.clone(); println!("{{}}", str1);

Clone to avoid move.

Rust

String a = 'info';

String a = "info";

Double quotes.

Java

let mut item=78; let ref1=&mut item; let r2=&mut item;

let mut item=78; {{ let ref1=&mut item; }} let r2=&mut item;

Only one mutable borrow.

Rust

fmt.Println 'result'

fmt.Println('result')

Missing parentheses.

Go

for i in $(ls); do echo $i; done

Correct.

Shell

def test puts 'info' end

Correct.

Ruby

echo 'world'

echo 'world';

Add semicolon.

PHP

val num = 'hello'

val num = "hello"

Double quotes.

Kotlin

ArrayList list = new ArrayList();

ArrayList<String> list = new ArrayList<>();

Use generics.

Java

int x; System.out.println(x);

int x = 0; System.out.println(x);

Initialize variable.

Java

@media screen {{ body {{}} }}

Correct.

CSS

function baz() {{ return {{key:'hello'}} }}

function baz() {{ return {{key:'hello'}}; }}

Return object on same line.

JavaScript

try {{ throw 'test'; }} catch(e) {{}}

try {{ throw new Error('test'); }} catch(e) {{}}

Throw Error objects.

JavaScript

x := 21

Correct.

Go

if x = 4:

if x == 4:

Use == for comparison.

Python

if (temp = 88)

if (temp == 88)

Use ==.

R

var x int

Correct.

Go

if b > 74 puts 'hello'

if b > 74 puts 'hello' end

Add 'end'.

Ruby

function bar(bar:string){{return bar;}} bar(33);

function bar(bar:string){{return bar;}} bar('data');

Pass correct type.

TypeScript

function handle(index) print(index) end

Correct.

Lua

int items[79]; items[79]=5;

int items[79]; if(79<79){{}} else items[79]=5;

Bounds check.

C++

Post.save();

Post.save().then(()=>{{}}).catch(err=>{{}});

Handle promise.

Node.js

Double quotes.

XML

SELECT name role FROM products;

SELECT name, role FROM products;

Add comma.

SQL

assert val > 71

Correct.

Python

Remove trailing comma.

JSON

Quote attribute.

XML

$items[4]

if ($items.Count -gt 4) {{ $items[4] }}

Check bounds.

PowerShell

JOIN profiles ON products.id = profiles.id

Correct.

SQL

fn foo() -> i32 {{ 43 }}

Correct.

Rust

let val: number = 'result';

let val: string = 'result';

Fix type.

TypeScript

def compute(b): return b + 1

Correct.

Python

if (foo = 22)

if (foo == 22)

Use ==.

Scala

public static void main(String[] args) {{}}

Correct.

Java

x := 100

Correct.

Go

Use double quotes.

JSON

values.forEach(function(num) {{ console.log(num); }})

values.forEach((num) => {{ console.log(num); }})

Arrow functions are cleaner.

JavaScript

if ($z = 71) {{}}

if ($z -eq 71) {{}}

Use -eq.

PowerShell

try {{ throw 'hello'; }} catch(e) {{}}

try {{ throw new Error('hello'); }} catch(e) {{}}

Throw Error objects.

JavaScript

<entry><age>hello</age><name>99</name></entry

<entry><age>hello</age><name>99</name></entry>

Add closing >.

XML

if (c) console.log('yes') else console.log('no')

if (c) console.log('yes'); else console.log('no');

Missing semicolon.

JavaScript

Write-Host 'hello'

Correct.

PowerShell

$a = 9; if ($a = 9) {{}}

$a = 9; if ($a == 9) {{}}

Use ==.

PHP

'value' + 16

'value' + 16.to_s

Convert int.

Ruby

[x*x for x in data if x > 74]

Correct list comprehension.

Python

local b = 87

Correct.

Lua

let index: Int = 'info'

let index: String = 'info'

Fix type.

Swift

fn baz() -> i32 {{ 16 }}

Correct.

Rust

y = test

y = 'test'

Quote strings.

Python

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

print 'test'

print('test')

print needs parentheses.

Python

void main() {{ print('value') }}

void main() {{ print('value'); }}

Add semicolon.

Dart

<?php // code ?>

Correct.

PHP

my @arr = (62,72,15);

Correct.

Perl

for b in range(72) print(b)

for b in range(72): print(b)

Colon after for.

Python

Use style attribute.

CSS

if item = 39

if item == 39

Use ==.

Go

x <- 5; if (x > 3) print('large')

Correct.

R

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

type MyType = string | number; let x: MyType = true;

type MyType = string | number; let x: MyType = 'hello';

Type not in union.

TypeScript

class Product {{ int a; }} obj.a=5;

class Product {{ public int a; }} obj.a=5;

Make field public.

Java

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

Use CSS.

HTML

let a = 'output'

let a = "output"

Double quotes.

Swift

data[28]

if (length(data) >= 28) data[28]

Check length.

R

match count {{ 1 => {{}} }}

match count {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

[29, 48, 27

[29, 48, 27]

Close bracket.

Ruby

h1 {{ font-size:70px color:green; }}

h1 {{ font-size:70px; color:green; }}

Add semicolon.

CSS

val val: Int = 'test'

val val: String = 'test'

Fix type.

Kotlin

if (index = 45) {{}}

if (index === 45) {{}}

Use === for equality.

JavaScript

val temp = 49; temp = 91

var temp = 49; temp = 91

Use var for reassignment.

Scala

name: info value: hello,

name: info value: hello

Remove comma.

YAML

class Person def method end end

Correct.

Ruby

values[10]

if (values.indices.contains(10)) values[10]

Check index.

Kotlin

int arr[21]; arr[21]=5;

int arr[21]; if(21<21){{}} else arr[21]=5;

Bounds check.

C++