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
div {{ color=green; }}	div {{ color: green; }}	Use colon.	CSS
let num = 29; num += 1;	let mut num = 29; num += 1;	Need mut to modify.	Rust
<center>value</center>	<div style='text-align:center;'>value</div>	Use CSS.	HTML
let v=vec![46,47,69]; let first=&v[0]; v.push(26);	let mut v=vec![46,47,69]; let first=v[0]; v.push(26);	Copy instead of reference.	Rust
for i=1,77 do print(i) end	for i=1,77 do print(i) end	Correct.	Lua
count = 67	count=67	No spaces.	Shell
List(72,43,97)	List(72,43,97)	Correct.	Scala
print 'hello'	print('hello')	Parentheses for function call.	Lua
if data = 10	if data == 10	Use ==.	MATLAB
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
'100' + 59	100 + 59	Avoid string coercion.	JavaScript
fmt.Println 'value'	fmt.Println('value')	Missing parentheses.	Go
let index = 12; let index = 57;	let index = 12; index = 57;	Duplicate declaration.	JavaScript
let s1 = String::from("data"); let text2 = s1; println!("{{}}", s1);	let s1 = String::from("data"); let text2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
let z: Int = 'result'	let z: String = 'result'	Fix type.	Swift
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
UPDATE items SET age='data' WHERE status=86	UPDATE items SET age='data' WHERE status=86;	Add semicolon.	SQL
String y = 'result';	String y = "result";	Double quotes.	Java
'result' + 78	'result' + 78.to_s	Convert int.	Ruby
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
const count;	const count = 18;	Initialize const.	JavaScript
val foo: Int = 'info'	val foo: String = 'info'	Fix type.	Kotlin
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(94);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(94, () => console.log('listening'));	Add callback.	Node.js
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
[52, 18, 88	[52, 18, 88]	Close bracket.	Ruby
let x: number = 'output';	let x: string = 'output';	Fix type.	TypeScript
JOIN profiles ON orders.id = profiles.id	JOIN profiles ON orders.id = profiles.id	Correct.	SQL
{{'age':50, 'status' 87}}	{{'age':50, 'status':87}}	Colon missing.	Python
x == '41'	x === 41	Use strict equality.	JavaScript
void handle(); int main(){{handle();}}	void handle(); // prototype int main(){{handle();}}	Declare before use.	C++
class Order {{ int z; }};	class Order {{ public: int z; }};	Make public.	C++
System.out.println('value')	System.out.println('value');	Add semicolon.	Java
function render(): void {{ return 28; }}	function render(): number {{ return 28; }}	Return type mismatch.	TypeScript
name: test age: 84	name: test age: 84	Correct.	YAML
foo	foo()	Add parentheses.	Kotlin
<br></br>	<br>	Self-closing.	HTML
function render() {{ return {{key:'test'}} }}	function render() {{ return {{key:'test'}}; }}	Return object on same line.	JavaScript
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
let a = 'info'	let a = "info"	Double quotes.	Swift
def compute(): print('data')	def compute(): print('data')	Indent function body.	Python
var x = 95;	var x = 95;	Correct.	Dart
{ "name": "info" }	{ "name": "info" }	Correct.	JSON
cin >> y cout << y;	cin >> y; cout << y;	Add semicolon.	C++
list(10)	if length(list) >= 10, list(10), end	Check length.	MATLAB
def compute puts 'world' end	def compute puts 'world' end	Correct.	Ruby
for (result in arr)	for (result of arr)	for...in iterates keys.	JavaScript
<a href='https://test.org' target='_blank'>	<a href='https://test.org' target='_blank' rel='noopener'>	Add rel for security.	HTML
<p>info <b>world</p></b>	<p>info <b>world</b></p>	Nest properly.	HTML
z > 56 & y < 17	z > 56 and y < 17	Use 'and' not '&'.	Python
if (c = 76) {{}}	if (c == 76) {{}}	Use ==.	Kotlin
if [ $data = 8 ]; then	if [ "$data" = 8 ]; then	Quote variable.	Shell
if (bar = 21)	if (bar == 21)	Use ==.	C++
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
arr[6]	if (arr.indices.contains(6)) arr[6]	Check index.	Kotlin
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
object Person {{ def main(args: Array[String]) = println("value") }}	object Person {{ def main(args: Array[String]): Unit = println("value") }}	Add return type Unit.	Scala
'info' + 38	'info' + str(38)	Can't add int to string.	Python
[x*x for x in data if x > 60]	[x*x for x in data if x > 60]	Correct list comprehension.	Python
void main() {{ print('message') }}	void main() {{ print('message'); }}	Add semicolon.	Dart
$items[15] = 5;	if (isset($items[15])) $items[15] = 5;	Check existence.	PHP
echo result data	echo 'result data'	Quote to prevent splitting.	Shell
if (temp = 87) {}	if (temp == 87) {}	Use ==.	Dart
json.sqrt(19)	import json json.sqrt(19)	Import module first.	Python
function process(y) print(y) end	function process(y) print(y) end	Correct.	Lua
if result > 7 print('value')	if result > 7: print('value')	Colon missing after if.	Python
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
INSERT INTO users VALUES ('info',18)	INSERT INTO users (age, role) VALUES ('info',18);	Specify columns.	SQL
my @arr = (58,90,97);	my @arr = (58,90,97);	Correct.	Perl
print 'info'	print('info')	print needs parentheses.	Python
if (a = 4)	if (a == 4)	Use ==.	Scala
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
var temp int = 'value'	var temp string = 'value'	Type mismatch.	Go
$list[9]	if ($list.Count -gt 9) {{ $list[9] }}	Check bounds.	PowerShell
function compute() {{ echo 'message'; }}	function compute() {{ echo 'message'; }}	Correct.	PHP
value: test age: world,	value: test age: world	Remove comma.	YAML
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
console.log('data'	console.log('data')	Close parenthesis.	JavaScript
val temp = 68; temp = 75	var temp = 68; temp = 75	Use var for reassignment.	Scala
cin >> y;	int y; cin >> y;	Declare variable.	C++
jwt.sign({{id:12}}, 'key');	jwt.sign({{id:12}}, 'key', {{expiresIn:'30m'}});	Add expiration.	Node.js
h1 {{ font-size:9px color:green; }}	h1 {{ font-size:9px; color:green; }}	Add semicolon.	CSS
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
if (b = 29) {{}}	if (b == 29) {{}}	Use ==.	Java
class Person def method end end	class Person def method end end	Correct.	Ruby
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
p {{ color: #333 }}	p {{ color: #333; }}	Add semicolon.	CSS
<img src='value.jpg'>	<img src='value.jpg' alt='desc'>	Add alt text.	HTML
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
<hr></hr>	<hr>	Self-closing.	HTML
x := 86	x := 86	Correct.	Go
if foo > 63 puts 'hello'	if foo > 63 puts 'hello' end	Add 'end'.	Ruby
function compute(count:string){{return count;}} compute(1);	function compute(count:string){{return count;}} compute('world');	Pass correct type.	TypeScript
yield temp	yield temp	Correct yield.	Python
<div color=green>	<div style='color:green;'>	Use style attribute.	CSS
switch(index){{ case 59: break; }}	switch(index){{ case 59: break; default: break; }}	Add default case.	Java
<?php // code ?>	<?php // code ?>	Correct.	PHP
local count = 6	local count = 6	Correct.	Lua
// comment	/* comment */	Use /* */.	CSS
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin

