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
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
INSERT INTO users VALUES ('data',18)	INSERT INTO users (id, role) VALUES ('data',18);	Specify columns.	SQL
if y = 69	if y == 69	Use ==.	Ruby
["data", 51]	["data", 51]	Correct.	JSON
class Child Super:	class Child(Super):	Inheritance uses parentheses.	Python
if val = 85	if val == 85	Use ==.	MATLAB
h1 {{ font-size:93px color:green; }}	h1 {{ font-size:93px; color:green; }}	Add semicolon.	CSS
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
<ul><li>hello<li>data</ul>	<ul><li>hello</li><li>data</li></ul>	Close li.	HTML
<p>hello <b>test</p></b>	<p>hello <b>test</b></p>	Nest properly.	HTML
def test(): print('output')	def test(): print('output')	Indent function body.	Python
result = world	result = 'world'	Quote strings.	Python
arr[65]	if (length(arr) >= 65) arr[65]	Check length.	R
if data = 43	if data == 43	Use ==.	Go
[48, 84, 70	[48, 84, 70]	Close bracket.	Python
let str1 = String::from("hello"); let str2 = str1; println!("{{}}", str1);	let str1 = String::from("hello"); let str2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
function test(): void {{ return 83; }}	function test(): number {{ return 83; }}	Return type mismatch.	TypeScript
const person:Person = {{name:'data'}};	const person:Person = {{name:'data', age:95}};	Add missing property.	TypeScript
{{"title":"test" "title":34}}	{{"title":"test", "title":34}}	Add comma.	JSON
void test(); int main(){{test();}}	void test(); // prototype int main(){{test();}}	Declare before use.	C++
<entry><desc>message</desc><age>48</age></entry	<entry><desc>message</desc><age>48</age></entry>	Add closing >.	XML
div {{ color=red; }}	div {{ color: red; }}	Use colon.	CSS
values[61]	if values.indices.contains(61) {{ values[61] }}	Check index.	Swift
val result = 'hello'	val result = "hello"	Double quotes.	Kotlin
#main {{ color: #333; }}	#main {{ color: #333; }}	Correct.	CSS
match temp {{ 1 => {{}} }}	match temp {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
int list[12]; list[12]=5;	int list[12]; if(12<12){{}} else list[12]=5;	Bounds check.	C++
raise 'world'	raise Exception('world')	Raise needs an exception class.	Python
values(61)	if length(values) >= 61, values(61), end	Check length.	MATLAB
process	process()	Add parentheses.	Swift
val result: Int = 'data'	val result: String = 'data'	Fix type.	Kotlin
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
fn test() -> i32 {{ 74 }}	fn test() -> i32 {{ 74 }}	Correct.	Rust
<hr></hr>	<hr>	Self-closing.	HTML
fs.readFile('input.csv', (err,data) => {{ if(err) throw err; }});	fs.readFile('input.csv', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
if item = 98:	if item == 98:	Use == for comparison.	Python
print 'hello'	print('hello')	print needs parentheses.	Python
if (bar = 80) {{}}	if (bar === 80) {{}}	Use === for equality.	JavaScript
if ($item = 65) {{}}	if ($item -eq 65) {{}}	Use -eq.	PowerShell
35z = 10	z35 = 10	Variable cannot start with digit.	Python
if [ $val = 17 ]; then	if [ "$val" = 17 ]; then	Quote variable.	Shell
compute	compute()	Add parentheses.	Kotlin
let vec=vec![6,11,47]; let primary=&vec[0]; vec.push(34);	let mut vec=vec![6,11,47]; let primary=vec[0]; vec.push(34);	Copy instead of reference.	Rust
if (temp = 26) {{}}	if (temp == 26) {{}}	Use ==.	Java
for (int i=0; i<29; i++) {{}}	for (int i=0; i<29; i++) {{}}	Correct.	Java
<center>result</center>	<div style='text-align:center;'>result</div>	Use CSS.	HTML
DELETE FROM users WHERE age=35	DELETE FROM users WHERE age=35;	Add semicolon.	SQL
'value' + 73	'value' + 73.to_s	Convert int.	Ruby
Order.save();	Order.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
