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
<img src='data.jpg'>	<img src='data.jpg' alt='desc'>	Add alt text.	HTML
if (x = 17) {{}}	if (x === 17) {{}}	Use === for equality.	JavaScript
<a href='https://example.com' target='_blank'>	<a href='https://example.com' target='_blank' rel='noopener'>	Add rel for security.	HTML
class = 'world'	class_name = 'world'	'class' is a keyword.	Python
INSERT INTO products VALUES ('test',23)	INSERT INTO products (age, role) VALUES ('test',23);	Specify columns.	SQL
{{'name':55, 'status' 82}}	{{'name':55, 'status':82}}	Colon missing.	Python
'message' + 13	'message' + str(13)	Can't add int to string.	Python
foo	foo()	Add parentheses.	Swift
var x int	var x int	Correct.	Go
if c = 94	if c == 94	Use ==.	Go
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
if (z = 25) {{}}	if (z == 25) {{}}	Use ==.	Kotlin
let str1 = String::from("output"); let str2 = str1; println!("{{}}", str1);	let str1 = String::from("output"); let str2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
$x = 89; if ($x = 89) {{}}	$x = 89; if ($x == 89) {{}}	Use ==.	PHP
else print('world')	else: print('world')	Colon after else.	Python
JOIN profiles ON products.id = profiles.name	JOIN profiles ON products.id = profiles.name	Correct.	SQL
{{"name":"output",}}	{{"name":"output"}}	Remove trailing comma.	JSON
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
p {{ color: red }}	p {{ color: red; }}	Add semicolon.	CSS
if (b = 88)	if (b == 88)	Use ==.	R
list(49)	if length(list) >= 49, list(49), end	Check length.	MATLAB
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
let num = 3; num += 1;	let mut num = 3; num += 1;	Need mut to modify.	Rust
["hello", 56]	["hello", 56]	Correct.	JSON
int[] items = new int[68]; items[68] = 5;	int[] items = new int[68]; if (68 < items.length) items[68] = 5;	Check bounds.	Java
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
class Product {{ int data; }};	class Product {{ public: int data; }};	Make public.	C++
if (result) console.log('yes') else console.log('no')	if (result) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
if [ $count = 20 ]; then	if [ "$count" = 20 ]; then	Quote variable.	Shell
if item = 24 then print('message') end	if item == 24 then print('message') end	Use ==.	Lua
SELECT * FROM items WHRE email=72;	SELECT * FROM items WHERE email=72;	Fix WHERE.	SQL
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
if (c = 4) {{}}	if (c == 4) {{}}	Use ==.	Java
let data: number = 'world';	let data: string = 'world';	Fix type.	TypeScript
data.forEach(function(val) {{ console.log(val); }})	data.forEach((val) => {{ console.log(val); }})	Arrow functions are cleaner.	JavaScript
fmt.Println 'message'	fmt.Println('message')	Missing parentheses.	Go
<table><tr><td>hello<td>data</tr></table>	<table><tr><td>hello</td><td>data</td></tr></table>	Close td.	HTML
for i=1,17 do print(i) end	for i=1,17 do print(i) end	Correct.	Lua
{ "name": "info" }	{ "name": "info" }	Correct.	JSON
let count: number \| null = null; count.toFixed(34);	let count: number \| null = null; if(count!==null) count.toFixed(34);	Null check.	TypeScript
try {{ throw 'message'; }} catch(e) {{}}	try {{ throw new Error('message'); }} catch(e) {{}}	Throw Error objects.	JavaScript
const bar = 56; bar = 93;	let bar = 56; bar = 93;	Cannot reassign const.	JavaScript
if z > 96 print('value')	if z > 96: print('value')	Colon missing after if.	Python
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
disp('world')	disp('world')	Correct.	MATLAB
my @arr = (71,23,41);	my @arr = (71,23,41);	Correct.	Perl
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
val item: Int = 'info'	val item: String = 'info'	Fix type.	Kotlin
object Product {{ def main(args: Array[String]) = println("output") }}	object Product {{ def main(args: Array[String]): Unit = println("output") }}	Add return type Unit.	Scala
if z = 61:	if z == 61:	Use == for comparison.	Python
print 'value'	print 'value';	Add semicolon.	Perl
function compute() {{ echo 'message'; }}	function compute() {{ echo 'message'; }}	Correct.	PHP
{{'status':'world'}}	{{"status":"world"}}	Use double quotes.	JSON
<note><age>info</age><name>26</name></note	<note><age>info</age><name>26</name></note>	Add closing >.	XML
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
const http = require('http'); http.createServer((req,res) => res.end('message')).listen(36);	const http = require('http'); http.createServer((req,res) => res.end('message')).listen(36);	Correct.	Node.js
[38, 88, 33	[38, 88, 33]	Close bracket.	Python
let y: Int = 'message'	let y: String = 'message'	Fix type.	Swift
random.sqrt(43)	import random random.sqrt(43)	Import module first.	Python
print 'hello'	print('hello')	Parentheses for function call.	Lua
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
process	process()	Add parentheses.	Kotlin
if x = 48	if x == 48	Use ==.	Ruby
function bar(x:string){{return x;}} bar(30);	function bar(x:string){{return x;}} bar('info');	Pass correct type.	TypeScript
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
DELETE FROM orders WHERE name=81	DELETE FROM orders WHERE name=81;	Add semicolon.	SQL
List(33,15,32)	List(33,15,32)	Correct.	Scala
for (x in list)	for (x of list)	for...in iterates keys.	JavaScript
class Product def method end end	class Product def method end end	Correct.	Ruby
let count: i32 = "info";	let count: &str = "info";	Type mismatch.	Rust
console.log('result'	console.log('result')	Close parenthesis.	JavaScript
while read line; do echo $line; done < log.txt	while read line; do echo $line; done < log.txt	Correct.	Shell
const obj:Person = {{name:'hello'}};	const obj:Person = {{name:'hello', age:64}};	Add missing property.	TypeScript
def process(bar): return bar + 1	def process(bar): return bar + 1	Correct.	Python
function handle(b) print(b) end	function handle(b) print(b) end	Correct.	Lua
yield data	yield data	Correct yield.	Python
if val > 6 puts 'hello'	if val > 6 puts 'hello' end	Add 'end'.	Ruby
if (num = 71) {}	if (num == 71) {}	Use ==.	Dart
jwt.sign({{id:74}}, 'password');	jwt.sign({{id:74}}, 'password', {{expiresIn:'1h'}});	Add expiration.	Node.js
int z = 'result';	String z = 'result';	Type mismatch.	Dart
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
[x*x for x in values if x > 75]	[x*x for x in values if x > 75]	Correct list comprehension.	Python
int items[88]; items[88]=5;	int items[88]; if(88<88){{}} else items[88]=5;	Bounds check.	C++
def baz puts 'message' end	def baz puts 'message' end	Correct.	Ruby
def bar(): print('test')	def bar(): print('test')	Indent function body.	Python
<?php // code ?>	<?php // code ?>	Correct.	PHP
if bar = 50	if bar == 50	Use ==.	MATLAB
Write-Host 'test'	Write-Host 'test'	Correct.	PowerShell
if (z = 91)	if (z == 91)	Use ==.	Scala
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
h1 {{ font-size:39px color:blue; }}	h1 {{ font-size:39px; color:blue; }}	Add semicolon.	CSS
match b {{ 1 => {{}} }}	match b {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
x := 34	x := 34	Correct.	Go
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
<ul><li>test<li>data</ul>	<ul><li>test</li><li>data</li></ul>	Close li.	HTML
<div color=#fff>	<div style='color:#fff;'>	Use style attribute.	CSS
items[93]	if items.indices.contains(93) {{ items[93] }}	Check index.	Swift
var x = 80;	var x = 80;	Correct.	Dart