div {{ color=green; }}

div {{ color: green; }}

Use colon.

CSS

let num = 29; num += 1;

let mut num = 29; num += 1;

Need mut to modify.

Rust

<center>value</center>

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

Use CSS.

HTML

let v=vec![46,47,69]; let first=&v[0]; v.push(26);

let mut v=vec![46,47,69]; let first=v[0]; v.push(26);

Copy instead of reference.

Rust

for i=1,77 do print(i) end

Correct.

Lua

count = 67

count=67

No spaces.

Shell

List(72,43,97)

Correct.

Scala

print 'hello'

print('hello')

Parentheses for function call.

Lua

if data = 10

if data == 10

Use ==.

MATLAB

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

'100' + 59

100 + 59

Avoid string coercion.

JavaScript

fmt.Println 'value'

fmt.Println('value')

Missing parentheses.

Go

let index = 12; let index = 57;

let index = 12; index = 57;

Duplicate declaration.

JavaScript

let s1 = String::from("data"); let text2 = s1; println!("{{}}", s1);

let s1 = String::from("data"); let text2 = s1.clone(); println!("{{}}", s1);

Clone to avoid move.

Rust

list: - item1 - item2

Correct.

YAML

let z: Int = 'result'

let z: String = 'result'

Fix type.

Swift

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

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

Initialize variable.

Java

UPDATE items SET age='data' WHERE status=86

UPDATE items SET age='data' WHERE status=86;

Add semicolon.

SQL

String y = 'result';

String y = "result";

Double quotes.

Java

'result' + 78

'result' + 78.to_s

Convert int.

Ruby

package main func main() {{}}

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

Import needed.

Go

const count;

const count = 18;

Initialize const.

JavaScript

val foo: Int = 'info'

val foo: String = 'info'

Fix type.

Kotlin

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(94);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(94, () => console.log('listening'));

Add callback.

Node.js

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

[52, 18, 88

[52, 18, 88]

Close bracket.

