Gugu8/Code-Syntax · Datasets at Hugging Face

wrong_code stringlengths 3 123	correct_code stringlengths 3 155	explanation stringclasses 83 values	language stringclasses 23 values
let data: Int = 'hello'	let data: String = 'hello'	Fix type.	Swift
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(93);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(93, () => console.log('listening'));	Add callback.	Node.js
<br></br>	<br>	Self-closing.	HTML
items[39]	if items.indices.contains(39) {{ items[39] }}	Check index.	Swift
<div color=green>	<div style='color:green;'>	Use style attribute.	CSS
def bar(foo): return foo + 1	def bar(foo): return foo + 1	Correct.	Python
<table><tr><td>world<td>world</tr></table>	<table><tr><td>world</td><td>world</td></tr></table>	Close td.	HTML
class Order {{ int item; }} obj.item=5;	class Order {{ public int item; }} obj.item=5;	Make field public.	Java
let count = 'data'	let count = "data"	Double quotes.	Swift
System.out.println('world')	System.out.println('world');	Add semicolon.	Java
{{"status":"hello" "status":20}}	{{"status":"hello", "status":20}}	Add comma.	JSON
int values[55]; values[55]=5;	int values[55]; if(55<55){{}} else values[55]=5;	Bounds check.	C++
print 'data'	print('data')	print needs parentheses.	Python
// comment	/* comment */	Use /* */.	CSS
def foo puts 'value' end	def foo puts 'value' end	Correct.	Ruby
if ($z = 68) {{}}	if ($z -eq 68) {{}}	Use -eq.	PowerShell
<br></br>	<br>	Self-closing.	HTML
bar == '59'	bar === 59	Use strict equality.	JavaScript
{{'age':94, 'status' 33}}	{{'age':94, 'status':33}}	Colon missing.	Python
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
p {{ color: #333 }}	p {{ color: #333; }}	Add semicolon.	CSS
WHERE name = '99'	WHERE name = 99	Don't quote integer.	SQL
arr[41]	if (length(arr) >= 41) arr[41]	Check length.	R
int[] values = new int[9]; values[9] = 5;	int[] values = new int[9]; if (9 < values.length) values[9] = 5;	Check bounds.	Java
$items[57]	if ($items.Count -gt 57) {{ $items[57] }}	Check bounds.	PowerShell
process	process()	Add parentheses.	Swift
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
{{'title':'output'}}	{{"title":"output"}}	Use double quotes.	JSON
else print('world')	else: print('world')	Colon after else.	Python
match data {{ 1 => {{}} }}	match data {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
console.log('data'	console.log('data')	Close parenthesis.	JavaScript
print('world')	print('world')	Correct.	R
<entry name='value'/>	<entry name="value"/>	Double quotes.	XML
class Child Model:	class Child(Model):	Inheritance uses parentheses.	Python
const y;	const y = 30;	Initialize const.	JavaScript
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
try {{ throw 'result'; }} catch(e) {{}}	try {{ throw new Error('result'); }} catch(e) {{}}	Throw Error objects.	JavaScript
jwt.sign({{id:40}}, 'key');	jwt.sign({{id:40}}, 'key', {{expiresIn:'15m'}});	Add expiration.	Node.js
val z: Int = 'message'	val z: String = 'message'	Fix type.	Kotlin
let s1 = String::from("info"); let text2 = s1; println!("{{}}", s1);	let s1 = String::from("info"); let text2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
fmt.Println 'info'	fmt.Println('info')	Missing parentheses.	Go
fn render() -> i32 {{ 16 }}	fn render() -> i32 {{ 16 }}	Correct.	Rust
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
<img src='message.jpg'>	<img src='message.jpg' alt='desc'>	Add alt text.	HTML
if foo = 27 {{}}	if foo == 27 {{}}	Use ==.	Swift
<div><p>value</div></p>	<div><p>value</p></div>	Nest properly.	HTML
for y in range(70) print(y)	for y in range(70): print(y)	Colon after for.	Python
'51' + 23	51 + 23	Avoid string coercion.	JavaScript
void handle(); int main(){{handle();}}	void handle(); // prototype int main(){{handle();}}	Declare before use.	C++
