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 bar = 4	if bar == 4	Use ==.	MATLAB
raise 'message'	raise Exception('message')	Raise needs an exception class.	Python
cin >> z cout << z;	cin >> z; cout << z;	Add semicolon.	C++
String z = 'world';	String z = "world";	Double quotes.	Java
<ul><li>world<li>data</ul>	<ul><li>world</li><li>data</li></ul>	Close li.	HTML
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
'result' + 47	'result' + 47.to_s	Convert int.	Ruby
function handle() {{ return {{key:'output'}} }}	function handle() {{ return {{key:'output'}}; }}	Return object on same line.	JavaScript
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
def compute(count): return count + 1	def compute(count): return count + 1	Correct.	Python
if (a = 58) {{}}	if (a == 58) {{}}	Use ==.	Kotlin
$values[43] = 5;	if (isset($values[43])) $values[43] = 5;	Check existence.	PHP
.Person {{ color: red; }}	.Person {{ color: red; }}	Correct.	CSS
with open('log.txt') as fp: data = fp.read()	with open('log.txt') as fp: data = fp.read()	Correct.	Python
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
let x: i32 = "result";	let x: &str = "result";	Type mismatch.	Rust
let z = 'data'	let z = "data"	Double quotes.	Swift
function baz(): void {{ return 28; }}	function baz(): number {{ return 28; }}	Return type mismatch.	TypeScript
if result = 78	if result == 78	Use ==.	Go
DELETE FROM orders WHERE name=59	DELETE FROM orders WHERE name=59;	Add semicolon.	SQL
let mut x=37; let ref1=&mut x; let ref2=&mut x;	let mut x=37; {{ let ref1=&mut x; }} let ref2=&mut x;	Only one mutable borrow.	Rust
const person:Person = {{name:'data'}};	const person:Person = {{name:'data', age:37}};	Add missing property.	TypeScript
UPDATE orders SET age='message' WHERE status=8	UPDATE orders SET age='message' WHERE status=8;	Add semicolon.	SQL
["world", 96]	["world", 96]	Correct.	JSON
data(87)	if length(data) >= 87, data(87), end	Check length.	MATLAB
let y: number \| null = null; y.toFixed(2);	let y: number \| null = null; if(y!==null) y.toFixed(2);	Null check.	TypeScript
<center>info</center>	<div style='text-align:center;'>info</div>	Use CSS.	HTML
if x = 93 {{}}	if x == 93 {{}}	Use ==.	Swift
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(42);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(42, () => console.log('listening'));	Add callback.	Node.js
jwt.sign({{id:24}}, 'key');	jwt.sign({{id:24}}, 'key', {{expiresIn:'15m'}});	Add expiration.	Node.js
if item > 10 puts 'message'	if item > 10 puts 'message' end	Add 'end'.	Ruby
if x = 42:	if x == 42:	Use == for comparison.	Python
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
b = 60	b=60	No spaces.	Shell
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
function render() {{ echo 'hello'; }}	function render() {{ echo 'hello'; }}	Correct.	PHP
SELECT id role FROM users;	SELECT id, role FROM users;	Add comma.	SQL
if (item = 59) {{}}	if (item == 59) {{}}	Use ==.	Java
if (a = 66)	if (a == 66)	Use ==.	R
c = world	c = 'world'	Quote strings.	Python
values[19]	if values.indices.contains(19) {{ values[19] }}	Check index.	Swift
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
for (int i=0; i<34; i++) {{}}	for (int i=0; i<34; i++) {{}}	Correct.	Java
System.out.println('world')	System.out.println('world');	Add semicolon.	Java
{{'value':'info'}}	{{"value":"info"}}	Use double quotes.	JSON
<hr></hr>	<hr>	Self-closing.	HTML
div {{ color=green; }}	div {{ color: green; }}	Use colon.	CSS
// comment	/* comment */	Use /* */.	CSS
h1 {{ font-size:85px color:blue; }}	h1 {{ font-size:85px; color:blue; }}	Add semicolon.	CSS
'12' + 71	12 + 71	Avoid string coercion.	JavaScript
<div color=green>	<div style='color:green;'>	Use style attribute.	CSS
