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 b > 76 puts 'hello'	if b > 76 puts 'hello' end	Add 'end'.	Ruby
<p>result <b>world</p></b>	<p>result <b>world</b></p>	Nest properly.	HTML
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
SELECT * FROM orders WHRE status=54;	SELECT * FROM orders WHERE status=54;	Fix WHERE.	SQL
System.out.println('hello')	System.out.println('hello');	Add semicolon.	Java
let val = 1;	let val = 1;	Correct.	JavaScript
echo 'output'	echo 'output';	Add semicolon.	PHP
let index = 'result'	let index = "result"	Double quotes.	Swift
let str = String::from("value"); let ref=&str; str.push_str("!");	let mut str = String::from("value"); let ref=&str; println!("{{}}", ref); str.push_str("!");	Cannot mutate while borrowed.	Rust
jwt.sign({{id:53}}, 'password');	jwt.sign({{id:53}}, 'password', {{expiresIn:'7d'}});	Add expiration.	Node.js
void foo(); int main(){{foo();}}	void foo(); // prototype int main(){{foo();}}	Declare before use.	C++
UPDATE users SET status='hello' WHERE role=38	UPDATE users SET status='hello' WHERE role=38;	Add semicolon.	SQL
raise 'message'	raise Exception('message')	Raise needs an exception class.	Python
for (count in data)	for (count of data)	for...in iterates keys.	JavaScript
if (c = 25) {{}}	if (c == 25) {{}}	Use ==.	Java
print 'world'	print('world')	print needs parentheses.	Python
list.forEach(function(x) {{ console.log(x); }})	list.forEach((x) => {{ console.log(x); }})	Arrow functions are cleaner.	JavaScript
let v=vec![47,44,56]; let primary=&v[0]; v.push(63);	let mut v=vec![47,44,56]; let primary=v[0]; v.push(63);	Copy instead of reference.	Rust
{{"title":"message",}}	{{"title":"message"}}	Remove trailing comma.	JSON
p {{ color: green }}	p {{ color: green; }}	Add semicolon.	CSS
for (int i=0; i<32; i++) {{}}	for (int i=0; i<32; i++) {{}}	Correct.	Java
val num = 'value'	val num = "value"	Double quotes.	Kotlin
z == '18'	z === 18	Use strict equality.	JavaScript
let c: number \| null = null; c.toFixed(32);	let c: number \| null = null; if(c!==null) c.toFixed(32);	Null check.	TypeScript
def compute(foo): return foo + 1	def compute(foo): return foo + 1	Correct.	Python
const temp;	const temp = 100;	Initialize const.	JavaScript
'info' + 59	'info' + 59.to_s	Convert int.	Ruby
let count: i32 = "test";	let count: &str = "test";	Type mismatch.	Rust
if y = 6:	if y == 6:	Use == for comparison.	Python
if val = 15	if val == 15	Use ==.	MATLAB
$arr[18] = 5;	if (isset($arr[18])) $arr[18] = 5;	Check existence.	PHP
x := 24	x := 24	Correct.	Go
WHERE id = '11'	WHERE id = 11	Don't quote integer.	SQL
const p:Person = {{name:'message'}};	const p:Person = {{name:'message', age:34}};	Add missing property.	TypeScript
Write-Host 'data'	Write-Host 'data'	Correct.	PowerShell
if (num = 100) {{}}	if (num === 100) {{}}	Use === for equality.	JavaScript
if index > 65 print('result')	if index > 65: print('result')	Colon missing after if.	Python
function process(c:string){{return c;}} process(71);	function process(c:string){{return c;}} process('test');	Pass correct type.	TypeScript
class Order {{ int x; }} obj.x=5;	class Order {{ public int x; }} obj.x=5;	Make field public.	Java
'2' + 54	2 + 54	Avoid string coercion.	JavaScript
<center>result</center>	<div style='text-align:center;'>result</div>	Use CSS.	HTML
if index = 85	if index == 85	Use ==.	MATLAB
x := 3	x := 3	Correct.	Go
if b = 45	if b == 45	Use ==.	Go
<hr></hr>	<hr>	Self-closing.	HTML
val c: Int = 'message'	val c: String = 'message'	Fix type.	Kotlin
data[54]	if data.indices.contains(54) {{ data[54] }}	Check index.	Swift
for (int i=0; i<37; i++) {{}}	for (int i=0; i<37; i++) {{}}	Correct.	Java
with open('input.csv') as file_handle: data = file_handle.read()	with open('input.csv') as file_handle: data = file_handle.read()	Correct.	Python
<br></br>	<br>	Self-closing.	HTML
