Corpus-NZ/Code-Syntax-Expanded · Datasets at Hugging Face

wrong_code stringlengths 3 123	correct_code stringlengths 3 155	explanation stringclasses 101 values	language stringclasses 26 values
System.out.println('hello')	System.out.println('hello');	Add semicolon.	Java
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
{{"value":"info",}}	{{"value":"info"}}	Remove trailing comma.	JSON
<user name='world'/>	<user name="world"/>	Double quotes.	XML
String item = 'test';	String item = "test";	Double quotes.	Java
[x*x for x in data if x > 61]	[x*x for x in data if x > 61]	Correct list comprehension.	Python
var temp int = 'data'	var temp string = 'data'	Type mismatch.	Go
Order.save();	Order.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
let temp = 10;	let temp = 10;	Correct.	JavaScript
const http = require('http'); http.createServer((req,res) => res.end('test')).listen(27);	const http = require('http'); http.createServer((req,res) => res.end('test')).listen(27);	Correct.	Node.js
for (val in arr)	for (val of arr)	for...in iterates keys.	JavaScript
if (count = 42)	if (count == 42)	Use ==.	C++
Write-Host 'result'	Write-Host 'result'	Correct.	PowerShell
let val = 31; let val = 46;	let val = 31; val = 46;	Duplicate declaration.	JavaScript
if (num) console.log('yes') else console.log('no')	if (num) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
local num = 20	local num = 20	Correct.	Lua
print 'world'	print 'world';	Add semicolon.	Perl
WHERE id = '97'	WHERE id = 97	Don't quote integer.	SQL
val foo = 'message'	val foo = "message"	Double quotes.	Kotlin
'13' + 23	13 + 23	Avoid string coercion.	JavaScript
process	process()	Add parentheses.	Kotlin
println('data')	println("data")	Double quotes.	Scala
val c: Int = 'message'	val c: String = 'message'	Fix type.	Kotlin
echo 'output'	echo 'output';	Add semicolon.	PHP
let index = 'world'	let index = "world"	Double quotes.	Swift
["message", 96]	["message", 96]	Correct.	JSON
if temp = 66	if temp == 66	Use ==.	MATLAB
baz	baz()	Add parentheses.	Swift
raise 'hello'	raise Exception('hello')	Raise needs an exception class.	Python
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
while read line; do echo $line; done < config.json	while read line; do echo $line; done < config.json	Correct.	Shell
const data = 9; data = 41;	let data = 9; data = 41;	Cannot reassign const.	JavaScript
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
let a: i32 = "info";	let a: &str = "info";	Type mismatch.	Rust
print 'test'	print('test')	print needs parentheses.	Python
def test puts 'data' end	def test puts 'data' end	Correct.	Ruby
<br></br>	<br>	Self-closing.	HTML
if (item = 22) {}	if (item == 22) {}	Use ==.	Dart
var x = 45;	var x = 45;	Correct.	Dart
if val > 99 puts 'message'	if val > 99 puts 'message' end	Add 'end'.	Ruby
items[51]	if items.indices.contains(51) {{ items[51] }}	Check index.	Swift
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
match y {{ 1 => {{}} }}	match y {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
def bar(y): return y + 1	def bar(y): return y + 1	Correct.	Python
h1 {{ font-size:1px color:blue; }}	h1 {{ font-size:1px; color:blue; }}	Add semicolon.	CSS
<img src='hello.jpg'>	<img src='hello.jpg' alt='desc'>	Add alt text.	HTML
let s = String::from("test"); let borrow=&s; s.push_str("!");	let mut s = String::from("test"); let borrow=&s; println!("{{}}", borrow); s.push_str("!");	Cannot mutate while borrowed.	Rust
fn render() -> i32 {{ 7 }}	fn render() -> i32 {{ 7 }}	Correct.	Rust
console.log('result'	console.log('result')	Close parenthesis.	JavaScript
JOIN profiles ON items.id = profiles.id	JOIN profiles ON items.id = profiles.id	Correct.	SQL
if (bar = 25) {{}}	if (bar == 25) {{}}	Use ==.	Kotlin
let c: number = 'output';	let c: string = 'output';	Fix type.	TypeScript
else print('hello')	else: print('hello')	Colon after else.	Python
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
with open('log.txt') as f: data = f.read()	with open('log.txt') as f: data = f.read()	Correct.	Python
x := 93	x := 93	Correct.	Go
'output' + 64	'output' + str(64)	Can't add int to string.	Python
[13, 6, 45	[13, 6, 45]	Close bracket.	Ruby
print('hello')	print('hello')	Correct.	R
list(86)	if length(list) >= 86, list(86), end	Check length.	MATLAB
function compute(): void {{ return 56; }}	function compute(): number {{ return 56; }}	Return type mismatch.	TypeScript
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
<center>world</center>	<div style='text-align:center;'>world</div>	Use CSS.	HTML
disp('test')	disp('test')	Correct.	MATLAB
let vec=vec![62,53,29]; let head=&vec[0]; vec.push(100);	let mut vec=vec![62,53,29]; let head=vec[0]; vec.push(100);	Copy instead of reference.	Rust
yield val	yield val	Correct yield.	Python
if (data = 62) {{}}	if (data == 62) {{}}	Use ==.	Java
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
[79, 69, 44	[79, 69, 44]	Close bracket.	Python
DELETE FROM orders WHERE email=13	DELETE FROM orders WHERE email=13;	Add semicolon.	SQL
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
36bar = 10	bar36 = 10	Variable cannot start with digit.	Python
'result' + 80	'result' + 80.to_s	Convert int.	Ruby
void bar(); int main(){{bar();}}	void bar(); // prototype int main(){{bar();}}	Declare before use.	C++
values.forEach(function(result) {{ console.log(result); }})	values.forEach((result) => {{ console.log(result); }})	Arrow functions are cleaner.	JavaScript
object Order {{ def main(args: Array[String]) = println("data") }}	object Order {{ def main(args: Array[String]): Unit = println("data") }}	Add return type Unit.	Scala
num = 99	num=99	No spaces.	Shell
let temp: Int = 'value'	let temp: String = 'value'	Fix type.	Swift
p {{ color: blue }}	p {{ color: blue; }}	Add semicolon.	CSS
let bar: number \| null = null; bar.toFixed(69);	let bar: number \| null = null; if(bar!==null) bar.toFixed(69);	Null check.	TypeScript
$x = 30; if ($x = 30) {{}}	$x = 30; if ($x == 30) {{}}	Use ==.	PHP
fmt.Println 'world'	fmt.Println('world')	Missing parentheses.	Go
fs.readFile('config.json', (err,data) => {{ if(err) throw err; }});	fs.readFile('config.json', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
SELECT * FROM products WHRE email=52;	SELECT * FROM products WHERE email=52;	Fix WHERE.	SQL
if a = 93 {{}}	if a == 93 {{}}	Use ==.	Swift
if (foo = 97)	if (foo == 97)	Use ==.	Scala
print 'hello'	print('hello')	Parentheses for function call.	Lua
assert y > 25	assert y > 25	Correct.	Python
for index in range(49) print(index)	for index in range(49): print(index)	Colon after for.	Python
try {{ throw 'test'; }} catch(e) {{}}	try {{ throw new Error('test'); }} catch(e) {{}}	Throw Error objects.	JavaScript
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
<person age=75>	<person age="75">	Quote attribute.	XML
<?php // code ?>	<?php // code ?>	Correct.	PHP
if x = 4 then print('result') end	if x == 4 then print('result') end	Use ==.	Lua
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java

