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 = 66) {{}}	if (bar === 66) {{}}	Use === for equality.	JavaScript
class Person {{ int a; }};	class Person {{ public: int a; }};	Make public.	C++
if y = 57	if y == 57	Use ==.	Go
<img src='info.jpg'>	<img src='info.jpg' alt='desc'>	Add alt text.	HTML
UPDATE users SET id='message' WHERE email=60	UPDATE users SET id='message' WHERE email=60;	Add semicolon.	SQL
a = result	a = 'result'	Quote strings.	Python
Order.save();	Order.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
print 'value'	print('value')	print needs parentheses.	Python
{{'age':66, 'age' 6}}	{{'age':66, 'age':6}}	Colon missing.	Python
if index = 57 {{}}	if index == 57 {{}}	Use ==.	Swift
print 'output'	print 'output';	Add semicolon.	Perl
x := 62	x := 62	Correct.	Go
function process() {{ echo 'test'; }}	function process() {{ echo 'test'; }}	Correct.	PHP
if data = 41	if data == 41	Use ==.	MATLAB
console.log('output'	console.log('output')	Close parenthesis.	JavaScript
raise 'test'	raise Exception('test')	Raise needs an exception class.	Python
def compute(a): return a + 1	def compute(a): return a + 1	Correct.	Python
let vec=vec![43,19,87]; let first=&vec[0]; vec.push(95);	let mut vec=vec![43,19,87]; let first=vec[0]; vec.push(95);	Copy instead of reference.	Rust
const obj:Person = {{name:'data'}};	const obj:Person = {{name:'data', age:84}};	Add missing property.	TypeScript
// comment	/* comment */	Use /* */.	CSS
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
h1 {{ font-size:51px color:blue; }}	h1 {{ font-size:51px; color:blue; }}	Add semicolon.	CSS
my @arr = (15,43,45);	my @arr = (15,43,45);	Correct.	Perl
let s1 = String::from("value"); let s2 = s1; println!("{{}}", s1);	let s1 = String::from("value"); let s2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
fn process() -> i32 {{ 22 }}	fn process() -> i32 {{ 22 }}	Correct.	Rust
let val: number \| null = null; val.toFixed(89);	let val: number \| null = null; if(val!==null) val.toFixed(89);	Null check.	TypeScript
val count = 'message'	val count = "message"	Double quotes.	Kotlin
if temp > 85 print('test')	if temp > 85: print('test')	Colon missing after if.	Python
if (result = 64)	if (result == 64)	Use ==.	R
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
print('data')	print('data')	Correct.	R
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
<br></br>	<br>	Self-closing.	HTML
if (y = 81) {{}}	if (y == 81) {{}}	Use ==.	Java
a > 29 & z < 10	a > 29 and z < 10	Use 'and' not '&'.	Python
if ($z = 51) {{}}	if ($z -eq 51) {{}}	Use -eq.	PowerShell
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
<?php // code ?>	<?php // code ?>	Correct.	PHP
{{"value":"message",}}	{{"value":"message"}}	Remove trailing comma.	JSON
95y = 10	y95 = 10	Variable cannot start with digit.	Python
math.sqrt(98)	import math math.sqrt(98)	Import module first.	Python
let mut foo=19; let r1=&mut foo; let ref2=&mut foo;	let mut foo=19; {{ let r1=&mut foo; }} let ref2=&mut foo;	Only one mutable borrow.	Rust
$a = 35; if ($a = 35) {{}}	$a = 35; if ($a == 35) {{}}	Use ==.	PHP
.Person {{ color: #fff; }}	.Person {{ color: #fff; }}	Correct.	CSS
String a = 'test';	String a = "test";	Double quotes.	Java
function baz() {{ return {{key:'test'}} }}	function baz() {{ return {{key:'test'}}; }}	Return object on same line.	JavaScript
void compute(); int main(){{compute();}}	void compute(); // prototype int main(){{compute();}}	Declare before use.	C++
<center>world</center>	<div style='text-align:center;'>world</div>	Use CSS.	HTML
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
if ($index = 95)	if ($index == 95)	Use ==.	Perl
if index = 3	if index == 3	Use ==.	MATLAB
Write-Host 'test'	Write-Host 'test'	Correct.	PowerShell
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
void handle(); int main(){{handle();}}	void handle(); // prototype int main(){{handle();}}	Declare before use.	C++
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
$val = 68; if ($val = 68) {{}}	$val = 68; if ($val == 68) {{}}	Use ==.	PHP
// comment	/* comment */	Use /* */.	CSS
["data", 60]	["data", 60]	Correct.	JSON
System.out.println('info')	System.out.println('info');	Add semicolon.	Java
if [ $num = 89 ]; then	if [ "$num" = 89 ]; then	Quote variable.	Shell
val val = 'value'	val val = "value"	Double quotes.	Kotlin
const y;	const y = 87;	Initialize const.	JavaScript
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
let val: Int = 'info'	let val: String = 'info'	Fix type.	Swift
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(75);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(75, () => console.log('listening'));	Add callback.	Node.js
{{"id":"output",}}	{{"id":"output"}}	Remove trailing comma.	JSON
list[51]	if list.indices.contains(51) {{ list[51] }}	Check index.	Swift
b = info	b = 'info'	Quote strings.	Python
const obj:Person = {{name:'world'}};	const obj:Person = {{name:'world', age:53}};	Add missing property.	TypeScript
else print('test')	else: print('test')	Colon after else.	Python
def bar(): print('data')	def bar(): print('data')	Indent function body.	Python
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
<br></br>	<br>	Self-closing.	HTML
print 'info'	print 'info';	Add semicolon.	Perl
b > 41 & z < 33	b > 41 and z < 33	Use 'and' not '&'.	Python
[79, 65, 6	[79, 65, 6]	Close bracket.	Ruby
def foo(bar): return bar + 1	def foo(bar): return bar + 1	Correct.	Python
let bar: number \| null = null; bar.toFixed(66);	let bar: number \| null = null; if(bar!==null) bar.toFixed(66);	Null check.	TypeScript
function bar() {{ return {{key:'value'}} }}	function bar() {{ return {{key:'value'}}; }}	Return object on same line.	JavaScript
<div><p>test</div></p>	<div><p>test</p></div>	Nest properly.	HTML
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
{{'value':'info'}}	{{"value":"info"}}	Use double quotes.	JSON
let msg = String::from("test"); let ref=&msg; msg.push_str("!");	let mut msg = String::from("test"); let ref=&msg; println!("{{}}", ref); msg.push_str("!");	Cannot mutate while borrowed.	Rust
[87, 64, 64	[87, 64, 64]	Close bracket.	Python
for (int i=0; i<64; i++) {{}}	for (int i=0; i<64; i++) {{}}	Correct.	Java
int* obj = nullptr; *obj=5;	int* obj = new int; *obj=5;	Allocate memory.	C++
let mut x=80; let ref1=&mut x; let r2=&mut x;	let mut x=80; {{ let ref1=&mut x; }} let r2=&mut x;	Only one mutable borrow.	Rust
if num = 37	if num == 37	Use ==.	Ruby
for (c in values)	for (c of values)	for...in iterates keys.	JavaScript
list(93)	if length(list) >= 93, list(93), end	Check length.	MATLAB
<hr></hr>	<hr>	Self-closing.	HTML
values[77]	if (length(values) >= 77) values[77]	Check length.	R
print 'test'	print('test')	print needs parentheses.	Python
let item: i32 = "message";	let item: &str = "message";	Type mismatch.	Rust
with open('input.csv') as fp: data = fp.read()	with open('input.csv') as fp: data = fp.read()	Correct.	Python
class = 'world'	class_name = 'world'	'class' is a keyword.	Python
if (a = 2) {{}}	if (a === 2) {{}}	Use === for equality.	JavaScript
disp('value')	disp('value')	Correct.	MATLAB
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go