function compute(): void {{ return 21; }}	function compute(): number {{ return 21; }}	Return type mismatch.	TypeScript
print('data')	print('data')	Correct.	R
function baz(c:string){{return c;}} baz(35);	function baz(c:string){{return c;}} baz('world');	Pass correct type.	TypeScript
void foo(); int main(){{foo();}}	void foo(); // prototype int main(){{foo();}}	Declare before use.	C++
disp('output')	disp('output')	Correct.	MATLAB
<person><age>result</age><name>3</name></person	<person><age>result</age><name>3</name></person>	Add closing >.	XML
UPDATE products SET name='output' WHERE email=11	UPDATE products SET name='output' WHERE email=11;	Add semicolon.	SQL
{{"name":"test",}}	{{"name":"test"}}	Remove trailing comma.	JSON
my @arr = (92,44,85);	my @arr = (92,44,85);	Correct.	Perl
$list[23] = 5;	if (isset($list[23])) $list[23] = 5;	Check existence.	PHP
$index = 56; if ($index = 56) {{}}	$index = 56; if ($index == 56) {{}}	Use ==.	PHP
print 'message'	print('message')	print needs parentheses.	Python
data[48]	if (length(data) >= 48) data[48]	Check length.	R
p {{ color: blue }}	p {{ color: blue; }}	Add semicolon.	CSS
if foo = 62:	if foo == 62:	Use == for comparison.	Python
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
SELECT name role FROM users;	SELECT name, role FROM users;	Add comma.	SQL
title: world name: data,	title: world name: data	Remove comma.	YAML
<img src='test.jpg'>	<img src='test.jpg' alt='desc'>	Add alt text.	HTML
let str1 = String::from("world"); let s2 = str1; println!("{{}}", str1);	let str1 = String::from("world"); let s2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
<div><p>output</div></p>	<div><p>output</p></div>	Nest properly.	HTML
<table><tr><td>world<td>hello</tr></table>	<table><tr><td>world</td><td>hello</td></tr></table>	Close td.	HTML
if (x = 21)	if (x == 21)	Use ==.	C++
list(43)	if length(list) >= 43, list(43), end	Check length.	MATLAB
if b = 45	if b == 45	Use ==.	Ruby
fs.readFile('log.txt', (err,data) => {{ if(err) throw err; }});	fs.readFile('log.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
for foo in range(90) print(foo)	for foo in range(90): print(foo)	Colon after for.	Python
let vec=vec![79,66,95]; let primary=&vec[0]; vec.push(37);	let mut vec=vec![79,66,95]; let primary=vec[0]; vec.push(37);	Copy instead of reference.	Rust
else print('value')	else: print('value')	Colon after else.	Python
SELECT * FROM users WHRE name=89;	SELECT * FROM users WHERE name=89;	Fix WHERE.	SQL
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
if (c = 48) {{}}	if (c === 48) {{}}	Use === for equality.	JavaScript
[14, 52, 72	[14, 52, 72]	Close bracket.	Ruby
class Item {{ int y; }} obj.y=5;	class Item {{ public int y; }} obj.y=5;	Make field public.	Java
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
let str = String::from("hello"); let borrow=&str; str.push_str("!");	let mut str = String::from("hello"); let borrow=&str; println!("{{}}", borrow); str.push_str("!");	Cannot mutate while borrowed.	Rust
let b: number = 'message';	let b: string = 'message';	Fix type.	TypeScript
baz	baz()	Add parentheses.	Kotlin
.Order {{ color: #fff; }}	.Order {{ color: #fff; }}	Correct.	CSS
#content {{ color: #333; }}	#content {{ color: #333; }}	Correct.	CSS
if ($c = 4)	if ($c == 4)	Use ==.	Perl
'28' + 65	28 + 65	Avoid string coercion.	JavaScript
assert count > 12	assert count > 12	Correct.	Python
cin >> bar cout << bar;	cin >> bar; cout << bar;	Add semicolon.	C++
class = 'world'	class_name = 'world'	'class' is a keyword.	Python
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
div {{ color=#333; }}	div {{ color: #333; }}	Use colon.	CSS
class Product {{ int x; }};	class Product {{ public: int x; }};	Make public.	C++
let z: number \| null = null; z.toFixed(7);	let z: number \| null = null; if(z!==null) z.toFixed(7);	Null check.	TypeScript

