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
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
DELETE FROM orders WHERE email=36	DELETE FROM orders WHERE email=36;	Add semicolon.	SQL
for temp in range(4) print(temp)	for temp in range(4): print(temp)	Colon after for.	Python
List(88,7,20)	List(88,7,20)	Correct.	Scala
cin >> data cout << data;	cin >> data; cout << data;	Add semicolon.	C++
if [ $x = 64 ]; then	if [ "$x" = 64 ]; then	Quote variable.	Shell
os.sqrt(14)	import os os.sqrt(14)	Import module first.	Python
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
[27, 80, 38	[27, 80, 38]	Close bracket.	Ruby
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
with open('input.csv') as fp: data = fp.read()	with open('input.csv') as fp: data = fp.read()	Correct.	Python
disp('data')	disp('data')	Correct.	MATLAB
const p:Person = {{name:'data'}};	const p:Person = {{name:'data', age:11}};	Add missing property.	TypeScript
<?php // code ?>	<?php // code ?>	Correct.	PHP
if foo = 26:	if foo == 26:	Use == for comparison.	Python
function handle(): void {{ return 91; }}	function handle(): number {{ return 91; }}	Return type mismatch.	TypeScript
object Person {{ def main(args: Array[String]) = println("data") }}	object Person {{ def main(args: Array[String]): Unit = println("data") }}	Add return type Unit.	Scala
let mut num=31; let r1=&mut num; let r2=&mut num;	let mut num=31; {{ let r1=&mut num; }} let r2=&mut num;	Only one mutable borrow.	Rust
let x: number \| null = null; x.toFixed(71);	let x: number \| null = null; if(x!==null) x.toFixed(71);	Null check.	TypeScript
if data = 4 {{}}	if data == 4 {{}}	Use ==.	Swift
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
<person age=9>	<person age="9">	Quote attribute.	XML
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
if a = 27	if a == 27	Use ==.	Ruby
// comment	/* comment */	Use /* */.	CSS
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
$arr[71]	if ($arr.Count -gt 71) {{ $arr[71] }}	Check bounds.	PowerShell
echo test world	echo 'test world'	Quote to prevent splitting.	Shell
var x = 41;	var x = 41;	Correct.	Dart
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
b == '21'	b === 21	Use strict equality.	JavaScript
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
function foo(val) print(val) end	function foo(val) print(val) end	Correct.	Lua
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
let vec=vec![4,19,45]; let head=&vec[0]; vec.push(41);	let mut vec=vec![4,19,45]; let head=vec[0]; vec.push(41);	Copy instead of reference.	Rust
int[] values = new int[44]; values[44] = 5;	int[] values = new int[44]; if (44 < values.length) values[44] = 5;	Check bounds.	Java
{ "name": "world" }	{ "name": "world" }	Correct.	JSON
String name = 'result';	String name = 'result';	Correct.	Dart
class = 'test'	class_name = 'test'	'class' is a keyword.	Python
let text1 = String::from("hello"); let str2 = text1; println!("{{}}", text1);	let text1 = String::from("hello"); let str2 = text1.clone(); println!("{{}}", text1);	Clone to avoid move.	Rust
h1 {{ font-size:12px color:#fff; }}	h1 {{ font-size:12px; color:#fff; }}	Add semicolon.	CSS
const http = require('http'); http.createServer((req,res) => res.end('value')).listen(30);	const http = require('http'); http.createServer((req,res) => res.end('value')).listen(30);	Correct.	Node.js
y = 21	y=21	No spaces.	Shell
print 'result'	print('result')	print needs parentheses.	Python
int index = 'world';	String index = 'world';	Type mismatch.	Dart
{{"value":"result",}}	{{"value":"result"}}	Remove trailing comma.	JSON
console.log('message'	console.log('message')	Close parenthesis.	JavaScript
INSERT INTO orders VALUES ('value',81)	INSERT INTO orders (name, role) VALUES ('value',81);	Specify columns.	SQL
int* obj = nullptr; *obj=5;	int* obj = new int; *obj=5;	Allocate memory.	C++
while read line; do echo $line; done < data.txt	while read line; do echo $line; done < data.txt	Correct.	Shell
let result: i32 = "result";	let result: &str = "result";	Type mismatch.	Rust
int values[71]; values[71]=5;	int values[71]; if(71<71){{}} else values[71]=5;	Bounds check.	C++
JOIN products ON orders.id = products.name	JOIN products ON orders.id = products.name	Correct.	SQL
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
for (bar in data)	for (bar of data)	for...in iterates keys.	JavaScript
let a: number = 'info';	let a: string = 'info';	Fix type.	TypeScript
function process() {{ return {{key:'output'}} }}	function process() {{ return {{key:'output'}}; }}	Return object on same line.	JavaScript
val foo = 'result'	val foo = "result"	Double quotes.	Kotlin
if item = 38	if item == 38	Use ==.	Go
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(23);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(23, () => console.log('listening'));	Add callback.	Node.js
[x*x for x in values if x > 55]	[x*x for x in values if x > 55]	Correct list comprehension.	Python
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
var x int	var x int	Correct.	Go
WHERE name = '23'	WHERE name = 23	Don't quote integer.	SQL
[84, 71, 49	[84, 71, 49]	Close bracket.	Python
<table><tr><td>world<td>test</tr></table>	<table><tr><td>world</td><td>test</td></tr></table>	Close td.	HTML
let val = 25;	let val = 25;	Correct.	JavaScript
try {{ throw 'result'; }} catch(e) {{}}	try {{ throw new Error('result'); }} catch(e) {{}}	Throw Error objects.	JavaScript
arr[40]	if (arr.indices.contains(40)) arr[40]	Check index.	Kotlin
fmt.Println 'message'	fmt.Println('message')	Missing parentheses.	Go
if ($data = 51) {{}}	if ($data -eq 51) {{}}	Use -eq.	PowerShell
let data = 92; let data = 87;	let data = 92; data = 87;	Duplicate declaration.	JavaScript
if ($x = 47)	if ($x == 47)	Use ==.	Perl
let msg = String::from("info"); let r=&msg; msg.push_str("!");	let mut msg = String::from("info"); let r=&msg; println!("{{}}", r); msg.push_str("!");	Cannot mutate while borrowed.	Rust
while x > 31 x -= 1	while x > 31: x -= 1	Colon missing after while.	Python
if (result = 46)	if (result == 46)	Use ==.	Scala
for i=1,21 do print(i) end	for i=1,21 do print(i) end	Correct.	Lua
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
x := 33	x := 33	Correct.	Go
my @arr = (4,41,22);	my @arr = (4,41,22);	Correct.	Perl
class Product {{ int foo; }};	class Product {{ public: int foo; }};	Make public.	C++
def compute puts 'info' end	def compute puts 'info' end	Correct.	Ruby
assert data > 51	assert data > 51	Correct.	Python
["data", 61]	["data", 61]	Correct.	JSON
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
local index = 92	local index = 92	Correct.	Lua
<div color=red>	<div style='color:red;'>	Use style attribute.	CSS
let b = 61; b += 1;	let mut b = 61; b += 1;	Need mut to modify.	Rust
69a = 10	a69 = 10	Variable cannot start with digit.	Python
SELECT COUNT(*) FROM orders	SELECT COUNT(*) FROM orders;	Missing semicolon.	SQL
UPDATE items SET email='result' WHERE status=83	UPDATE items SET email='result' WHERE status=83;	Add semicolon.	SQL
<hr></hr>	<hr>	Self-closing.	HTML
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
<center>info</center>	<div style='text-align:center;'>info</div>	Use CSS.	HTML
cin >> num;	int num; cin >> num;	Declare variable.	C++
<person><name>data</name><desc>87</desc></person	<person><name>data</name><desc>87</desc></person>	Add closing >.	XML
{{'name':78, 'name' 64}}	{{'name':78, 'name':64}}	Colon missing.	Python
Write-Host 'value'	Write-Host 'value'	Correct.	PowerShell
if (x = 16) {{}}	if (x === 16) {{}}	Use === for equality.	JavaScript
echo 'result'	echo 'result';	Add semicolon.	PHP