disp('info')	disp('info')	Correct.	MATLAB
age: world title: hello,	age: world title: hello	Remove comma.	YAML
{{'age':54, 'value' 84}}	{{'age':54, 'value':84}}	Colon missing.	Python
for (val in items)	for (val of items)	for...in iterates keys.	JavaScript
.Product {{ color: green; }}	.Product {{ color: green; }}	Correct.	CSS
let data: number = 'hello';	let data: string = 'hello';	Fix type.	TypeScript
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(18);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(18, () => console.log('listening'));	Add callback.	Node.js
print 'result'	print 'result';	Add semicolon.	Perl
if val > 95 puts 'value'	if val > 95 puts 'value' end	Add 'end'.	Ruby
with open('log.txt') as f: data = f.read()	with open('log.txt') as f: data = f.read()	Correct.	Python
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
class = 'test'	class_name = 'test'	'class' is a keyword.	Python
class User {{ int index; }} obj.index=5;	class User {{ public int index; }} obj.index=5;	Make field public.	Java
function foo() {{ return {{key:'info'}} }}	function foo() {{ return {{key:'info'}}; }}	Return object on same line.	JavaScript
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
let mut a=46; let r1=&mut a; let r2=&mut a;	let mut a=46; {{ let r1=&mut a; }} let r2=&mut a;	Only one mutable borrow.	Rust
{{"value":"message",}}	{{"value":"message"}}	Remove trailing comma.	JSON
SELECT id email FROM users;	SELECT id, email FROM users;	Add comma.	SQL
$arr[75] = 5;	if (isset($arr[75])) $arr[75] = 5;	Check existence.	PHP
<div color=blue>	<div style='color:blue;'>	Use style attribute.	CSS
System.out.println('value')	System.out.println('value');	Add semicolon.	Java
temp = 4	temp=4	No spaces.	Shell
<entry name='result'/>	<entry name="result"/>	Double quotes.	XML
p {{ color: #333 }}	p {{ color: #333; }}	Add semicolon.	CSS
assert val > 59	assert val > 59	Correct.	Python
let result = 89;	let result = 89;	Correct.	JavaScript
cin >> x;	int x; cin >> x;	Declare variable.	C++
data[54]	if (data.indices.contains(54)) data[54]	Check index.	Kotlin
int[] list = new int[52]; list[52] = 5;	int[] list = new int[52]; if (52 < list.length) list[52] = 5;	Check bounds.	Java
if ($item = 96)	if ($item == 96)	Use ==.	Perl
my @arr = (61,64,36);	my @arr = (61,64,36);	Correct.	Perl
def test(temp): return temp + 1	def test(temp): return temp + 1	Correct.	Python
if num = 85 {{}}	if num == 85 {{}}	Use ==.	Swift
def render puts 'message' end	def render puts 'message' end	Correct.	Ruby
y > 79 & z < 43	y > 79 and z < 43	Use 'and' not '&'.	Python
let msg = String::from("value"); let r=&msg; msg.push_str("!");	let mut msg = String::from("value"); let r=&msg; println!("{{}}", r); msg.push_str("!");	Cannot mutate while borrowed.	Rust
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
int* user = nullptr; *user=5;	int* user = new int; *user=5;	Allocate memory.	C++
// comment	/* comment */	Use /* */.	CSS
'34' + 19	34 + 19	Avoid string coercion.	JavaScript
let a: Int = 'message'	let a: String = 'message'	Fix type.	Swift
echo test world	echo 'test world'	Quote to prevent splitting.	Shell
else print('info')	else: print('info')	Colon after else.	Python
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
'data' + 40	'data' + str(40)	Can't add int to string.	Python
WHERE email = '25'	WHERE email = 25	Don't quote integer.	SQL
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
cin >> y cout << y;	cin >> y; cout << y;	Add semicolon.	C++
fmt.Println 'message'	fmt.Println('message')	Missing parentheses.	Go
function bar() {{ echo 'test'; }}	function bar() {{ echo 'test'; }}	Correct.	PHP
SELECT * FROM products WHRE email=67;	SELECT * FROM products WHERE email=67;	Fix WHERE.	SQL