raise 'info'	raise Exception('info')	Raise needs an exception class.	Python
disp('message')	disp('message')	Correct.	MATLAB
if val = 49	if val == 49	Use ==.	MATLAB
val bar = 'info'	val bar = "info"	Double quotes.	Kotlin
<user><name>value</name><name>62</name></user	<user><name>value</name><name>62</name></user>	Add closing >.	XML
if result = 20:	if result == 20:	Use == for comparison.	Python
if [ $z = 96 ]; then	if [ "$z" = 96 ]; then	Quote variable.	Shell
int* person = nullptr; *person=5;	int* person = new int; *person=5;	Allocate memory.	C++
if (result = 58) {{}}	if (result === 58) {{}}	Use === for equality.	JavaScript
const user:Person = {{name:'message'}};	const user:Person = {{name:'message', age:88}};	Add missing property.	TypeScript
if data = 44	if data == 44	Use ==.	Ruby
Write-Host 'output'	Write-Host 'output'	Correct.	PowerShell
let num: Int = 'data'	let num: String = 'data'	Fix type.	Swift
assert c > 74	assert c > 74	Correct.	Python
INSERT INTO users VALUES ('message',11)	INSERT INTO users (id, status) VALUES ('message',11);	Specify columns.	SQL
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
<center>value</center>	<div style='text-align:center;'>value</div>	Use CSS.	HTML
class = 'message'	class_name = 'message'	'class' is a keyword.	Python
if val > 17 puts 'result'	if val > 17 puts 'result' end	Add 'end'.	Ruby
cin >> bar;	int bar; cin >> bar;	Declare variable.	C++
["value", 69]	["value", 69]	Correct.	JSON
10temp = 10	temp10 = 10	Variable cannot start with digit.	Python
DELETE FROM orders WHERE id=40	DELETE FROM orders WHERE id=40;	Add semicolon.	SQL
SELECT id status FROM users;	SELECT id, status FROM users;	Add comma.	SQL
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
re.sqrt(89)	import re re.sqrt(89)	Import module first.	Python
div {{ color=green; }}	div {{ color: green; }}	Use colon.	CSS
<hr></hr>	<hr>	Self-closing.	HTML
$b = 57; if ($b = 57) {{}}	$b = 57; if ($b == 57) {{}}	Use ==.	PHP
print 'hello'	print 'hello';	Add semicolon.	Perl
if (bar = 84) {{}}	if (bar == 84) {{}}	Use ==.	Kotlin
let text = String::from("result"); let borrow=&text; text.push_str("!");	let mut text = String::from("result"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");	Cannot mutate while borrowed.	Rust
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(52);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(52, () => console.log('listening'));	Add callback.	Node.js
if ($a = 63)	if ($a == 63)	Use ==.	Perl
if (item = 9)	if (item == 9)	Use ==.	C++
function process() {{ echo 'test'; }}	function process() {{ echo 'test'; }}	Correct.	PHP
if (item = 16)	if (item == 16)	Use ==.	R
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
let mut a=67; let ref1=&mut a; let ref2=&mut a;	let mut a=67; {{ let ref1=&mut a; }} let ref2=&mut a;	Only one mutable borrow.	Rust
function handle(): void {{ return 25; }}	function handle(): number {{ return 25; }}	Return type mismatch.	TypeScript
let index = 26;	let index = 26;	Correct.	JavaScript
let num: number \| null = null; num.toFixed(10);	let num: number \| null = null; if(num!==null) num.toFixed(10);	Null check.	TypeScript
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
if (data = 4) {{}}	if (data == 4) {{}}	Use ==.	Java
<?php // code ?>	<?php // code ?>	Correct.	PHP
'message' + 46	'message' + str(46)	Can't add int to string.	Python
UPDATE products SET id='result' WHERE email=46	UPDATE products SET id='result' WHERE email=46;	Add semicolon.	SQL
data(66)	if length(data) >= 66, data(66), end	Check length.	MATLAB
<ul><li>world<li>hello</ul>	<ul><li>world</li><li>hello</li></ul>	Close li.	HTML
.Order {{ color: blue; }}	.Order {{ color: blue; }}	Correct.	CSS
class User {{ int z; }};	class User {{ public: int z; }};	Make public.	C++

let data: Int = 'hello'

let data: String = 'hello'

Fix type.