System.out.println('hello')

System.out.println('hello');

Add semicolon.

Java

list: - item1 - item2

Correct.

YAML

Remove trailing comma.

JSON

Double quotes.

XML

String item = 'test';

String item = "test";

Double quotes.

Java

[x*x for x in data if x > 61]

Correct list comprehension.

Python

var temp int = 'data'

var temp string = 'data'

Type mismatch.

Go

Order.save();

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

Handle promise.

Node.js

let temp = 10;

Correct.

JavaScript

const http = require('http'); http.createServer((req,res) => res.end('test')).listen(27);

Correct.

Node.js

for (val in arr)

for (val of arr)

for...in iterates keys.

JavaScript

if (count = 42)

if (count == 42)

Use ==.

C++

Write-Host 'result'

Correct.

PowerShell

let val = 31; let val = 46;

let val = 31; val = 46;

Duplicate declaration.

JavaScript

if (num) console.log('yes') else console.log('no')

if (num) console.log('yes'); else console.log('no');

Missing semicolon.

JavaScript

x = 5; if x > 3, disp('large'), end

Correct.

MATLAB

$x = 5; if ($x -eq 5) { Write-Host 'yes' }

Correct.

PowerShell

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

local num = 20

Correct.

Lua

print 'world'

print 'world';

Add semicolon.

Perl

WHERE id = '97'

WHERE id = 97

Don't quote integer.

SQL

val foo = 'message'

val foo = "message"

Double quotes.

Kotlin

'13' + 23

13 + 23

Avoid string coercion.

JavaScript

process

process()

Add parentheses.

Kotlin

println('data')

println("data")

Double quotes.

Scala

val c: Int = 'message'

val c: String = 'message'

Fix type.

Kotlin

echo 'output'

echo 'output';

Add semicolon.

PHP

let index = 'world'

let index = "world"

Double quotes.

Swift

["message", 96]

Correct.

JSON

if temp = 66

if temp == 66

Use ==.

MATLAB

baz

baz()

Add parentheses.

Swift

raise 'hello'

raise Exception('hello')

Raise needs an exception class.

Python

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

while read line; do echo $line; done < config.json

Correct.

Shell

const data = 9; data = 41;

let data = 9; data = 41;

Cannot reassign const.

JavaScript

@media screen {{ body {{}} }}

Correct.

CSS

let a: i32 = "info";

let a: &str = "info";

Type mismatch.

Rust

print 'test'

print('test')

print needs parentheses.

Python

def test puts 'data' end

Correct.

Ruby

<br>

Self-closing.

HTML

if (item = 22) {}

if (item == 22) {}

Use ==.

Dart

var x = 45;

Correct.

Dart

if val > 99 puts 'message'

if val > 99 puts 'message' end

Add 'end'.

Ruby

items[51]

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

Check index.

Swift

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

match y {{ 1 => {{}} }}

match y {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

def bar(y): return y + 1

Correct.

Python

h1 {{ font-size:1px color:blue; }}

h1 {{ font-size:1px; color:blue; }}

Add semicolon.

CSS

Add alt text.

HTML

let s = String::from("test"); let borrow=&s; s.push_str("!");

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

Cannot mutate while borrowed.

Rust

fn render() -> i32 {{ 7 }}

Correct.

Rust

console.log('result'

console.log('result')

Close parenthesis.

JavaScript

JOIN profiles ON items.id = profiles.id

Correct.

SQL

if (bar = 25) {{}}

if (bar == 25) {{}}

Use ==.

Kotlin

let c: number = 'output';

let c: string = 'output';

Fix type.

TypeScript

else print('hello')

else: print('hello')

Colon after else.

Python

package main func main() {{}}

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

Import needed.

Go

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

Correct.

Python

x := 93

Correct.

Go

'output' + 64

'output' + str(64)

Can't add int to string.

Python

[13, 6, 45

[13, 6, 45]

Close bracket.

Ruby

print('hello')

Correct.

R

list(86)

if length(list) >= 86, list(86), end

Check length.

MATLAB

function compute(): void {{ return 56; }}

function compute(): number {{ return 56; }}

Return type mismatch.

TypeScript

Add rel for security.

HTML

<center>world</center>

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

Use CSS.

HTML

disp('test')

Correct.

MATLAB

let vec=vec![62,53,29]; let head=&vec[0]; vec.push(100);

let mut vec=vec![62,53,29]; let head=vec[0]; vec.push(100);

Copy instead of reference.

Rust

yield val

Correct yield.

Python

if (data = 62) {{}}

if (data == 62) {{}}

Use ==.

Java

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

[79, 69, 44

[79, 69, 44]

Close bracket.

Python

DELETE FROM orders WHERE email=13

DELETE FROM orders WHERE email=13;

Add semicolon.

SQL

int main() {{ return 0; }}

Correct.

C++

36bar = 10

bar36 = 10

Variable cannot start with digit.

Python

'result' + 80

'result' + 80.to_s

Convert int.

Ruby

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

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

Declare before use.

C++

values.forEach(function(result) {{ console.log(result); }})

values.forEach((result) => {{ console.log(result); }})

Arrow functions are cleaner.

JavaScript

object Order {{ def main(args: Array[String]) = println("data") }}

object Order {{ def main(args: Array[String]): Unit = println("data") }}

Add return type Unit.

Scala

num = 99

num=99

No spaces.

Shell

let temp: Int = 'value'

let temp: String = 'value'

Fix type.

Swift

p {{ color: blue }}

p {{ color: blue; }}

Add semicolon.

CSS

let bar: number | null = null; bar.toFixed(69);

let bar: number | null = null; if(bar!==null) bar.toFixed(69);

Null check.

TypeScript

$x = 30; if ($x = 30) {{}}

$x = 30; if ($x == 30) {{}}

Use ==.

PHP

fmt.Println 'world'

fmt.Println('world')

Missing parentheses.

Go

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

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

Better error handling.

Node.js

SELECT * FROM products WHRE email=52;

SELECT * FROM products WHERE email=52;

Fix WHERE.

SQL

if a = 93 {{}}

if a == 93 {{}}

Use ==.

Swift

if (foo = 97)

if (foo == 97)

Use ==.

Scala

print 'hello'

print('hello')

Parentheses for function call.

Lua

assert y > 25

Correct.

Python

for index in range(49) print(index)

for index in range(49): print(index)

Colon after for.

Python

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

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

Throw Error objects.

JavaScript

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

Correct.

Shell

x <- 5; if (x > 3) print('large')

Correct.

R

type MyType = string | number; let x: MyType = true;

type MyType = string | number; let x: MyType = 'hello';

Type not in union.

TypeScript

Quote attribute.

XML

<?php // code ?>

Correct.

PHP

if x = 4 then print('result') end

if x == 4 then print('result') end

Use ==.

Lua

int x; System.out.println(x);

int x = 0; System.out.println(x);

Initialize variable.

Java