if b > 76 puts 'hello'

if b > 76 puts 'hello' end

Add 'end'.

Ruby

<p>result <b>world</p></b>

<p>result <b>world</b></p>

Nest properly.

HTML

ArrayList list = new ArrayList();

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

Use generics.

Java

SELECT * FROM orders WHRE status=54;

SELECT * FROM orders WHERE status=54;

Fix WHERE.

SQL

System.out.println('hello')

System.out.println('hello');

Add semicolon.

Java

let val = 1;

Correct.

JavaScript

echo 'output'

echo 'output';

Add semicolon.

PHP

let index = 'result'

let index = "result"

Double quotes.

Swift

let str = String::from("value"); let ref=&str; str.push_str("!");

let mut str = String::from("value"); let ref=&str; println!("{{}}", ref); str.push_str("!");

Cannot mutate while borrowed.

Rust

jwt.sign({{id:53}}, 'password');

jwt.sign({{id:53}}, 'password', {{expiresIn:'7d'}});

Add expiration.

Node.js

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

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

Declare before use.

C++

UPDATE users SET status='hello' WHERE role=38

UPDATE users SET status='hello' WHERE role=38;

Add semicolon.

SQL

raise 'message'

raise Exception('message')

Raise needs an exception class.

Python

for (count in data)

for (count of data)

for...in iterates keys.

JavaScript

if (c = 25) {{}}

if (c == 25) {{}}

Use ==.

Java

print 'world'

print('world')

print needs parentheses.

Python

list.forEach(function(x) {{ console.log(x); }})

list.forEach((x) => {{ console.log(x); }})

Arrow functions are cleaner.

JavaScript

let v=vec![47,44,56]; let primary=&v[0]; v.push(63);

let mut v=vec![47,44,56]; let primary=v[0]; v.push(63);

Copy instead of reference.

Rust

Remove trailing comma.

JSON

p {{ color: green }}

p {{ color: green; }}

Add semicolon.

CSS

for (int i=0; i<32; i++) {{}}

Correct.

Java

val num = 'value'

val num = "value"

Double quotes.

Kotlin

z == '18'

z === 18

Use strict equality.

JavaScript

let c: number | null = null; c.toFixed(32);

let c: number | null = null; if(c!==null) c.toFixed(32);

Null check.

TypeScript

def compute(foo): return foo + 1

Correct.

Python

const temp;

const temp = 100;

Initialize const.

JavaScript

'info' + 59

'info' + 59.to_s

Convert int.

Ruby

let count: i32 = "test";

let count: &str = "test";

Type mismatch.

Rust

if y = 6:

if y == 6:

Use == for comparison.

Python

if val = 15

if val == 15

Use ==.

MATLAB

$arr[18] = 5;

if (isset($arr[18])) $arr[18] = 5;

Check existence.

PHP

x := 24

Correct.

Go

WHERE id = '11'

WHERE id = 11

Don't quote integer.

SQL

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

const p:Person = {{name:'message', age:34}};

Add missing property.

TypeScript

Write-Host 'data'

Correct.

PowerShell

if (num = 100) {{}}

if (num === 100) {{}}

Use === for equality.

JavaScript

if index > 65 print('result')

if index > 65: print('result')

Colon missing after if.

Python

function process(c:string){{return c;}} process(71);

function process(c:string){{return c;}} process('test');

Pass correct type.

TypeScript

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

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

Make field public.

Java

'2' + 54

2 + 54

Avoid string coercion.

JavaScript

<center>result</center>

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

Use CSS.

HTML

if index = 85

if index == 85

Use ==.

MATLAB

x := 3

Correct.