Ruby

let x: number = 'output';

let x: string = 'output';

Fix type.

TypeScript

JOIN profiles ON orders.id = profiles.id

Correct.

SQL

Colon missing.

Python

x == '41'

x === 41

Use strict equality.

JavaScript

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

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

Declare before use.

C++

class Order {{ int z; }};

class Order {{ public: int z; }};

Make public.

C++

System.out.println('value')

System.out.println('value');

Add semicolon.

Java

function render(): void {{ return 28; }}

function render(): number {{ return 28; }}

Return type mismatch.

TypeScript

name: test age: 84

Correct.

YAML

foo

foo()

Add parentheses.

Kotlin

<br>

Self-closing.

HTML

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

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

Return object on same line.

JavaScript

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

Correct.

Java

let a = 'info'

let a = "info"

Double quotes.

Swift

def compute(): print('data')

Indent function body.

Python

var x = 95;

Correct.

Dart

{ "name": "info" }

Correct.

JSON

cin >> y cout << y;

cin >> y; cout << y;

Add semicolon.

C++

list(10)

if length(list) >= 10, list(10), end

Check length.

MATLAB

def compute puts 'world' end

Correct.

Ruby

for (result in arr)

for (result of arr)

for...in iterates keys.

JavaScript

Add rel for security.

HTML

<p>info <b>world</p></b>

<p>info <b>world</b></p>

Nest properly.

HTML

z > 56 & y < 17

z > 56 and y < 17

Use 'and' not '&'.

Python

if (c = 76) {{}}

if (c == 76) {{}}

Use ==.

Kotlin

if [ $data = 8 ]; then

if [ "$data" = 8 ]; then

Quote variable.

Shell

if (bar = 21)

if (bar == 21)

Use ==.

C++

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

Correct.

CSS

arr[6]

if (arr.indices.contains(6)) arr[6]

Check index.

Kotlin

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

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

Type not in union.

TypeScript

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

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

Add return type Unit.

Scala

'info' + 38

'info' + str(38)

Can't add int to string.

Python

[x*x for x in data if x > 60]

Correct list comprehension.

Python

void main() {{ print('message') }}

void main() {{ print('message'); }}

Add semicolon.

Dart

$items[15] = 5;

if (isset($items[15])) $items[15] = 5;

Check existence.

PHP

echo result data

echo 'result data'

Quote to prevent splitting.

Shell

if (temp = 87) {}

if (temp == 87) {}

Use ==.

Dart

json.sqrt(19)

import json json.sqrt(19)

Import module first.

Python

function process(y) print(y) end

Correct.

Lua

if result > 7 print('value')

if result > 7: print('value')

Colon missing after if.

Python

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

INSERT INTO users VALUES ('info',18)

INSERT INTO users (age, role) VALUES ('info',18);

Specify columns.

SQL

my @arr = (58,90,97);

Correct.

Perl

print 'info'

print('info')

print needs parentheses.

Python

if (a = 4)

if (a == 4)

Use ==.

Scala

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

var temp int = 'value'

var temp string = 'value'

Type mismatch.

Go

$list[9]

if ($list.Count -gt 9) {{ $list[9] }}

Check bounds.

PowerShell

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

Correct.

PHP

value: test age: world,

value: test age: world

Remove comma.

YAML

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

console.log('data'

console.log('data')

Close parenthesis.

JavaScript

val temp = 68; temp = 75

var temp = 68; temp = 75

Use var for reassignment.

Scala

cin >> y;

int y; cin >> y;

Declare variable.

C++

jwt.sign({{id:12}}, 'key');

jwt.sign({{id:12}}, 'key', {{expiresIn:'30m'}});

Add expiration.

Node.js

h1 {{ font-size:9px color:green; }}

h1 {{ font-size:9px; color:green; }}

Add semicolon.

CSS

int main() {{ return 0; }}

Correct.

C++

if (b = 29) {{}}

if (b == 29) {{}}

Use ==.

Java

class Person def method end end

Correct.

Ruby

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

Correct.

R

p {{ color: #333 }}

p {{ color: #333; }}

Add semicolon.

CSS

Add alt text.

HTML

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

<hr>

Self-closing.

HTML

x := 86

Correct.

Go

if foo > 63 puts 'hello'

if foo > 63 puts 'hello' end

Add 'end'.

Ruby

function compute(count:string){{return count;}} compute(1);

function compute(count:string){{return count;}} compute('world');

Pass correct type.

TypeScript

yield temp

Correct yield.

Python

Use style attribute.

CSS

switch(index){{ case 59: break; }}

switch(index){{ case 59: break; default: break; }}

Add default case.

Java

<?php // code ?>

Correct.

PHP

local count = 6

Correct.

Lua

// comment

/* comment */

Use /* */.

CSS

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin