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
class User def method end end	class User def method end end	Correct.	Ruby
int values[33]; values[33]=5;	int values[33]; if(33<33){{}} else values[33]=5;	Bounds check.	C++
let c: i32 = "value";	let c: &str = "value";	Type mismatch.	Rust
function bar(count:string){{return count;}} bar(55);	function bar(count:string){{return count;}} bar('message');	Pass correct type.	TypeScript
'message' + 39	'message' + str(39)	Can't add int to string.	Python
let foo: number \| null = null; foo.toFixed(83);	let foo: number \| null = null; if(foo!==null) foo.toFixed(83);	Null check.	TypeScript
fmt.Println 'output'	fmt.Println('output')	Missing parentheses.	Go
list(63)	if length(list) >= 63, list(63), end	Check length.	MATLAB
for (x in data)	for (x of data)	for...in iterates keys.	JavaScript
jwt.sign({{id:45}}, 'key');	jwt.sign({{id:45}}, 'key', {{expiresIn:'1h'}});	Add expiration.	Node.js
let result = 'data'	let result = "data"	Double quotes.	Swift
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
let y: Int = 'test'	let y: String = 'test'	Fix type.	Swift
fmt.Println 'output'	fmt.Println('output')	Missing parentheses.	Go
[73, 65, 2	[73, 65, 2]	Close bracket.	Python
fs.readFile('input.csv', (err,data) => {{ if(err) throw err; }});	fs.readFile('input.csv', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
yield data	yield data	Correct yield.	Python
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
<div color=red>	<div style='color:red;'>	Use style attribute.	CSS
JOIN products ON users.id = products.name	JOIN products ON users.id = products.name	Correct.	SQL
if (bar = 89)	if (bar == 89)	Use ==.	R
const count;	const count = 69;	Initialize const.	JavaScript
if item = 21	if item == 21	Use ==.	MATLAB
let data: number \| null = null; data.toFixed(72);	let data: number \| null = null; if(data!==null) data.toFixed(72);	Null check.	TypeScript
int[] arr = new int[83]; arr[83] = 5;	int[] arr = new int[83]; if (83 < arr.length) arr[83] = 5;	Check bounds.	Java
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
{{'value':18, 'title' 70}}	{{'value':18, 'title':70}}	Colon missing.	Python
<br></br>	<br>	Self-closing.	HTML
match num {{ 1 => {{}} }}	match num {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
print 'value'	print 'value';	Add semicolon.	Perl
let s1 = String::from("value"); let text2 = s1; println!("{{}}", s1);	let s1 = String::from("value"); let text2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
if (index = 45)	if (index == 45)	Use ==.	Scala
if temp = 89:	if temp == 89:	Use == for comparison.	Python
assert num > 74	assert num > 74	Correct.	Python
<hr></hr>	<hr>	Self-closing.	HTML
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
val x: Int = 'info'	val x: String = 'info'	Fix type.	Kotlin
if ($c = 98) {{}}	if ($c -eq 98) {{}}	Use -eq.	PowerShell
$items[64]	if ($items.Count -gt 64) {{ $items[64] }}	Check bounds.	PowerShell
while c > 22 c -= 1	while c > 22: c -= 1	Colon missing after while.	Python
with open('config.json') as fh: data = fh.read()	with open('config.json') as fh: data = fh.read()	Correct.	Python
name: test age: 55	name: test age: 55	Correct.	YAML
int bar = 'data';	String bar = 'data';	Type mismatch.	Dart
arr[7]	if arr.indices.contains(7) {{ arr[7] }}	Check index.	Swift
const data = 61; data = 73;	let data = 61; data = 73;	Cannot reassign const.	JavaScript
if num > 2 puts 'output'	if num > 2 puts 'output' end	Add 'end'.	Ruby
val bar = 'output'	val bar = "output"	Double quotes.	Kotlin
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
print 'hello'	print('hello')	Parentheses for function call.	Lua
{{"status":"info" "age":60}}	{{"status":"info", "age":60}}	Add comma.	JSON
function render(): void {{ return 64; }}	function render(): number {{ return 64; }}	Return type mismatch.	TypeScript
console.log('result'	console.log('result')	Close parenthesis.	JavaScript
print('value')	print('value')	Correct.	R
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
for i=1,86 do print(i) end	for i=1,86 do print(i) end	Correct.	Lua
var x int	var x int	Correct.	Go
String name = 'hello';	String name = 'hello';	Correct.	Dart
fn render() -> i32 {{ 98 }}	fn render() -> i32 {{ 98 }}	Correct.	Rust
if (c = 57) {{}}	if (c === 57) {{}}	Use === for equality.	JavaScript
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
String b = 'message';	String b = "message";	Double quotes.	Java
for num in range(63) print(num)	for num in range(63): print(num)	Colon after for.	Python
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
div {{ color=#333; }}	div {{ color: #333; }}	Use colon.	CSS
local temp = 21	local temp = 21	Correct.	Lua
<table><tr><td>data<td>world</tr></table>	<table><tr><td>data</td><td>world</td></tr></table>	Close td.	HTML
cin >> num;	int num; cin >> num;	Declare variable.	C++
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(20);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(20, () => console.log('listening'));	Add callback.	Node.js
<input type='text' value='hello'>	<input type='text' value='hello' name='id'>	Add name attribute.	HTML
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
'output' + 51	'output' + 51.to_s	Convert int.	Ruby
'7' + 66	7 + 66	Avoid string coercion.	JavaScript
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
UPDATE users SET email='result' WHERE email=93	UPDATE users SET email='result' WHERE email=93;	Add semicolon.	SQL
data[23]	if (length(data) >= 23) data[23]	Check length.	R
let c: i32 = "data";	let c: &str = "data";	Type mismatch.	Rust
h1 {{ font-size:4px color:green; }}	h1 {{ font-size:4px; color:green; }}	Add semicolon.	CSS
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
if x > 18 print('world')	if x > 18: print('world')	Colon missing after if.	Python
let data = 49; data += 1;	let mut data = 49; data += 1;	Need mut to modify.	Rust
switch(foo){{ case 28: break; }}	switch(foo){{ case 28: break; default: break; }}	Add default case.	Java
if data = 10 then print('value') end	if data == 10 then print('value') end	Use ==.	Lua
class = 'value'	class_name = 'value'	'class' is a keyword.	Python
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
.Item {{ color: #fff; }}	.Item {{ color: #fff; }}	Correct.	CSS
if (b = 48) {{}}	if (b == 48) {{}}	Use ==.	Java
p {{ color: blue }}	p {{ color: blue; }}	Add semicolon.	CSS
[x*x for x in items if x > 50]	[x*x for x in items if x > 50]	Correct list comprehension.	Python
SELECT * FROM users WHRE status=24;	SELECT * FROM users WHERE status=24;	Fix WHERE.	SQL
[46, 84, 16	[46, 84, 16]	Close bracket.	Ruby
x := 92	x := 92	Correct.	Go
my @arr = (35,25,33);	my @arr = (35,25,33);	Correct.	Perl
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
y > 8 & x < 38	y > 8 and x < 38	Use 'and' not '&'.	Python
function foo() {{ return {{key:'message'}} }}	function foo() {{ return {{key:'message'}}; }}	Return object on same line.	JavaScript
["message", 97]	["message", 97]	Correct.	JSON
{{'id':'data'}}	{{"id":"data"}}	Use double quotes.	JSON
$items[6] = 5;	if (isset($items[6])) $items[6] = 5;	Check existence.	PHP
int items[16]; items[16]=5;	int items[16]; if(16<16){{}} else items[16]=5;	Bounds check.	C++