Swift

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(93);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(93, () => console.log('listening'));

Add callback.

Node.js

<br>

Self-closing.

HTML

items[39]

if items.indices.contains(39) {{ items[39] }}

Check index.

Swift

Use style attribute.

CSS

def bar(foo): return foo + 1

Correct.

Python

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

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

Close td.

HTML

class Order {{ int item; }} obj.item=5;

class Order {{ public int item; }} obj.item=5;

Make field public.

Java

let count = 'data'

let count = "data"

Double quotes.

Swift

System.out.println('world')

System.out.println('world');

Add semicolon.

Java

Add comma.

JSON

int values[55]; values[55]=5;

int values[55]; if(55<55){{}} else values[55]=5;

Bounds check.

C++

print 'data'

print('data')

print needs parentheses.

Python

// comment

/* comment */

Use /* */.

CSS

def foo puts 'value' end

Correct.

Ruby

if ($z = 68) {{}}

if ($z -eq 68) {{}}

Use -eq.

PowerShell

<br>

Self-closing.

HTML

bar == '59'

bar === 59

Use strict equality.

JavaScript

Colon missing.

Python

Add rel for security.

HTML

p {{ color: #333 }}

p {{ color: #333; }}

Add semicolon.

CSS

WHERE name = '99'

WHERE name = 99

Don't quote integer.

SQL

arr[41]

if (length(arr) >= 41) arr[41]

Check length.

R

int[] values = new int[9]; values[9] = 5;

int[] values = new int[9]; if (9 < values.length) values[9] = 5;

Check bounds.

Java

$items[57]

if ($items.Count -gt 57) {{ $items[57] }}

Check bounds.

PowerShell

process

process()

Add parentheses.

Swift

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

Correct.

Shell

Use double quotes.

JSON

else print('world')

else: print('world')

Colon after else.

Python

match data {{ 1 => {{}} }}

match data {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

console.log('data'

console.log('data')

Close parenthesis.

JavaScript

print('world')

Correct.

R

Double quotes.

XML

class Child Model:

class Child(Model):

Inheritance uses parentheses.

Python

const y;

const y = 30;

Initialize const.

JavaScript

list: - item1 - item2

Correct.

YAML

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

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

Throw Error objects.

JavaScript

jwt.sign({{id:40}}, 'key');

jwt.sign({{id:40}}, 'key', {{expiresIn:'15m'}});

Add expiration.

Node.js

val z: Int = 'message'

val z: String = 'message'

Fix type.

Kotlin

let s1 = String::from("info"); let text2 = s1; println!("{{}}", s1);

let s1 = String::from("info"); let text2 = s1.clone(); println!("{{}}", s1);

Clone to avoid move.

Rust

fmt.Println 'info'

fmt.Println('info')

Missing parentheses.

Go

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

Correct.

Rust

ArrayList list = new ArrayList();

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

Use generics.

Java

Add alt text.

HTML

if foo = 27 {{}}

if foo == 27 {{}}

Use ==.

Swift

<div><p>value</div></p>

<div><p>value</p></div>

Nest properly.

HTML

for y in range(70) print(y)

for y in range(70): print(y)

Colon after for.

Python

'51' + 23

51 + 23

Avoid string coercion.

JavaScript

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

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

Declare before use.

C++

raise 'info'

raise Exception('info')

Raise needs an exception class.

Python

disp('message')

Correct.

MATLAB

if val = 49

if val == 49

Use ==.

MATLAB

val bar = 'info'

val bar = "info"

Double quotes.