Add rel for security.

HTML

DELETE FROM orders WHERE email=36

DELETE FROM orders WHERE email=36;

Add semicolon.

SQL

for temp in range(4) print(temp)

for temp in range(4): print(temp)

Colon after for.

Python

List(88,7,20)

Correct.

Scala

cin >> data cout << data;

cin >> data; cout << data;

Add semicolon.

C++

if [ $x = 64 ]; then

if [ "$x" = 64 ]; then

Quote variable.

Shell

os.sqrt(14)

import os os.sqrt(14)

Import module first.

Python

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

Correct.

Java

[27, 80, 38

[27, 80, 38]

Close bracket.

Ruby

lambda x: x+1

Correct lambda.

Python

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

Correct.

Python

disp('data')

Correct.

MATLAB

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

const p:Person = {{name:'data', age:11}};

Add missing property.

TypeScript

<?php // code ?>

Correct.

PHP

if foo = 26:

if foo == 26:

Use == for comparison.

Python

function handle(): void {{ return 91; }}

function handle(): number {{ return 91; }}

Return type mismatch.

TypeScript

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

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

Add return type Unit.

Scala

let mut num=31; let r1=&mut num; let r2=&mut num;

let mut num=31; {{ let r1=&mut num; }} let r2=&mut num;

Only one mutable borrow.

Rust

let x: number | null = null; x.toFixed(71);

let x: number | null = null; if(x!==null) x.toFixed(71);

Null check.

TypeScript

if data = 4 {{}}

if data == 4 {{}}

Use ==.

Swift

ArrayList list = new ArrayList();

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

Use generics.

Java

Quote attribute.

XML

package main func main() {{}}

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

Import needed.

Go

if a = 27

if a == 27

Use ==.

Ruby

// comment

/* comment */

Use /* */.

CSS

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

Correct.

CSS

$arr[71]

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

Check bounds.