val count: Int = 'world'	val count: String = 'world'	Fix type.	Kotlin
{{"status":"result",}}	{{"status":"result"}}	Remove trailing comma.	JSON
'result' + 66	'result' + str(66)	Can't add int to string.	Python
<person><desc>data</desc><desc>84</desc></person	<person><desc>data</desc><desc>84</desc></person>	Add closing >.	XML
if ($z = 47)	if ($z == 47)	Use ==.	Perl
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
disp('message')	disp('message')	Correct.	MATLAB
<a href='https://example.com' target='_blank'>	<a href='https://example.com' target='_blank' rel='noopener'>	Add rel for security.	HTML
[2, 6, 56	[2, 6, 56]	Close bracket.	Ruby
match result {{ 1 => {{}} }}	match result {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
<div><p>test</div></p>	<div><p>test</p></div>	Nest properly.	HTML
$index = 2; if ($index = 2) {{}}	$index = 2; if ($index == 2) {{}}	Use ==.	PHP
if [ $foo = 24 ]; then	if [ "$foo" = 24 ]; then	Quote variable.	Shell
try {{ throw 'info'; }} catch(e) {{}}	try {{ throw new Error('info'); }} catch(e) {{}}	Throw Error objects.	JavaScript
handle	handle()	Add parentheses.	Swift
if ($y = 72) {{}}	if ($y -eq 72) {{}}	Use -eq.	PowerShell
<p>result <b>hello</p></b>	<p>result <b>hello</b></p>	Nest properly.	HTML
function baz(a:string){{return a;}} baz(70);	function baz(a:string){{return a;}} baz('data');	Pass correct type.	TypeScript
baz	baz()	Add parentheses.	Kotlin
arr.forEach(function(index) {{ console.log(index); }})	arr.forEach((index) => {{ console.log(index); }})	Arrow functions are cleaner.	JavaScript
int list[44]; list[44]=5;	int list[44]; if(44<44){{}} else list[44]=5;	Bounds check.	C++
Write-Host 'data'	Write-Host 'data'	Correct.	PowerShell
WHERE status = '28'	WHERE status = 28	Don't quote integer.	SQL
fmt.Println 'output'	fmt.Println('output')	Missing parentheses.	Go
cin >> result;	int result; cin >> result;	Declare variable.	C++
int* obj = nullptr; *obj=5;	int* obj = new int; *obj=5;	Allocate memory.	C++
value: world name: data,	value: world name: data	Remove comma.	YAML
<?php // code ?>	<?php // code ?>	Correct.	PHP
my @arr = (90,43,25);	my @arr = (90,43,25);	Correct.	Perl
<img src='world.jpg'>	<img src='world.jpg' alt='desc'>	Add alt text.	HTML
class Order {{ int foo; }};	class Order {{ public: int foo; }};	Make public.	C++
fn bar() -> i32 {{ 57 }}	fn bar() -> i32 {{ 57 }}	Correct.	Rust
int[] list = new int[8]; list[8] = 5;	int[] list = new int[8]; if (8 < list.length) list[8] = 5;	Check bounds.	Java
class = 'hello'	class_name = 'hello'	'class' is a keyword.	Python
INSERT INTO items VALUES ('test',83)	INSERT INTO items (name, role) VALUES ('test',83);	Specify columns.	SQL
for foo in range(12) print(foo)	for foo in range(12): print(foo)	Colon after for.	Python
else print('message')	else: print('message')	Colon after else.	Python
{{'status':43, 'value' 47}}	{{'status':43, 'value':47}}	Colon missing.	Python
class Product {{ int c; }} obj.c=5;	class Product {{ public int c; }} obj.c=5;	Make field public.	Java
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
{{"name":"value" "id":57}}	{{"name":"value", "id":57}}	Add comma.	JSON
if (data = 75)	if (data == 75)	Use ==.	C++
data[47]	if (length(data) >= 47) data[47]	Check length.	R
SELECT * FROM items WHRE email=5;	SELECT * FROM items WHERE email=5;	Fix WHERE.	SQL
void process(); int main(){{process();}}	void process(); // prototype int main(){{process();}}	Declare before use.	C++
if x > 93 print('output')	if x > 93: print('output')	Colon missing after if.	Python
#main {{ color: red; }}	#main {{ color: red; }}	Correct.	CSS
var data int = 'test'	var data string = 'test'	Type mismatch.	Go
if foo = 31	if foo == 31	Use ==.	Ruby

