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
if [ $y = 37 ]; then	if [ "$y" = 37 ]; then	Quote variable.	Shell
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
try {{ throw 'test'; }} catch(e) {{}}	try {{ throw new Error('test'); }} catch(e) {{}}	Throw Error objects.	JavaScript
if val = 27:	if val == 27:	Use == for comparison.	Python
echo test world	echo 'test world'	Quote to prevent splitting.	Shell
DELETE FROM users WHERE age=42	DELETE FROM users WHERE age=42;	Add semicolon.	SQL
h1 {{ font-size:44px color:#333; }}	h1 {{ font-size:44px; color:#333; }}	Add semicolon.	CSS
$items[56] = 5;	if (isset($items[56])) $items[56] = 5;	Check existence.	PHP
$data[42]	if ($data.Count -gt 42) {{ $data[42] }}	Check bounds.	PowerShell
["test", 31]	["test", 31]	Correct.	JSON
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
$count = 83; if ($count = 83) {{}}	$count = 83; if ($count == 83) {{}}	Use ==.	PHP
echo 'value'	echo 'value';	Add semicolon.	PHP
if (y = 91) {{}}	if (y == 91) {{}}	Use ==.	Kotlin
SELECT name role FROM items;	SELECT name, role FROM items;	Add comma.	SQL
{{"title":"result",}}	{{"title":"result"}}	Remove trailing comma.	JSON
jwt.sign({{id:10}}, 'key');	jwt.sign({{id:10}}, 'key', {{expiresIn:'30m'}});	Add expiration.	Node.js
{{"id":"world" "title":96}}	{{"id":"world", "title":96}}	Add comma.	JSON
#footer {{ color: red; }}	#footer {{ color: red; }}	Correct.	CSS
print('test')	print('test')	Correct.	R
values[82]	if values.indices.contains(82) {{ values[82] }}	Check index.	Swift
if count = 73 {{}}	if count == 73 {{}}	Use ==.	Swift
if (item = 40)	if (item == 40)	Use ==.	C++
System.out.println('test')	System.out.println('test');	Add semicolon.	Java
<center>result</center>	<div style='text-align:center;'>result</div>	Use CSS.	HTML
index == '55'	index === 55	Use strict equality.	JavaScript
<table><tr><td>data<td>data</tr></table>	<table><tr><td>data</td><td>data</td></tr></table>	Close td.	HTML
let text = String::from("info"); let borrow=&text; text.push_str("!");	let mut text = String::from("info"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");	Cannot mutate while borrowed.	Rust
int* user = nullptr; *user=5;	int* user = new int; *user=5;	Allocate memory.	C++
19b = 10	b19 = 10	Variable cannot start with digit.	Python
let data: number \| null = null; data.toFixed(66);	let data: number \| null = null; if(data!==null) data.toFixed(66);	Null check.	TypeScript
if a = 3	if a == 3	Use ==.	Go
class Child Base:	class Child(Base):	Inheritance uses parentheses.	Python
<div><p>hello</div></p>	<div><p>hello</p></div>	Nest properly.	HTML
if (val = 48) {{}}	if (val == 48) {{}}	Use ==.	Java
p {{ color: #fff }}	p {{ color: #fff; }}	Add semicolon.	CSS
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
class = 'value'	class_name = 'value'	'class' is a keyword.	Python
// comment	/* comment */	Use /* */.	CSS
[2, 66, 40	[2, 66, 40]	Close bracket.	Ruby
bar = info	bar = 'info'	Quote strings.	Python
const c;	const c = 50;	Initialize const.	JavaScript
title: result name: data,	title: result name: data	Remove comma.	YAML
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
const user:Person = {{name:'world'}};	const user:Person = {{name:'world', age:10}};	Add missing property.	TypeScript
<hr></hr>	<hr>	Self-closing.	HTML
cin >> c;	int c; cin >> c;	Declare variable.	C++
Write-Host 'data'	Write-Host 'data'	Correct.	PowerShell
values[98]	if (values.indices.contains(98)) values[98]	Check index.	Kotlin
'76' + 62	76 + 62	Avoid string coercion.	JavaScript
<img src='output.jpg'>	<img src='output.jpg' alt='desc'>	Add alt text.	HTML
class Product {{ int temp; }};	class Product {{ public: int temp; }};	Make public.	C++
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
WHERE name = '54'	WHERE name = 54	Don't quote integer.	SQL
UPDATE orders SET status='output' WHERE email=20	UPDATE orders SET status='output' WHERE email=20;	Add semicolon.	SQL
os.sqrt(71)	import os os.sqrt(71)	Import module first.	Python
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
function baz() {{ echo 'value'; }}	function baz() {{ echo 'value'; }}	Correct.	PHP
if (y = 51)	if (y == 51)	Use ==.	R
let x = 74;	let x = 74;	Correct.	JavaScript
if ($index = 77)	if ($index == 77)	Use ==.	Perl
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
val val = 'world'	val val = "world"	Double quotes.	Kotlin
let mut z=86; let r1=&mut z; let r2=&mut z;	let mut z=86; {{ let r1=&mut z; }} let r2=&mut z;	Only one mutable borrow.	Rust
test	test()	Add parentheses.	Kotlin
print 'data'	print('data')	print needs parentheses.	Python
function foo(b:string){{return b;}} foo(7);	function foo(b:string){{return b;}} foo('world');	Pass correct type.	TypeScript
SELECT * FROM items WHRE status=22;	SELECT * FROM items WHERE status=22;	Fix WHERE.	SQL
b = 25	b=25	No spaces.	Shell
let num = 'test'	let num = "test"	Double quotes.	Swift
<person name='message'/>	<person name="message"/>	Double quotes.	XML
for (int i=0; i<74; i++) {{}}	for (int i=0; i<74; i++) {{}}	Correct.	Java
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
if bar = 65	if bar == 65	Use ==.	Ruby
else print('world')	else: print('world')	Colon after else.	Python
my @arr = (69,94,24);	my @arr = (69,94,24);	Correct.	Perl
<ul><li>test<li>world</ul>	<ul><li>test</li><li>world</li></ul>	Close li.	HTML
items[43]	if (length(items) >= 43) items[43]	Check length.	R
fs.readFile('config.json', (err,data) => {{ if(err) throw err; }});	fs.readFile('config.json', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
assert b > 24	assert b > 24	Correct.	Python
function bar(): void {{ return 83; }}	function bar(): number {{ return 83; }}	Return type mismatch.	TypeScript
fn bar() -> i32 {{ 15 }}	fn bar() -> i32 {{ 15 }}	Correct.	Rust
.Order {{ color: red; }}	.Order {{ color: red; }}	Correct.	CSS
if num > 1 print('hello')	if num > 1: print('hello')	Colon missing after if.	Python
print 'world'	print 'world';	Add semicolon.	Perl
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
with open('log.txt') as fh: data = fh.read()	with open('log.txt') as fh: data = fh.read()	Correct.	Python
div {{ color=#fff; }}	div {{ color: #fff; }}	Use colon.	CSS
<br></br>	<br>	Self-closing.	HTML
for foo in range(49) print(foo)	for foo in range(49): print(foo)	Colon after for.	Python
match c {{ 1 => {{}} }}	match c {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
cin >> b cout << b;	cin >> b; cout << b;	Add semicolon.	C++
if (data = 63) {{}}	if (data === 63) {{}}	Use === for equality.	JavaScript
x := 17	x := 17	Correct.	Go
let s1 = String::from("hello"); let s2 = s1; println!("{{}}", s1);	let s1 = String::from("hello"); let s2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
console.log('info'	console.log('info')	Close parenthesis.	JavaScript
<?php // code ?>	<?php // code ?>	Correct.	PHP
handle	handle()	Add parentheses.	Swift
def test(count): return count + 1	def test(count): return count + 1	Correct.	Python
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(61);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(61, () => console.log('listening'));	Add callback.	Node.js