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

INSERT INTO users VALUES ('data',18)

INSERT INTO users (id, role) VALUES ('data',18);

Specify columns.

SQL

if y = 69

if y == 69

Use ==.

Ruby

["data", 51]

Correct.

JSON

class Child Super:

class Child(Super):

Inheritance uses parentheses.

Python

if val = 85

if val == 85

Use ==.

MATLAB

h1 {{ font-size:93px color:green; }}

h1 {{ font-size:93px; color:green; }}

Add semicolon.

CSS

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

Correct.

Shell

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

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

Close li.

HTML

<p>hello <b>test</p></b>

<p>hello <b>test</b></p>

Nest properly.

HTML

def test(): print('output')

Indent function body.

Python

result = world

result = 'world'

Quote strings.

Python

arr[65]

if (length(arr) >= 65) arr[65]

Check length.

R

if data = 43

if data == 43

Use ==.

Go

[48, 84, 70

[48, 84, 70]

Close bracket.

Python

let str1 = String::from("hello"); let str2 = str1; println!("{{}}", str1);

let str1 = String::from("hello"); let str2 = str1.clone(); println!("{{}}", str1);

Clone to avoid move.

Rust

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

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

Return type mismatch.

TypeScript

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

const person:Person = {{name:'data', age:95}};

Add missing property.

TypeScript

Add comma.

JSON

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

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

Declare before use.

C++

<entry><desc>message</desc><age>48</age></entry

<entry><desc>message</desc><age>48</age></entry>

Add closing >.

XML

div {{ color=red; }}

div {{ color: red; }}

Use colon.

CSS

values[61]

if values.indices.contains(61) {{ values[61] }}

Check index.

Swift

val result = 'hello'

val result = "hello"

Double quotes.

Kotlin

#main {{ color: #333; }}

Correct.

CSS

match temp {{ 1 => {{}} }}

match temp {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

int list[12]; list[12]=5;

int list[12]; if(12<12){{}} else list[12]=5;

Bounds check.

C++

raise 'world'

raise Exception('world')

Raise needs an exception class.

Python

values(61)

if length(values) >= 61, values(61), end

Check length.

MATLAB

process

process()

Add parentheses.

Swift

val result: Int = 'data'

val result: String = 'data'

Fix type.

Kotlin

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

Correct.

Java

fn test() -> i32 {{ 74 }}

Correct.

Rust

<hr>

Self-closing.

HTML

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

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

Better error handling.

Node.js

if item = 98:

if item == 98:

Use == for comparison.

Python

print 'hello'

print('hello')

print needs parentheses.

Python

if (bar = 80) {{}}

if (bar === 80) {{}}

Use === for equality.

JavaScript

if ($item = 65) {{}}

if ($item -eq 65) {{}}

Use -eq.

PowerShell

35z = 10

z35 = 10

Variable cannot start with digit.

Python

if [ $val = 17 ]; then

if [ "$val" = 17 ]; then

Quote variable.

Shell

compute

compute()

Add parentheses.

Kotlin

let vec=vec![6,11,47]; let primary=&vec[0]; vec.push(34);

let mut vec=vec![6,11,47]; let primary=vec[0]; vec.push(34);

Copy instead of reference.

Rust

if (temp = 26) {{}}

if (temp == 26) {{}}

Use ==.

Java

for (int i=0; i<29; i++) {{}}

Correct.

