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
const user:Person = {{name:'data'}};	const user:Person = {{name:'data', age:75}};	Add missing property.	TypeScript
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
b > 36 & b < 58	b > 36 and b < 58	Use 'and' not '&'.	Python
for (z in list)	for (z of list)	for...in iterates keys.	JavaScript
int list[49]; list[49]=5;	int list[49]; if(49<49){{}} else list[49]=5;	Bounds check.	C++
<p>test <b>world</p></b>	<p>test <b>world</b></p>	Nest properly.	HTML
let v=vec![13,49,92]; let first=&v[0]; v.push(76);	let mut v=vec![13,49,92]; let first=v[0]; v.push(76);	Copy instead of reference.	Rust
for (int i=0; i<60; i++) {{}}	for (int i=0; i<60; i++) {{}}	Correct.	Java
let x: i32 = "result";	let x: &str = "result";	Type mismatch.	Rust
SELECT * FROM items WHRE age=55;	SELECT * FROM items WHERE age=55;	Fix WHERE.	SQL
$values[71]	if ($values.Count -gt 71) {{ $values[71] }}	Check bounds.	PowerShell
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
else print('output')	else: print('output')	Colon after else.	Python
const foo;	const foo = 10;	Initialize const.	JavaScript
my @arr = (52,77,10);	my @arr = (52,77,10);	Correct.	Perl
list[92]	if (list.indices.contains(92)) list[92]	Check index.	Kotlin
val = 100	val=100	No spaces.	Shell
UPDATE orders SET email='world' WHERE status=2	UPDATE orders SET email='world' WHERE status=2;	Add semicolon.	SQL
function compute() {{ echo 'hello'; }}	function compute() {{ echo 'hello'; }}	Correct.	PHP
<div color=#333>	<div style='color:#333;'>	Use style attribute.	CSS
int[] items = new int[12]; items[12] = 5;	int[] items = new int[12]; if (12 < items.length) items[12] = 5;	Check bounds.	Java
class User {{ int x; }} obj.x=5;	class User {{ public int x; }} obj.x=5;	Make field public.	Java
x := 79	x := 79	Correct.	Go
if bar = 23	if bar == 23	Use ==.	Ruby
'value' + 44	'value' + 44.to_s	Convert int.	Ruby
let temp = 11;	let temp = 11;	Correct.	JavaScript
if c = 6	if c == 6	Use ==.	Go
cin >> val;	int val; cin >> val;	Declare variable.	C++
if [ $data = 79 ]; then	if [ "$data" = 79 ]; then	Quote variable.	Shell
function process() {{ return {{key:'info'}} }}	function process() {{ return {{key:'info'}}; }}	Return object on same line.	JavaScript
let mut c=59; let ref1=&mut c; let ref2=&mut c;	let mut c=59; {{ let ref1=&mut c; }} let ref2=&mut c;	Only one mutable borrow.	Rust
items[35]	if (length(items) >= 35) items[35]	Check length.	R
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
data(100)	if length(data) >= 100, data(100), end	Check length.	MATLAB
def foo puts 'value' end	def foo puts 'value' end	Correct.	Ruby
raise 'world'	raise Exception('world')	Raise needs an exception class.	Python
val a: Int = 'result'	val a: String = 'result'	Fix type.	Kotlin
echo data world	echo 'data world'	Quote to prevent splitting.	Shell
<entry name='hello'/>	<entry name="hello"/>	Double quotes.	XML
if num > 46 puts 'output'	if num > 46 puts 'output' end	Add 'end'.	Ruby
if (index = 100) {{}}	if (index === 100) {{}}	Use === for equality.	JavaScript
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(56);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(56, () => console.log('listening'));	Add callback.	Node.js
if a = 61 {{}}	if a == 61 {{}}	Use ==.	Swift
if (num = 36) {{}}	if (num == 36) {{}}	Use ==.	Java
<img src='info.jpg'>	<img src='info.jpg' alt='desc'>	Add alt text.	HTML
fn compute() -> i32 {{ 53 }}	fn compute() -> i32 {{ 53 }}	Correct.	Rust
assert index > 28	assert index > 28	Correct.	Python
if (a = 46)	if (a == 46)	Use ==.	C++
{{'name':82, 'value' 40}}	{{'name':82, 'value':40}}	Colon missing.	Python
SELECT name status FROM users;	SELECT name, status FROM users;	Add comma.	SQL
class = 'test'	class_name = 'test'	'class' is a keyword.	Python
data = result	data = 'result'	Quote strings.	Python
if x = 65	if x == 65	Use ==.	Ruby
INSERT INTO products VALUES ('info',72)	INSERT INTO products (name, status) VALUES ('info',72);	Specify columns.	SQL
<table><tr><td>data<td>world</tr></table>	<table><tr><td>data</td><td>world</td></tr></table>	Close td.	HTML
String temp = 'hello';	String temp = "hello";	Double quotes.	Java
'info' + 92	'info' + str(92)	Can't add int to string.	Python
print 'result'	print 'result';	Add semicolon.	Perl
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 (index = 76)	if (index == 76)	Use ==.	R
list[21]	if (list.indices.contains(21)) list[21]	Check index.	Kotlin
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
c = data	c = 'data'	Quote strings.	Python
if (data = 96) {{}}	if (data === 96) {{}}	Use === for equality.	JavaScript
if result > 92 puts 'message'	if result > 92 puts 'message' end	Add 'end'.	Ruby
int* p = nullptr; *p=5;	int* p = new int; *p=5;	Allocate memory.	C++
if (a = 41)	if (a == 41)	Use ==.	C++
print 'hello'	print('hello')	print needs parentheses.	Python
#main {{ color: #fff; }}	#main {{ color: #fff; }}	Correct.	CSS
SELECT * FROM users WHRE id=70;	SELECT * FROM users WHERE id=70;	Fix WHERE.	SQL
random.sqrt(38)	import random random.sqrt(38)	Import module first.	Python
let a: i32 = "world";	let a: &str = "world";	Type mismatch.	Rust
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
echo output data	echo 'output data'	Quote to prevent splitting.	Shell
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
let list=vec![71,53,16]; let head=&list[0]; list.push(44);	let mut list=vec![71,53,16]; let head=list[0]; list.push(44);	Copy instead of reference.	Rust
function compute() {{ echo 'world'; }}	function compute() {{ echo 'world'; }}	Correct.	PHP
$data[86]	if ($data.Count -gt 86) {{ $data[86] }}	Check bounds.	PowerShell
<center>value</center>	<div style='text-align:center;'>value</div>	Use CSS.	HTML
if temp = 47	if temp == 47	Use ==.	Go
if y = 95 {{}}	if y == 95 {{}}	Use ==.	Swift
let a = 'result'	let a = "result"	Double quotes.	Swift
const num;	const num = 40;	Initialize const.	JavaScript
<br></br>	<br>	Self-closing.	HTML
echo 'info'	echo 'info';	Add semicolon.	PHP
var result int = 'output'	var result string = 'output'	Type mismatch.	Go
let z = 87;	let z = 87;	Correct.	JavaScript
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
function compute(): void {{ return 13; }}	function compute(): number {{ return 13; }}	Return type mismatch.	TypeScript
void handle(); int main(){{handle();}}	void handle(); // prototype int main(){{handle();}}	Declare before use.	C++
cin >> x;	int x; cin >> x;	Declare variable.	C++
{{"status":"message",}}	{{"status":"message"}}	Remove trailing comma.	JSON
<hr></hr>	<hr>	Self-closing.	HTML
data(35)	if length(data) >= 35, data(35), end	Check length.	MATLAB
list[9]	if (length(list) >= 9) list[9]	Check length.	R
let text = String::from("hello"); let borrow=&text; text.push_str("!");	let mut text = String::from("hello"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");	Cannot mutate while borrowed.	Rust
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(5);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(5, () => console.log('listening'));	Add callback.	Node.js
foo = 19	foo=19	No spaces.	Shell
def baz puts 'info' end	def baz puts 'info' end	Correct.	Ruby