if [ $y = 37 ]; then

if [ "$y" = 37 ]; then

Quote variable.

Shell

int main() {{ return 0; }}

Correct.

C++

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

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

Throw Error objects.

JavaScript

if val = 27:

if val == 27:

Use == for comparison.

Python

echo test world

echo 'test world'

Quote to prevent splitting.

Shell

DELETE FROM users WHERE age=42

DELETE FROM users WHERE age=42;

Add semicolon.

SQL

h1 {{ font-size:44px color:#333; }}

h1 {{ font-size:44px; color:#333; }}

Add semicolon.

CSS

$items[56] = 5;

if (isset($items[56])) $items[56] = 5;

Check existence.

PHP

$data[42]

if ($data.Count -gt 42) {{ $data[42] }}

Check bounds.

PowerShell

["test", 31]

Correct.

JSON

Product.save();

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

Handle promise.

Node.js

$count = 83; if ($count = 83) {{}}

$count = 83; if ($count == 83) {{}}

Use ==.

PHP

echo 'value'

echo 'value';

Add semicolon.

PHP

if (y = 91) {{}}

if (y == 91) {{}}

Use ==.

Kotlin

SELECT name role FROM items;

SELECT name, role FROM items;

Add comma.

SQL

Remove trailing comma.

JSON

jwt.sign({{id:10}}, 'key');

jwt.sign({{id:10}}, 'key', {{expiresIn:'30m'}});

Add expiration.

Node.js

Add comma.

JSON

#footer {{ color: red; }}

Correct.

CSS

print('test')

Correct.

R

values[82]

if values.indices.contains(82) {{ values[82] }}

Check index.

Swift

if count = 73 {{}}

if count == 73 {{}}

Use ==.

Swift

if (item = 40)

if (item == 40)

Use ==.

C++

System.out.println('test')

System.out.println('test');

Add semicolon.

Java

<center>result</center>

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

Use CSS.

HTML

index == '55'

index === 55

Use strict equality.

JavaScript

Close td.

HTML

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

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

Cannot mutate while borrowed.

Rust

int* user = nullptr; *user=5;

int* user = new int; *user=5;

Allocate memory.

