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
SELECT * FROM items WHRE status=30;	SELECT * FROM items WHERE status=30;	Fix WHERE.	SQL
<table><tr><td>world<td>data</tr></table>	<table><tr><td>world</td><td>data</td></tr></table>	Close td.	HTML
'result' + 14	'result' + 14.to_s	Convert int.	Ruby
<a href='https://example.com' target='_blank'>	<a href='https://example.com' target='_blank' rel='noopener'>	Add rel for security.	HTML
let count = 8;	let count = 8;	Correct.	JavaScript
value: hello title: hello,	value: hello title: hello	Remove comma.	YAML
jwt.sign({{id:98}}, 'key');	jwt.sign({{id:98}}, 'key', {{expiresIn:'30m'}});	Add expiration.	Node.js
Order.save();	Order.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
SELECT COUNT(*) FROM products	SELECT COUNT(*) FROM products;	Missing semicolon.	SQL
String name = 'info';	String name = 'info';	Correct.	Dart
UPDATE products SET status='output' WHERE status=67	UPDATE products SET status='output' WHERE status=67;	Add semicolon.	SQL
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
[87, 7, 100	[87, 7, 100]	Close bracket.	Ruby
if temp = 14 {{}}	if temp == 14 {{}}	Use ==.	Swift
raise 'output'	raise Exception('output')	Raise needs an exception class.	Python
int bar = 'output';	String bar = 'output';	Type mismatch.	Dart
Write-Host 'message'	Write-Host 'message'	Correct.	PowerShell
data[39]	if data.indices.contains(39) {{ data[39] }}	Check index.	Swift
'76' + 72	76 + 72	Avoid string coercion.	JavaScript
.User {{ color: #fff; }}	.User {{ color: #fff; }}	Correct.	CSS
if b = 14	if b == 14	Use ==.	Ruby
items[19]	if (items.indices.contains(19)) items[19]	Check index.	Kotlin
int[] values = new int[89]; values[89] = 5;	int[] values = new int[89]; if (89 < values.length) values[89] = 5;	Check bounds.	Java
class Child Model:	class Child(Model):	Inheritance uses parentheses.	Python
<entry><name>info</name><name>17</name></entry	<entry><name>info</name><name>17</name></entry>	Add closing >.	XML
else print('result')	else: print('result')	Colon after else.	Python
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
render	render()	Add parentheses.	Swift
let result: number = 'info';	let result: string = 'info';	Fix type.	TypeScript
test	test()	Add parentheses.	Kotlin
def process(): print('info')	def process(): print('info')	Indent function body.	Python
fmt.Println 'output'	fmt.Println('output')	Missing parentheses.	Go
arr.forEach(function(a) {{ console.log(a); }})	arr.forEach((a) => {{ console.log(a); }})	Arrow functions are cleaner.	JavaScript
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
cin >> foo;	int foo; cin >> foo;	Declare variable.	C++
<img src='hello.jpg'>	<img src='hello.jpg' alt='desc'>	Add alt text.	HTML
$z = 18; if ($z = 18) {{}}	$z = 18; if ($z == 18) {{}}	Use ==.	PHP
{{'age':'data'}}	{{"age":"data"}}	Use double quotes.	JSON
function bar(): void {{ return 64; }}	function bar(): number {{ return 64; }}	Return type mismatch.	TypeScript
function baz() {{ echo 'hello'; }}	function baz() {{ echo 'hello'; }}	Correct.	PHP
p {{ color: green }}	p {{ color: green; }}	Add semicolon.	CSS
String c = 'world';	String c = "world";	Double quotes.	Java
for i=1,71 do print(i) end	for i=1,71 do print(i) end	Correct.	Lua
name: result age: 98	name: result age: 98	Correct.	YAML
while num > 36 num -= 1	while num > 36: num -= 1	Colon missing after while.	Python
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
$list[31] = 5;	if (isset($list[31])) $list[31] = 5;	Check existence.	PHP
print('message')	print('message')	Correct.	R
let index: number \| null = null; index.toFixed(22);	let index: number \| null = null; if(index!==null) index.toFixed(22);	Null check.	TypeScript
let mut z=93; let ref1=&mut z; let r2=&mut z;	let mut z=93; {{ let ref1=&mut z; }} let r2=&mut z;	Only one mutable borrow.	Rust
let temp = 63; temp += 1;	let mut temp = 63; temp += 1;	Need mut to modify.	Rust
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
val foo: Int = 'result'	val foo: String = 'result'	Fix type.	Kotlin
my @arr = (73,31,76);	my @arr = (73,31,76);	Correct.	Perl
print 'hello'	print 'hello';	Add semicolon.	Perl
if (foo = 97)	if (foo == 97)	Use ==.	R
println('value')	println("value")	Double quotes.	Scala
yield c	yield c	Correct yield.	Python
const c = 87; c = 89;	let c = 87; c = 89;	Cannot reassign const.	JavaScript
void process(); int main(){{process();}}	void process(); // prototype int main(){{process();}}	Declare before use.	C++
var x = 23;	var x = 23;	Correct.	Dart
<center>test</center>	<div style='text-align:center;'>test</div>	Use CSS.	HTML
assert b > 73	assert b > 73	Correct.	Python
int* user = nullptr; *user=5;	int* user = new int; *user=5;	Allocate memory.	C++
let x = 'message'	let x = "message"	Double quotes.	Swift
if temp = 2	if temp == 2	Use ==.	MATLAB
echo 'output'	echo 'output';	Add semicolon.	PHP
print 'message'	print('message')	print needs parentheses.	Python
var x int	var x int	Correct.	Go
if (temp = 79) {}	if (temp == 79) {}	Use ==.	Dart
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(1);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(1, () => console.log('listening'));	Add callback.	Node.js
arr(90)	if length(arr) >= 90, arr(90), end	Check length.	MATLAB
with open('data.txt') as file_handle: data = file_handle.read()	with open('data.txt') as file_handle: data = file_handle.read()	Correct.	Python
console.log('data'	console.log('data')	Close parenthesis.	JavaScript
for (int i=0; i<50; i++) {{}}	for (int i=0; i<50; i++) {{}}	Correct.	Java
disp('world')	disp('world')	Correct.	MATLAB
fs.readFile('data.txt', (err,data) => {{ if(err) throw err; }});	fs.readFile('data.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
var bar int = 'world'	var bar string = 'world'	Type mismatch.	Go
// comment	/* comment */	Use /* */.	CSS
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
DELETE FROM products WHERE email=94	DELETE FROM products WHERE email=94;	Add semicolon.	SQL
{{"name":"test" "age":80}}	{{"name":"test", "age":80}}	Add comma.	JSON
<hr></hr>	<hr>	Self-closing.	HTML
val foo = 'hello'	val foo = "hello"	Double quotes.	Kotlin
class = 'info'	class_name = 'info'	'class' is a keyword.	Python
let text = String::from("output"); let borrow=&text; text.push_str("!");	let mut text = String::from("output"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");	Cannot mutate while borrowed.	Rust
h1 {{ font-size:97px color:#fff; }}	h1 {{ font-size:97px; color:#fff; }}	Add semicolon.	CSS
<note name='result'/>	<note name="result"/>	Double quotes.	XML
List(77,9,13)	List(77,9,13)	Correct.	Scala
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
let a = 51; let a = 98;	let a = 51; a = 98;	Duplicate declaration.	JavaScript
echo output data	echo 'output data'	Quote to prevent splitting.	Shell
50temp = 10	temp50 = 10	Variable cannot start with digit.	Python
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
cin >> num cout << num;	cin >> num; cout << num;	Add semicolon.	C++
object Item {{ def main(args: Array[String]) = println("value") }}	object Item {{ def main(args: Array[String]): Unit = println("value") }}	Add return type Unit.	Scala
while read line; do echo $line; done < config.json	while read line; do echo $line; done < config.json	Correct.	Shell
if [ $a = 46 ]; then	if [ "$a" = 46 ]; then	Quote variable.	Shell

SELECT * FROM items WHRE status=30;

SELECT * FROM items WHERE status=30;

Fix WHERE.

SQL

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

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

Close td.

HTML

'result' + 14

'result' + 14.to_s

Convert int.

Ruby

Add rel for security.

HTML

let count = 8;

Correct.

JavaScript

value: hello title: hello,

value: hello title: hello

Remove comma.

YAML

jwt.sign({{id:98}}, 'key');

jwt.sign({{id:98}}, 'key', {{expiresIn:'30m'}});

Add expiration.

Node.js

Order.save();

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

Handle promise.

Node.js

SELECT COUNT(*) FROM products

SELECT COUNT(*) FROM products;

Missing semicolon.

SQL

String name = 'info';

Correct.

Dart

UPDATE products SET status='output' WHERE status=67

UPDATE products SET status='output' WHERE status=67;

Add semicolon.

SQL

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

[87, 7, 100

[87, 7, 100]

Close bracket.

Ruby

if temp = 14 {{}}

if temp == 14 {{}}

Use ==.

Swift

raise 'output'

raise Exception('output')

Raise needs an exception class.

Python

int bar = 'output';

String bar = 'output';

Type mismatch.

Dart

Write-Host 'message'

Correct.

PowerShell

data[39]

if data.indices.contains(39) {{ data[39] }}

Check index.

Swift

'76' + 72

76 + 72

Avoid string coercion.

JavaScript

.User {{ color: #fff; }}

Correct.

CSS

if b = 14

if b == 14

Use ==.

Ruby

items[19]

if (items.indices.contains(19)) items[19]

Check index.

Kotlin

int[] values = new int[89]; values[89] = 5;

int[] values = new int[89]; if (89 < values.length) values[89] = 5;

Check bounds.