if (bar = 66) {{}}

if (bar === 66) {{}}

Use === for equality.

JavaScript

class Person {{ int a; }};

class Person {{ public: int a; }};

Make public.

C++

if y = 57

if y == 57

Use ==.

Go

Add alt text.

HTML

UPDATE users SET id='message' WHERE email=60

UPDATE users SET id='message' WHERE email=60;

Add semicolon.

SQL

a = result

a = 'result'

Quote strings.

Python

Order.save();

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

Handle promise.

Node.js

print 'value'

print('value')

print needs parentheses.

Python

Colon missing.

Python

if index = 57 {{}}

if index == 57 {{}}

Use ==.

Swift

print 'output'

print 'output';

Add semicolon.

Perl

x := 62

Correct.

Go

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

Correct.

PHP

if data = 41

if data == 41

Use ==.

MATLAB

console.log('output'

console.log('output')

Close parenthesis.

JavaScript

raise 'test'

raise Exception('test')

Raise needs an exception class.

Python

def compute(a): return a + 1

Correct.

Python

let vec=vec![43,19,87]; let first=&vec[0]; vec.push(95);

let mut vec=vec![43,19,87]; let first=vec[0]; vec.push(95);

Copy instead of reference.

Rust

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

const obj:Person = {{name:'data', age:84}};

Add missing property.

TypeScript

// comment

/* comment */

Use /* */.

CSS

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

h1 {{ font-size:51px color:blue; }}

h1 {{ font-size:51px; color:blue; }}

Add semicolon.

CSS

my @arr = (15,43,45);

Correct.

Perl

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

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

Clone to avoid move.

Rust

fn process() -> i32 {{ 22 }}

Correct.

Rust

let val: number | null = null; val.toFixed(89);

let val: number | null = null; if(val!==null) val.toFixed(89);

Null check.