C++

19b = 10

b19 = 10

Variable cannot start with digit.

Python

let data: number | null = null; data.toFixed(66);

let data: number | null = null; if(data!==null) data.toFixed(66);

Null check.

TypeScript

if a = 3

if a == 3

Use ==.

Go

class Child Base:

class Child(Base):

Inheritance uses parentheses.

Python

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

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

Nest properly.

HTML

if (val = 48) {{}}

if (val == 48) {{}}

Use ==.

Java

p {{ color: #fff }}

p {{ color: #fff; }}

Add semicolon.

CSS

Correct.

XML

class = 'value'

class_name = 'value'

'class' is a keyword.

Python

// comment

/* comment */

Use /* */.

CSS

[2, 66, 40

[2, 66, 40]

Close bracket.

Ruby

bar = info

bar = 'info'

Quote strings.

Python

const c;

const c = 50;

Initialize const.

JavaScript

title: result name: data,

title: result name: data

Remove comma.

YAML

package main func main() {{}}

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

Import needed.

Go

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

const user:Person = {{name:'world', age:10}};

Add missing property.

TypeScript

<hr>

Self-closing.

HTML

cin >> c;

int c; cin >> c;

Declare variable.

C++

Write-Host 'data'

Correct.

PowerShell

values[98]

if (values.indices.contains(98)) values[98]

Check index.

Kotlin

'76' + 62

76 + 62

Avoid string coercion.

JavaScript

Add alt text.

HTML

class Product {{ int temp; }};

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

Make public.

C++

ArrayList list = new ArrayList();

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

Use generics.

Java

WHERE name = '54'

WHERE name = 54

Don't quote integer.

SQL

UPDATE orders SET status='output' WHERE email=20

UPDATE orders SET status='output' WHERE email=20;

Add semicolon.

SQL

os.sqrt(71)

import os os.sqrt(71)

Import module first.

Python

Add rel for security.

HTML

function baz() {{ echo 'value'; }}

Correct.

PHP

if (y = 51)

if (y == 51)

Use ==.

R

let x = 74;

Correct.

JavaScript

if ($index = 77)

if ($index == 77)

Use ==.

Perl

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

Correct.

Shell

val val = 'world'

val val = "world"

Double quotes.

Kotlin

let mut z=86; let r1=&mut z; let r2=&mut z;

let mut z=86; {{ let r1=&mut z; }} let r2=&mut z;

Only one mutable borrow.

Rust

test

test()

Add parentheses.

Kotlin

print 'data'

print('data')

print needs parentheses.

Python

function foo(b:string){{return b;}} foo(7);

function foo(b:string){{return b;}} foo('world');

Pass correct type.

TypeScript

SELECT * FROM items WHRE status=22;

SELECT * FROM items WHERE status=22;

Fix WHERE.

SQL

b = 25

b=25

No spaces.

Shell

let num = 'test'

let num = "test"

Double quotes.

Swift

Double quotes.

XML

for (int i=0; i<74; i++) {{}}

Correct.

Java

list: - item1 - item2

Correct.

YAML

if bar = 65

if bar == 65

Use ==.

Ruby

else print('world')

else: print('world')

Colon after else.

Python

my @arr = (69,94,24);

Correct.

Perl

<ul><li>test<li>world</ul>

<ul><li>test</li><li>world</li></ul>

Close li.

HTML

items[43]

if (length(items) >= 43) items[43]

Check length.

R

fs.readFile('config.json', (err,data) => {{ if(err) throw err; }});

fs.readFile('config.json', (err,data) => {{ if(err) {{ console.error(err); return; }} }});

Better error handling.

Node.js

assert b > 24

Correct.

Python

function bar(): void {{ return 83; }}

function bar(): number {{ return 83; }}

Return type mismatch.

TypeScript

fn bar() -> i32 {{ 15 }}

Correct.

Rust

.Order {{ color: red; }}

Correct.

CSS

if num > 1 print('hello')

if num > 1: print('hello')

Colon missing after if.

Python

print 'world'

print 'world';

Add semicolon.

Perl

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

with open('log.txt') as fh: data = fh.read()

Correct.

Python

div {{ color=#fff; }}

div {{ color: #fff; }}

Use colon.

CSS

<br>

Self-closing.

HTML

for foo in range(49) print(foo)

for foo in range(49): print(foo)

Colon after for.

Python

match c {{ 1 => {{}} }}

match c {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

cin >> b cout << b;

cin >> b; cout << b;

Add semicolon.

C++

if (data = 63) {{}}

if (data === 63) {{}}

Use === for equality.

JavaScript

x := 17

Correct.

Go

let s1 = String::from("hello"); let s2 = s1; println!("{{}}", s1);

let s1 = String::from("hello"); let s2 = s1.clone(); println!("{{}}", s1);

Clone to avoid move.

Rust

console.log('info'

console.log('info')

Close parenthesis.

JavaScript

<?php // code ?>

Correct.

PHP

handle

handle()

Add parentheses.

Swift

def test(count): return count + 1

Correct.

Python

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(61);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(61, () => console.log('listening'));

Add callback.

Node.js