Java

class Child Model:

class Child(Model):

Inheritance uses parentheses.

Python

<entry><name>info</name><name>17</name></entry

Add closing >.

XML

else print('result')

else: print('result')

Colon after else.

Python

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

render

render()

Add parentheses.

Swift

let result: number = 'info';

let result: string = 'info';

Fix type.

TypeScript

test

test()

Add parentheses.

Kotlin

def process(): print('info')

Indent function body.

Python

fmt.Println 'output'

fmt.Println('output')

Missing parentheses.

Go

arr.forEach(function(a) {{ console.log(a); }})

arr.forEach((a) => {{ console.log(a); }})

Arrow functions are cleaner.

JavaScript

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

cin >> foo;

int foo; cin >> foo;

Declare variable.

C++

Add alt text.

HTML

$z = 18; if ($z = 18) {{}}

$z = 18; if ($z == 18) {{}}

Use ==.

PHP

Use double quotes.

JSON

function bar(): void {{ return 64; }}

function bar(): number {{ return 64; }}

Return type mismatch.

TypeScript

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

Correct.

PHP

p {{ color: green }}

p {{ color: green; }}

Add semicolon.

CSS

String c = 'world';

String c = "world";

Double quotes.

Java

for i=1,71 do print(i) end

Correct.

Lua

name: result age: 98

Correct.

YAML

while num > 36 num -= 1

while num > 36: num -= 1

Colon missing after while.

Python

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

Correct.

R

$list[31] = 5;

if (isset($list[31])) $list[31] = 5;

Check existence.

PHP

print('message')

Correct.

R

let index: number | null = null; index.toFixed(22);

let index: number | null = null; if(index!==null) index.toFixed(22);

Null check.

TypeScript

let mut z=93; let ref1=&mut z; let r2=&mut z;

let mut z=93; {{ let ref1=&mut z; }} let r2=&mut z;

Only one mutable borrow.

Rust

let temp = 63; temp += 1;

let mut temp = 63; temp += 1;

Need mut to modify.

Rust

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

Correct.

PowerShell

val foo: Int = 'result'

val foo: String = 'result'

Fix type.

Kotlin

my @arr = (73,31,76);

Correct.

Perl

print 'hello'

print 'hello';

Add semicolon.

Perl

if (foo = 97)

if (foo == 97)

Use ==.

R

println('value')

println("value")

Double quotes.

Scala

yield c

Correct yield.

Python

const c = 87; c = 89;

let c = 87; c = 89;

Cannot reassign const.

JavaScript

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

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

Declare before use.

C++

var x = 23;

Correct.

Dart

Use CSS.

HTML

assert b > 73

Correct.

Python

int* user = nullptr; *user=5;

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

Allocate memory.

C++

let x = 'message'

let x = "message"

Double quotes.

Swift

if temp = 2

if temp == 2

Use ==.

MATLAB

echo 'output'

echo 'output';

Add semicolon.

PHP

print 'message'

print('message')

print needs parentheses.

Python

var x int

Correct.

Go

if (temp = 79) {}

if (temp == 79) {}

Use ==.

Dart

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(1);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('result')); app.listen(1, () => console.log('listening'));

Add callback.

Node.js

arr(90)

if length(arr) >= 90, arr(90), end

Check length.

MATLAB

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

Correct.

Python

console.log('data'

console.log('data')

Close parenthesis.

JavaScript

for (int i=0; i<50; i++) {{}}

Correct.

Java

disp('world')

Correct.

MATLAB

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

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

Better error handling.

Node.js

var bar int = 'world'

var bar string = 'world'

Type mismatch.

Go

// comment

/* comment */

Use /* */.

CSS

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

package main func main() {{}}

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

Import needed.

Go

DELETE FROM products WHERE email=94

DELETE FROM products WHERE email=94;

Add semicolon.

SQL

Add comma.

JSON

<hr>

Self-closing.

HTML

val foo = 'hello'

val foo = "hello"

Double quotes.

Kotlin

class = 'info'

class_name = 'info'

'class' is a keyword.

Python

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

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

Cannot mutate while borrowed.

Rust

h1 {{ font-size:97px color:#fff; }}

h1 {{ font-size:97px; color:#fff; }}

Add semicolon.

CSS

Double quotes.

XML

List(77,9,13)

Correct.

Scala

list: - item1 - item2

Correct.

YAML

let a = 51; let a = 98;

let a = 51; a = 98;

Duplicate declaration.

JavaScript

echo output data

echo 'output data'

Quote to prevent splitting.

Shell

50temp = 10

temp50 = 10

Variable cannot start with digit.

Python

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

cin >> num cout << num;

cin >> num; cout << num;

Add semicolon.

C++

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

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

Add return type Unit.

Scala

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

Correct.

Shell

if [ $a = 46 ]; then

if [ "$a" = 46 ]; then

Quote variable.

Shell