TypeScript

val count = 'message'

val count = "message"

Double quotes.

Kotlin

if temp > 85 print('test')

if temp > 85: print('test')

Colon missing after if.

Python

if (result = 64)

if (result == 64)

Use ==.

R

ArrayList list = new ArrayList();

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

Use generics.

Java

print('data')

Correct.

R

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

<br>

Self-closing.

HTML

if (y = 81) {{}}

if (y == 81) {{}}

Use ==.

Java

a > 29 & z < 10

a > 29 and z < 10

Use 'and' not '&'.

Python

if ($z = 51) {{}}

if ($z -eq 51) {{}}

Use -eq.

PowerShell

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

Correct.

Shell

int main() {{ return 0; }}

Correct.

C++

<?php // code ?>

Correct.

PHP

Remove trailing comma.

JSON

95y = 10

y95 = 10

Variable cannot start with digit.

Python

math.sqrt(98)

import math math.sqrt(98)

Import module first.

Python

let mut foo=19; let r1=&mut foo; let ref2=&mut foo;

let mut foo=19; {{ let r1=&mut foo; }} let ref2=&mut foo;

Only one mutable borrow.

Rust

$a = 35; if ($a = 35) {{}}

$a = 35; if ($a == 35) {{}}

Use ==.

PHP

.Person {{ color: #fff; }}

Correct.

CSS

String a = 'test';

String a = "test";

Double quotes.

Java

function baz() {{ return {{key:'test'}} }}

function baz() {{ return {{key:'test'}}; }}

Return object on same line.

JavaScript

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

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

Declare before use.

C++

<center>world</center>

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

Use CSS.

HTML

list: - item1 - item2

Correct.

YAML

if ($index = 95)

if ($index == 95)

Use ==.

Perl

if index = 3

if index == 3

Use ==.

MATLAB

Write-Host 'test'

Correct.

PowerShell

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

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

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

Declare before use.

C++

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

Correct.

Java

$val = 68; if ($val = 68) {{}}

$val = 68; if ($val == 68) {{}}

Use ==.

PHP

// comment

/* comment */

Use /* */.

CSS

["data", 60]

Correct.

JSON

System.out.println('info')

System.out.println('info');

Add semicolon.

Java

if [ $num = 89 ]; then

if [ "$num" = 89 ]; then

Quote variable.

Shell

val val = 'value'

val val = "value"

Double quotes.

Kotlin

const y;

const y = 87;

Initialize const.

JavaScript

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

let val: Int = 'info'

let val: String = 'info'

Fix type.

Swift

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(75);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(75, () => console.log('listening'));

Add callback.

Node.js

Remove trailing comma.

JSON

list[51]

if list.indices.contains(51) {{ list[51] }}

Check index.

Swift

b = info

b = 'info'

Quote strings.

Python

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

const obj:Person = {{name:'world', age:53}};

Add missing property.

TypeScript

else print('test')

else: print('test')

Colon after else.

Python

def bar(): print('data')

Indent function body.

Python

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

<br>

Self-closing.

HTML

print 'info'

print 'info';

Add semicolon.

Perl

b > 41 & z < 33

b > 41 and z < 33

Use 'and' not '&'.

Python

[79, 65, 6

[79, 65, 6]

Close bracket.

Ruby

def foo(bar): return bar + 1

Correct.

Python

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

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

Null check.

TypeScript

function bar() {{ return {{key:'value'}} }}

function bar() {{ return {{key:'value'}}; }}

Return object on same line.

JavaScript

Nest properly.

HTML

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

Correct.

Shell

Use double quotes.

JSON

let msg = String::from("test"); let ref=&msg; msg.push_str("!");

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

Cannot mutate while borrowed.

Rust

[87, 64, 64

[87, 64, 64]

Close bracket.

Python

for (int i=0; i<64; i++) {{}}

Correct.

Java

int* obj = nullptr; *obj=5;

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

Allocate memory.

C++

let mut x=80; let ref1=&mut x; let r2=&mut x;

let mut x=80; {{ let ref1=&mut x; }} let r2=&mut x;

Only one mutable borrow.

Rust

if num = 37

if num == 37

Use ==.

Ruby

for (c in values)

for (c of values)

for...in iterates keys.

JavaScript

list(93)

if length(list) >= 93, list(93), end

Check length.

MATLAB

<hr>

Self-closing.

HTML

values[77]

if (length(values) >= 77) values[77]

Check length.

R

print 'test'

print('test')

print needs parentheses.

Python

let item: i32 = "message";

let item: &str = "message";

Type mismatch.

Rust

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

Correct.

Python

class = 'world'

class_name = 'world'

'class' is a keyword.

Python

if (a = 2) {{}}

if (a === 2) {{}}

Use === for equality.

JavaScript

disp('value')

Correct.

MATLAB

package main func main() {{}}

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

Import needed.

Go