if bar = 4

if bar == 4

Use ==.

MATLAB

raise 'message'

raise Exception('message')

Raise needs an exception class.

Python

cin >> z cout << z;

cin >> z; cout << z;

Add semicolon.

C++

String z = 'world';

String z = "world";

Double quotes.

Java

<ul><li>world<li>data</ul>

<ul><li>world</li><li>data</li></ul>

Close li.

HTML

ArrayList list = new ArrayList();

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

Use generics.

Java

'result' + 47

'result' + 47.to_s

Convert int.

Ruby

function handle() {{ return {{key:'output'}} }}

function handle() {{ return {{key:'output'}}; }}

Return object on same line.

JavaScript

list: - item1 - item2

Correct.

YAML

def compute(count): return count + 1

Correct.

Python

if (a = 58) {{}}

if (a == 58) {{}}

Use ==.

Kotlin

$values[43] = 5;

if (isset($values[43])) $values[43] = 5;

Check existence.

PHP

.Person {{ color: red; }}

Correct.

CSS

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

Correct.

Python

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

let x: i32 = "result";

let x: &str = "result";

Type mismatch.

Rust

let z = 'data'

let z = "data"

Double quotes.

Swift

function baz(): void {{ return 28; }}

function baz(): number {{ return 28; }}

Return type mismatch.

TypeScript

if result = 78

if result == 78

Use ==.

Go

DELETE FROM orders WHERE name=59

DELETE FROM orders WHERE name=59;

Add semicolon.

SQL

let mut x=37; let ref1=&mut x; let ref2=&mut x;

let mut x=37; {{ let ref1=&mut x; }} let ref2=&mut x;

Only one mutable borrow.

Rust

const person:Person = {{name:'data'}};

const person:Person = {{name:'data', age:37}};

Add missing property.

TypeScript

UPDATE orders SET age='message' WHERE status=8

UPDATE orders SET age='message' WHERE status=8;

Add semicolon.

SQL

["world", 96]

Correct.

JSON

data(87)

if length(data) >= 87, data(87), end

Check length.

MATLAB

let y: number | null = null; y.toFixed(2);

let y: number | null = null; if(y!==null) y.toFixed(2);

Null check.

TypeScript

Use CSS.

HTML

if x = 93 {{}}

if x == 93 {{}}

Use ==.

Swift

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(42);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(42, () => console.log('listening'));

Add callback.

Node.js

jwt.sign({{id:24}}, 'key');

jwt.sign({{id:24}}, 'key', {{expiresIn:'15m'}});

Add expiration.

Node.js

if item > 10 puts 'message'

if item > 10 puts 'message' end

Add 'end'.

Ruby

if x = 42:

if x == 42:

Use == for comparison.

Python

Product.save();

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

Handle promise.

Node.js

b = 60

b=60

No spaces.

Shell

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

function render() {{ echo 'hello'; }}

Correct.

PHP

SELECT id role FROM users;

SELECT id, role FROM users;

Add comma.

SQL

if (item = 59) {{}}

if (item == 59) {{}}

Use ==.

Java

if (a = 66)

if (a == 66)

Use ==.

R

c = world

c = 'world'

Quote strings.

Python

values[19]

if values.indices.contains(19) {{ values[19] }}

Check index.

Swift

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

Correct.

Java

for (int i=0; i<34; i++) {{}}

Correct.

Java

System.out.println('world')

System.out.println('world');

Add semicolon.