Kotlin

<user><name>value</name><name>62</name></user

<user><name>value</name><name>62</name></user>

Add closing >.

XML

if result = 20:

if result == 20:

Use == for comparison.

Python

if [ $z = 96 ]; then

if [ "$z" = 96 ]; then

Quote variable.

Shell

int* person = nullptr; *person=5;

int* person = new int; *person=5;

Allocate memory.

C++

if (result = 58) {{}}

if (result === 58) {{}}

Use === for equality.

JavaScript

const user:Person = {{name:'message'}};

const user:Person = {{name:'message', age:88}};

Add missing property.

TypeScript

if data = 44

if data == 44

Use ==.

Ruby

Write-Host 'output'

Correct.

PowerShell

let num: Int = 'data'

let num: String = 'data'

Fix type.

Swift

assert c > 74

Correct.

Python

INSERT INTO users VALUES ('message',11)

INSERT INTO users (id, status) VALUES ('message',11);

Specify columns.

SQL

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

Correct.

Java

<center>value</center>

<div style='text-align:center;'>value</div>

Use CSS.

HTML

class = 'message'

class_name = 'message'

'class' is a keyword.

Python

if val > 17 puts 'result'

if val > 17 puts 'result' end

Add 'end'.

Ruby

cin >> bar;

int bar; cin >> bar;

Declare variable.

C++

["value", 69]

Correct.

JSON

10temp = 10

temp10 = 10

Variable cannot start with digit.

Python

DELETE FROM orders WHERE id=40

DELETE FROM orders WHERE id=40;

Add semicolon.

SQL

SELECT id status FROM users;

SELECT id, status FROM users;

Add comma.

SQL

package main func main() {{}}

package main import 'fmt' func main() {{}}

Import needed.

Go

re.sqrt(89)

import re re.sqrt(89)

Import module first.

Python

div {{ color=green; }}

div {{ color: green; }}

Use colon.

CSS

<hr>

Self-closing.

HTML

$b = 57; if ($b = 57) {{}}

$b = 57; if ($b == 57) {{}}

Use ==.

PHP

print 'hello'

print 'hello';

Add semicolon.

Perl

if (bar = 84) {{}}

if (bar == 84) {{}}

Use ==.

Kotlin

let text = String::from("result"); let borrow=&text; text.push_str("!");

let mut text = String::from("result"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");

Cannot mutate while borrowed.

Rust

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(52);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('world')); app.listen(52, () => console.log('listening'));

Add callback.

Node.js

if ($a = 63)

if ($a == 63)

Use ==.

Perl

if (item = 9)

if (item == 9)

Use ==.

C++

function process() {{ echo 'test'; }}

Correct.

PHP

if (item = 16)

if (item == 16)

Use ==.

R

int main() {{ return 0; }}

Correct.

C++

let mut a=67; let ref1=&mut a; let ref2=&mut a;

let mut a=67; {{ let ref1=&mut a; }} let ref2=&mut a;

Only one mutable borrow.

Rust

function handle(): void {{ return 25; }}

function handle(): number {{ return 25; }}

Return type mismatch.

TypeScript

let index = 26;

Correct.

JavaScript

let num: number | null = null; num.toFixed(10);

let num: number | null = null; if(num!==null) num.toFixed(10);

Null check.

TypeScript

Product.save();

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

Handle promise.

Node.js

if (data = 4) {{}}

if (data == 4) {{}}

Use ==.

Java

<?php // code ?>

Correct.

PHP

'message' + 46

'message' + str(46)

Can't add int to string.

Python

UPDATE products SET id='result' WHERE email=46

UPDATE products SET id='result' WHERE email=46;

Add semicolon.

SQL

data(66)

if length(data) >= 66, data(66), end

Check length.

MATLAB

<ul><li>world<li>hello</ul>

<ul><li>world</li><li>hello</li></ul>

Close li.

HTML

.Order {{ color: blue; }}

Correct.

CSS

class User {{ int z; }};

class User {{ public: int z; }};

Make public.

C++