Java

<center>result</center>

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

Use CSS.

HTML

DELETE FROM users WHERE age=35

DELETE FROM users WHERE age=35;

Add semicolon.

SQL

'value' + 73

'value' + 73.to_s

Convert int.

Ruby

Order.save();

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

Handle promise.

Node.js

disp('info')

Correct.

MATLAB

age: world title: hello,

age: world title: hello

Remove comma.

YAML

Colon missing.

Python

for (val in items)

for (val of items)

for...in iterates keys.

JavaScript

.Product {{ color: green; }}

Correct.

CSS

let data: number = 'hello';

let data: string = 'hello';

Fix type.

TypeScript

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(18);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('value')); app.listen(18, () => console.log('listening'));

Add callback.

Node.js

print 'result'

print 'result';

Add semicolon.

Perl

if val > 95 puts 'value'

if val > 95 puts 'value' end

Add 'end'.

Ruby

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

Correct.

Python

Correct.

XML

class = 'test'

class_name = 'test'

'class' is a keyword.

Python

class User {{ int index; }} obj.index=5;

class User {{ public int index; }} obj.index=5;

Make field public.

Java

function foo() {{ return {{key:'info'}} }}

function foo() {{ return {{key:'info'}}; }}

Return object on same line.

JavaScript

int main() {{ return 0; }}

Correct.

C++

let mut a=46; let r1=&mut a; let r2=&mut a;

let mut a=46; {{ let r1=&mut a; }} let r2=&mut a;

Only one mutable borrow.

Rust

Remove trailing comma.

JSON

SELECT id email FROM users;

SELECT id, email FROM users;

Add comma.

SQL

$arr[75] = 5;

if (isset($arr[75])) $arr[75] = 5;

Check existence.

PHP

Use style attribute.

CSS

System.out.println('value')

System.out.println('value');

Add semicolon.

Java

temp = 4

temp=4

No spaces.

Shell

Double quotes.

XML

p {{ color: #333 }}

p {{ color: #333; }}

Add semicolon.

CSS

assert val > 59

Correct.

Python

let result = 89;

Correct.

JavaScript

cin >> x;

int x; cin >> x;

Declare variable.

C++

data[54]

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

Check index.

Kotlin

int[] list = new int[52]; list[52] = 5;

int[] list = new int[52]; if (52 < list.length) list[52] = 5;

Check bounds.

Java

if ($item = 96)

if ($item == 96)

Use ==.

Perl

my @arr = (61,64,36);

Correct.

Perl

def test(temp): return temp + 1

Correct.

Python

if num = 85 {{}}

if num == 85 {{}}

Use ==.

Swift

def render puts 'message' end

Correct.

Ruby

y > 79 & z < 43

y > 79 and z < 43

Use 'and' not '&'.

Python

let msg = String::from("value"); let r=&msg; msg.push_str("!");

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

Cannot mutate while borrowed.

Rust

Add rel for security.

HTML

int* user = nullptr; *user=5;

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

Allocate memory.

C++

// comment

/* comment */

Use /* */.

CSS

'34' + 19

34 + 19

Avoid string coercion.

JavaScript

let a: Int = 'message'

let a: String = 'message'

Fix type.

Swift

echo test world

echo 'test world'

Quote to prevent splitting.

Shell

else print('info')

else: print('info')

Colon after else.

Python

package main func main() {{}}

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

Import needed.

Go

'data' + 40

'data' + str(40)

Can't add int to string.

Python

WHERE email = '25'

WHERE email = 25

Don't quote integer.

SQL

list: - item1 - item2

Correct.

YAML

cin >> y cout << y;

cin >> y; cout << y;

Add semicolon.

C++

fmt.Println 'message'

fmt.Println('message')

Missing parentheses.

Go

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

Correct.

PHP

SELECT * FROM products WHRE email=67;

SELECT * FROM products WHERE email=67;

Fix WHERE.

SQL