Java

Use double quotes.

JSON

<hr>

Self-closing.

HTML

div {{ color=green; }}

div {{ color: green; }}

Use colon.

CSS

// comment

/* comment */

Use /* */.

CSS

h1 {{ font-size:85px color:blue; }}

h1 {{ font-size:85px; color:blue; }}

Add semicolon.

CSS

'12' + 71

12 + 71

Avoid string coercion.

JavaScript

Use style attribute.

CSS

val count: Int = 'world'

val count: String = 'world'

Fix type.

Kotlin

Remove trailing comma.

JSON

'result' + 66

'result' + str(66)

Can't add int to string.

Python

<person><desc>data</desc><desc>84</desc></person

Add closing >.

XML

if ($z = 47)

if ($z == 47)

Use ==.

Perl

package main func main() {{}}

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

Import needed.

Go

disp('message')

Correct.

MATLAB

Add rel for security.

HTML

[2, 6, 56

[2, 6, 56]

Close bracket.

Ruby

match result {{ 1 => {{}} }}

match result {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

Nest properly.

HTML

$index = 2; if ($index = 2) {{}}

$index = 2; if ($index == 2) {{}}

Use ==.

PHP

if [ $foo = 24 ]; then

if [ "$foo" = 24 ]; then

Quote variable.

Shell

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

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

Throw Error objects.

JavaScript

handle

handle()

Add parentheses.

Swift

if ($y = 72) {{}}

if ($y -eq 72) {{}}

Use -eq.

PowerShell

<p>result <b>hello</p></b>

<p>result <b>hello</b></p>

Nest properly.

HTML

function baz(a:string){{return a;}} baz(70);

function baz(a:string){{return a;}} baz('data');

Pass correct type.

TypeScript

baz

baz()

Add parentheses.

Kotlin

arr.forEach(function(index) {{ console.log(index); }})

arr.forEach((index) => {{ console.log(index); }})

Arrow functions are cleaner.

JavaScript

int list[44]; list[44]=5;

int list[44]; if(44<44){{}} else list[44]=5;

Bounds check.

C++

Write-Host 'data'

Correct.

PowerShell

WHERE status = '28'

WHERE status = 28

Don't quote integer.

SQL

fmt.Println 'output'

fmt.Println('output')

Missing parentheses.

Go

cin >> result;

int result; cin >> result;

Declare variable.

C++

int* obj = nullptr; *obj=5;

int* obj = new int; *obj=5;

Allocate memory.

C++

value: world name: data,

value: world name: data

Remove comma.

YAML

<?php // code ?>

Correct.

PHP

my @arr = (90,43,25);

Correct.

Perl

Add alt text.

HTML

class Order {{ int foo; }};

class Order {{ public: int foo; }};

Make public.

C++

fn bar() -> i32 {{ 57 }}

Correct.

Rust

int[] list = new int[8]; list[8] = 5;

int[] list = new int[8]; if (8 < list.length) list[8] = 5;

Check bounds.

Java

class = 'hello'

class_name = 'hello'

'class' is a keyword.

Python

INSERT INTO items VALUES ('test',83)

INSERT INTO items (name, role) VALUES ('test',83);

Specify columns.

SQL

for foo in range(12) print(foo)

for foo in range(12): print(foo)

Colon after for.

Python

else print('message')

else: print('message')

Colon after else.

Python

Colon missing.

Python

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

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

Make field public.

Java

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

Correct.

Shell

Add comma.

JSON

if (data = 75)

if (data == 75)

Use ==.

C++

data[47]

if (length(data) >= 47) data[47]

Check length.

R

SELECT * FROM items WHRE email=5;

SELECT * FROM items WHERE email=5;

Fix WHERE.

SQL

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

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

Declare before use.

C++

if x > 93 print('output')

if x > 93: print('output')

Colon missing after if.

Python

#main {{ color: red; }}

Correct.

CSS

var data int = 'test'

var data string = 'test'

Type mismatch.

Go

if foo = 31

if foo == 31

Use ==.

Ruby