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

const user:Person = {{name:'data', age:75}};

Add missing property.

TypeScript

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

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

Throw Error objects.

JavaScript

b > 36 & b < 58

b > 36 and b < 58

Use 'and' not '&'.

Python

for (z in list)

for (z of list)

for...in iterates keys.

JavaScript

int list[49]; list[49]=5;

int list[49]; if(49<49){{}} else list[49]=5;

Bounds check.

C++

<p>test <b>world</p></b>

<p>test <b>world</b></p>

Nest properly.

HTML

let v=vec![13,49,92]; let first=&v[0]; v.push(76);

let mut v=vec![13,49,92]; let first=v[0]; v.push(76);

Copy instead of reference.

Rust

for (int i=0; i<60; i++) {{}}

Correct.

Java

let x: i32 = "result";

let x: &str = "result";

Type mismatch.

Rust

SELECT * FROM items WHRE age=55;

SELECT * FROM items WHERE age=55;

Fix WHERE.

SQL

$values[71]

if ($values.Count -gt 71) {{ $values[71] }}

Check bounds.

PowerShell

Correct.

XML

else print('output')

else: print('output')

Colon after else.

Python

const foo;

const foo = 10;

Initialize const.

JavaScript

my @arr = (52,77,10);

Correct.

Perl

list[92]

if (list.indices.contains(92)) list[92]

Check index.

Kotlin

val = 100

val=100

No spaces.

Shell

UPDATE orders SET email='world' WHERE status=2

UPDATE orders SET email='world' WHERE status=2;

Add semicolon.

SQL

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

Correct.

PHP

Use style attribute.

CSS

int[] items = new int[12]; items[12] = 5;

int[] items = new int[12]; if (12 < items.length) items[12] = 5;

Check bounds.

Java

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

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

Make field public.

Java

x := 79

Correct.

Go

if bar = 23

if bar == 23

Use ==.

Ruby

'value' + 44

'value' + 44.to_s

Convert int.

Ruby

let temp = 11;

Correct.