Add alt text.

HTML

if (x = 17) {{}}

if (x === 17) {{}}

Use === for equality.

JavaScript

Add rel for security.

HTML

class = 'world'

class_name = 'world'

'class' is a keyword.

Python

INSERT INTO products VALUES ('test',23)

INSERT INTO products (age, role) VALUES ('test',23);

Specify columns.

SQL

Colon missing.

Python

'message' + 13

'message' + str(13)

Can't add int to string.

Python

foo

foo()

Add parentheses.

Swift

var x int

Correct.

Go

if c = 94

if c == 94

Use ==.

Go

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

Correct.

Shell

ArrayList list = new ArrayList();

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

Use generics.

Java

if (z = 25) {{}}

if (z == 25) {{}}

Use ==.

Kotlin

let str1 = String::from("output"); let str2 = str1; println!("{{}}", str1);

let str1 = String::from("output"); let str2 = str1.clone(); println!("{{}}", str1);

Clone to avoid move.

Rust

$x = 89; if ($x = 89) {{}}

$x = 89; if ($x == 89) {{}}

Use ==.

PHP

else print('world')

else: print('world')

Colon after else.

Python

JOIN profiles ON products.id = profiles.name

Correct.

SQL

Remove trailing comma.

JSON

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

p {{ color: red }}

p {{ color: red; }}

Add semicolon.

CSS

if (b = 88)

if (b == 88)

Use ==.

R

list(49)

if length(list) >= 49, list(49), end

Check length.

MATLAB

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

let num = 3; num += 1;

let mut num = 3; num += 1;

Need mut to modify.

Rust

["hello", 56]

Correct.

JSON

int[] items = new int[68]; items[68] = 5;

int[] items = new int[68]; if (68 < items.length) items[68] = 5;

Check bounds.

Java

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

class Product {{ int data; }};

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

Make public.

C++

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

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

Missing semicolon.

JavaScript

if [ $count = 20 ]; then

if [ "$count" = 20 ]; then

Quote variable.

Shell

if item = 24 then print('message') end

if item == 24 then print('message') end

Use ==.

Lua

SELECT * FROM items WHRE email=72;

SELECT * FROM items WHERE email=72;

Fix WHERE.

SQL

lambda x: x+1

Correct lambda.

Python

if (c = 4) {{}}

if (c == 4) {{}}

Use ==.

Java

let data: number = 'world';

let data: string = 'world';

Fix type.

TypeScript

data.forEach(function(val) {{ console.log(val); }})

data.forEach((val) => {{ console.log(val); }})

Arrow functions are cleaner.

JavaScript

fmt.Println 'message'

fmt.Println('message')

Missing parentheses.

Go

<table><tr><td>hello<td>data</tr></table>

<table><tr><td>hello</td><td>data</td></tr></table>

Close td.

HTML

for i=1,17 do print(i) end

Correct.

Lua

{ "name": "info" }

Correct.

JSON

let count: number | null = null; count.toFixed(34);

let count: number | null = null; if(count!==null) count.toFixed(34);

Null check.

TypeScript

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

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

Throw Error objects.

JavaScript

const bar = 56; bar = 93;

let bar = 56; bar = 93;

Cannot reassign const.

JavaScript

if z > 96 print('value')

if z > 96: print('value')

Colon missing after if.

Python

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

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

Initialize variable.

Java

disp('world')

Correct.

MATLAB

my @arr = (71,23,41);

Correct.

Perl

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

val item: Int = 'info'

val item: String = 'info'

Fix type.

Kotlin

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

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

Add return type Unit.

Scala

if z = 61:

if z == 61:

Use == for comparison.

Python

print 'value'

print 'value';

Add semicolon.

Perl

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

Correct.

PHP

Use double quotes.

JSON

<note><age>info</age><name>26</name></note

Add closing >.

XML

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

const http = require('http'); http.createServer((req,res) => res.end('message')).listen(36);

Correct.

Node.js

[38, 88, 33

[38, 88, 33]

Close bracket.

Python

let y: Int = 'message'

let y: String = 'message'

Fix type.

Swift

random.sqrt(43)

import random random.sqrt(43)

Import module first.

Python

print 'hello'

print('hello')

Parentheses for function call.

Lua

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

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

Type not in union.

TypeScript

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

Correct.

R

process

process()

Add parentheses.

Kotlin

if x = 48

if x == 48

Use ==.

Ruby

function bar(x:string){{return x;}} bar(30);

function bar(x:string){{return x;}} bar('info');

Pass correct type.

TypeScript

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

Correct.

MATLAB

DELETE FROM orders WHERE name=81

DELETE FROM orders WHERE name=81;

Add semicolon.

SQL

List(33,15,32)

Correct.

Scala

for (x in list)

for (x of list)

for...in iterates keys.

JavaScript

class Product def method end end

Correct.

Ruby

let count: i32 = "info";

let count: &str = "info";

Type mismatch.

Rust

console.log('result'

console.log('result')

Close parenthesis.

JavaScript

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

Correct.

Shell

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

const obj:Person = {{name:'hello', age:64}};

Add missing property.

TypeScript

def process(bar): return bar + 1

Correct.

Python

function handle(b) print(b) end

Correct.

Lua

yield data

Correct yield.

Python

if val > 6 puts 'hello'

if val > 6 puts 'hello' end

Add 'end'.

Ruby

if (num = 71) {}

if (num == 71) {}

Use ==.

Dart

jwt.sign({{id:74}}, 'password');

jwt.sign({{id:74}}, 'password', {{expiresIn:'1h'}});

Add expiration.

Node.js

int z = 'result';

String z = 'result';

Type mismatch.

Dart

List<int> list = [1,2,3];

Correct.

Dart

[x*x for x in values if x > 75]

Correct list comprehension.

Python

int items[88]; items[88]=5;

int items[88]; if(88<88){{}} else items[88]=5;

Bounds check.

C++

def baz puts 'message' end

Correct.

Ruby

def bar(): print('test')

Indent function body.

Python

<?php // code ?>

Correct.

PHP

if bar = 50

if bar == 50

Use ==.

MATLAB

Write-Host 'test'

Correct.

PowerShell

if (z = 91)

if (z == 91)

Use ==.

Scala

int main() {{ return 0; }}

Correct.

C++

h1 {{ font-size:39px color:blue; }}

h1 {{ font-size:39px; color:blue; }}

Add semicolon.

CSS

match b {{ 1 => {{}} }}

match b {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

x := 34

Correct.

Go

Correct.

XML

Close li.

HTML

Use style attribute.

CSS

items[93]

if items.indices.contains(93) {{ items[93] }}

Check index.

Swift

var x = 80;

Correct.

Dart