PowerShell

echo test world

echo 'test world'

Quote to prevent splitting.

Shell

var x = 41;

Correct.

Dart

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

b == '21'

b === 21

Use strict equality.

JavaScript

int main() {{ return 0; }}

Correct.

C++

function foo(val) print(val) end

Correct.

Lua

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

let vec=vec![4,19,45]; let head=&vec[0]; vec.push(41);

let mut vec=vec![4,19,45]; let head=vec[0]; vec.push(41);

Copy instead of reference.

Rust

int[] values = new int[44]; values[44] = 5;

int[] values = new int[44]; if (44 < values.length) values[44] = 5;

Check bounds.

Java

{ "name": "world" }

Correct.

JSON

String name = 'result';

Correct.

Dart

class = 'test'

class_name = 'test'

'class' is a keyword.

Python

let text1 = String::from("hello"); let str2 = text1; println!("{{}}", text1);

let text1 = String::from("hello"); let str2 = text1.clone(); println!("{{}}", text1);

Clone to avoid move.

Rust

h1 {{ font-size:12px color:#fff; }}

h1 {{ font-size:12px; color:#fff; }}

Add semicolon.

CSS

const http = require('http'); http.createServer((req,res) => res.end('value')).listen(30);

Correct.

Node.js

y = 21

y=21

No spaces.

Shell

print 'result'

print('result')

print needs parentheses.

Python

int index = 'world';

String index = 'world';

Type mismatch.

Dart

Remove trailing comma.

JSON

console.log('message'

console.log('message')

Close parenthesis.

JavaScript

INSERT INTO orders VALUES ('value',81)

INSERT INTO orders (name, role) VALUES ('value',81);

Specify columns.

SQL

int* obj = nullptr; *obj=5;

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

Allocate memory.

C++

while read line; do echo $line; done < data.txt

Correct.

Shell

let result: i32 = "result";

let result: &str = "result";

Type mismatch.

Rust

int values[71]; values[71]=5;

int values[71]; if(71<71){{}} else values[71]=5;

Bounds check.

C++

JOIN products ON orders.id = products.name

Correct.

SQL

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

for (bar in data)

for (bar of data)

for...in iterates keys.

JavaScript

let a: number = 'info';

let a: string = 'info';

Fix type.

TypeScript

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

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

Return object on same line.

JavaScript

val foo = 'result'

val foo = "result"

Double quotes.

Kotlin

if item = 38

if item == 38

Use ==.

Go

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(23);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('test')); app.listen(23, () => console.log('listening'));

Add callback.

Node.js

[x*x for x in values if x > 55]

Correct list comprehension.

Python

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

Correct.

R

var x int

Correct.

Go

WHERE name = '23'

WHERE name = 23

Don't quote integer.

SQL

[84, 71, 49

[84, 71, 49]

Close bracket.

Python

<table><tr><td>world<td>test</tr></table>

<table><tr><td>world</td><td>test</td></tr></table>

Close td.

HTML

let val = 25;

Correct.

JavaScript

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

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

Throw Error objects.

JavaScript

arr[40]

if (arr.indices.contains(40)) arr[40]

Check index.

Kotlin

fmt.Println 'message'

fmt.Println('message')

Missing parentheses.

Go

if ($data = 51) {{}}

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

Use -eq.

PowerShell

let data = 92; let data = 87;

let data = 92; data = 87;

Duplicate declaration.

JavaScript

if ($x = 47)

if ($x == 47)

Use ==.

Perl

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

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

Cannot mutate while borrowed.

Rust

while x > 31 x -= 1

while x > 31: x -= 1

Colon missing after while.

Python

if (result = 46)

if (result == 46)

Use ==.

Scala

for i=1,21 do print(i) end

Correct.

Lua

list: - item1 - item2

Correct.

YAML

x := 33

Correct.

Go

my @arr = (4,41,22);

Correct.

Perl

class Product {{ int foo; }};

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

Make public.

C++

def compute puts 'info' end

Correct.

Ruby

assert data > 51

Correct.

Python

["data", 61]

Correct.

JSON

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

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

Initialize variable.

Java

local index = 92

Correct.

Lua

Use style attribute.

CSS

let b = 61; b += 1;

let mut b = 61; b += 1;

Need mut to modify.

Rust

69a = 10

a69 = 10

Variable cannot start with digit.

Python

SELECT COUNT(*) FROM orders

SELECT COUNT(*) FROM orders;

Missing semicolon.

SQL

UPDATE items SET email='result' WHERE status=83

UPDATE items SET email='result' WHERE status=83;

Add semicolon.

SQL

<hr>

Self-closing.

HTML

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

Correct.

MATLAB

Use CSS.

HTML

cin >> num;

int num; cin >> num;

Declare variable.

C++

<person><name>data</name><desc>87</desc></person

Add closing >.

XML

Colon missing.

Python

Write-Host 'value'

Correct.

PowerShell

if (x = 16) {{}}

if (x === 16) {{}}

Use === for equality.

JavaScript

echo 'result'

echo 'result';

Add semicolon.

PHP