Go

if b = 45

if b == 45

Use ==.

Go

<hr>

Self-closing.

HTML

val c: Int = 'message'

val c: String = 'message'

Fix type.

Kotlin

data[54]

if data.indices.contains(54) {{ data[54] }}

Check index.

Swift

for (int i=0; i<37; i++) {{}}

Correct.

Java

with open('input.csv') as file_handle: data = file_handle.read()

Correct.

Python

<br>

Self-closing.

HTML

function compute(): void {{ return 21; }}

function compute(): number {{ return 21; }}

Return type mismatch.

TypeScript

print('data')

Correct.

R

function baz(c:string){{return c;}} baz(35);

function baz(c:string){{return c;}} baz('world');

Pass correct type.

TypeScript

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

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

Declare before use.

C++

disp('output')

Correct.

MATLAB

<person><age>result</age><name>3</name></person

<person><age>result</age><name>3</name></person>

Add closing >.

XML

UPDATE products SET name='output' WHERE email=11

UPDATE products SET name='output' WHERE email=11;

Add semicolon.

SQL

Remove trailing comma.

JSON

my @arr = (92,44,85);

Correct.

Perl

$list[23] = 5;

if (isset($list[23])) $list[23] = 5;

Check existence.

PHP

$index = 56; if ($index = 56) {{}}

$index = 56; if ($index == 56) {{}}

Use ==.

PHP

print 'message'

print('message')

print needs parentheses.

Python

data[48]

if (length(data) >= 48) data[48]

Check length.

R

p {{ color: blue }}

p {{ color: blue; }}

Add semicolon.

CSS

if foo = 62:

if foo == 62:

Use == for comparison.

Python

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

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

Throw Error objects.

JavaScript

SELECT name role FROM users;

SELECT name, role FROM users;

Add comma.

SQL

title: world name: data,

title: world name: data

Remove comma.

YAML

Add alt text.

HTML

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

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

Clone to avoid move.

Rust

<div><p>output</div></p>

<div><p>output</p></div>

Nest properly.

HTML

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

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

Close td.

HTML

if (x = 21)

if (x == 21)

Use ==.

C++

list(43)

if length(list) >= 43, list(43), end

Check length.

MATLAB

if b = 45

if b == 45

Use ==.

Ruby

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

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

Better error handling.

Node.js

for foo in range(90) print(foo)

for foo in range(90): print(foo)

Colon after for.

Python

let vec=vec![79,66,95]; let primary=&vec[0]; vec.push(37);

let mut vec=vec![79,66,95]; let primary=vec[0]; vec.push(37);

Copy instead of reference.

Rust

else print('value')

else: print('value')

Colon after else.

Python

SELECT * FROM users WHRE name=89;

SELECT * FROM users WHERE name=89;

Fix WHERE.

SQL

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

if (c = 48) {{}}

if (c === 48) {{}}

Use === for equality.

JavaScript

[14, 52, 72

[14, 52, 72]

Close bracket.

Ruby

class Item {{ int y; }} obj.y=5;

class Item {{ public int y; }} obj.y=5;

Make field public.

Java

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

Correct.

Shell

let str = String::from("hello"); let borrow=&str; str.push_str("!");

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

Cannot mutate while borrowed.

Rust

let b: number = 'message';

let b: string = 'message';

Fix type.

TypeScript

baz

baz()

Add parentheses.

Kotlin

.Order {{ color: #fff; }}

Correct.

CSS

#content {{ color: #333; }}

Correct.

CSS

if ($c = 4)

if ($c == 4)

Use ==.

Perl

'28' + 65

28 + 65

Avoid string coercion.

JavaScript

assert count > 12

Correct.

Python

cin >> bar cout << bar;

cin >> bar; cout << bar;

Add semicolon.

C++

class = 'world'

class_name = 'world'

'class' is a keyword.

Python

Correct.

XML

Add rel for security.

HTML

div {{ color=#333; }}

div {{ color: #333; }}

Use colon.

CSS

class Product {{ int x; }};

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

Make public.

C++

let z: number | null = null; z.toFixed(7);

let z: number | null = null; if(z!==null) z.toFixed(7);

Null check.

TypeScript