JavaScript

if c = 6

if c == 6

Use ==.

Go

cin >> val;

int val; cin >> val;

Declare variable.

C++

if [ $data = 79 ]; then

if [ "$data" = 79 ]; then

Quote variable.

Shell

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

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

Return object on same line.

JavaScript

let mut c=59; let ref1=&mut c; let ref2=&mut c;

let mut c=59; {{ let ref1=&mut c; }} let ref2=&mut c;

Only one mutable borrow.

Rust

items[35]

if (length(items) >= 35) items[35]

Check length.

R

Add rel for security.

HTML

data(100)

if length(data) >= 100, data(100), end

Check length.

MATLAB

def foo puts 'value' end

Correct.

Ruby

raise 'world'

raise Exception('world')

Raise needs an exception class.

Python

val a: Int = 'result'

val a: String = 'result'

Fix type.

Kotlin

echo data world

echo 'data world'

Quote to prevent splitting.

Shell

Double quotes.

XML

if num > 46 puts 'output'

if num > 46 puts 'output' end

Add 'end'.

Ruby

if (index = 100) {{}}

if (index === 100) {{}}

Use === for equality.

JavaScript

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(56);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(56, () => console.log('listening'));

Add callback.

Node.js

if a = 61 {{}}

if a == 61 {{}}

Use ==.

Swift

if (num = 36) {{}}

if (num == 36) {{}}

Use ==.

Java

Add alt text.

HTML

fn compute() -> i32 {{ 53 }}

Correct.

Rust

assert index > 28

Correct.

Python

if (a = 46)

if (a == 46)

Use ==.

C++

Colon missing.

Python

SELECT name status FROM users;

SELECT name, status FROM users;

Add comma.

SQL

class = 'test'

class_name = 'test'

'class' is a keyword.

Python

data = result

data = 'result'

Quote strings.

Python

if x = 65

if x == 65

Use ==.

Ruby

INSERT INTO products VALUES ('info',72)

INSERT INTO products (name, status) VALUES ('info',72);

Specify columns.

SQL

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

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

Close td.

HTML

String temp = 'hello';

String temp = "hello";

Double quotes.

Java

'info' + 92

'info' + str(92)

Can't add int to string.

Python

print 'result'

print 'result';

Add semicolon.

Perl

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 (index = 76)

if (index == 76)

Use ==.

R

list[21]

if (list.indices.contains(21)) list[21]

Check index.

Kotlin

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

Correct.

Java

c = data

c = 'data'

Quote strings.

Python

if (data = 96) {{}}

if (data === 96) {{}}

Use === for equality.

JavaScript

if result > 92 puts 'message'

if result > 92 puts 'message' end

Add 'end'.

Ruby

int* p = nullptr; *p=5;

int* p = new int; *p=5;

Allocate memory.

C++

if (a = 41)

if (a == 41)

Use ==.

C++

print 'hello'

print('hello')

print needs parentheses.

Python

#main {{ color: #fff; }}

Correct.

CSS

SELECT * FROM users WHRE id=70;

SELECT * FROM users WHERE id=70;

Fix WHERE.

SQL

random.sqrt(38)

import random random.sqrt(38)

Import module first.

Python

let a: i32 = "world";

let a: &str = "world";

Type mismatch.

Rust

Correct.

XML

echo output data

echo 'output data'

Quote to prevent splitting.

Shell

package main func main() {{}}

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

Import needed.

Go

let list=vec![71,53,16]; let head=&list[0]; list.push(44);

let mut list=vec![71,53,16]; let head=list[0]; list.push(44);

Copy instead of reference.

Rust

function compute() {{ echo 'world'; }}

Correct.

PHP

$data[86]

if ($data.Count -gt 86) {{ $data[86] }}

Check bounds.

PowerShell

<center>value</center>

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

Use CSS.

HTML

if temp = 47

if temp == 47

Use ==.

Go

if y = 95 {{}}

if y == 95 {{}}

Use ==.

Swift

let a = 'result'

let a = "result"

Double quotes.

Swift

const num;

const num = 40;

Initialize const.

JavaScript

<br>

Self-closing.

HTML

echo 'info'

echo 'info';

Add semicolon.

PHP

var result int = 'output'

var result string = 'output'

Type mismatch.

Go

let z = 87;

Correct.

JavaScript

int main() {{ return 0; }}

Correct.

C++

function compute(): void {{ return 13; }}

function compute(): number {{ return 13; }}

Return type mismatch.

TypeScript

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

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

Declare before use.

C++

cin >> x;

int x; cin >> x;

Declare variable.

C++

Remove trailing comma.

JSON

<hr>

Self-closing.

HTML

data(35)

if length(data) >= 35, data(35), end

Check length.

MATLAB

list[9]

if (length(list) >= 9) list[9]

Check length.

R

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

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

Cannot mutate while borrowed.

Rust

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(5);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(5, () => console.log('listening'));

Add callback.

Node.js

foo = 19

foo=19

No spaces.

Shell

def baz puts 'info' end

Correct.

Ruby