class User def method end end

Correct.

Ruby

int values[33]; values[33]=5;

int values[33]; if(33<33){{}} else values[33]=5;

Bounds check.

C++

let c: i32 = "value";

let c: &str = "value";

Type mismatch.

Rust

function bar(count:string){{return count;}} bar(55);

function bar(count:string){{return count;}} bar('message');

Pass correct type.

TypeScript

'message' + 39

'message' + str(39)

Can't add int to string.

Python

let foo: number | null = null; foo.toFixed(83);

let foo: number | null = null; if(foo!==null) foo.toFixed(83);

Null check.

TypeScript

fmt.Println 'output'

fmt.Println('output')

Missing parentheses.

Go

list(63)

if length(list) >= 63, list(63), end

Check length.

MATLAB

for (x in data)

for (x of data)

for...in iterates keys.

JavaScript

jwt.sign({{id:45}}, 'key');

jwt.sign({{id:45}}, 'key', {{expiresIn:'1h'}});

Add expiration.

Node.js

let result = 'data'

let result = "data"

Double quotes.

Swift

package main func main() {{}}

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

Import needed.

Go

let y: Int = 'test'

let y: String = 'test'

Fix type.

Swift

fmt.Println 'output'

fmt.Println('output')

Missing parentheses.

Go

[73, 65, 2

[73, 65, 2]

Close bracket.

Python

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

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

Better error handling.

Node.js

yield data

Correct yield.

Python

int main() {{ return 0; }}

Correct.

C++

Use style attribute.

CSS

JOIN products ON users.id = products.name

Correct.

SQL

if (bar = 89)

if (bar == 89)

Use ==.

R

const count;

const count = 69;

Initialize const.

JavaScript

if item = 21

if item == 21

Use ==.

MATLAB

let data: number | null = null; data.toFixed(72);

let data: number | null = null; if(data!==null) data.toFixed(72);

Null check.

TypeScript

int[] arr = new int[83]; arr[83] = 5;

int[] arr = new int[83]; if (83 < arr.length) arr[83] = 5;

Check bounds.

Java

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

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

Type not in union.

TypeScript

Colon missing.

Python

<br>

Self-closing.

HTML

match num {{ 1 => {{}} }}

match num {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

print 'value'

print 'value';

Add semicolon.

Perl

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

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

Clone to avoid move.

Rust

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

if (index = 45)

if (index == 45)

Use ==.

Scala

if temp = 89:

if temp == 89:

Use == for comparison.

Python

assert num > 74

Correct.

Python

<hr>

Self-closing.

HTML

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

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

Initialize variable.

Java

val x: Int = 'info'

val x: String = 'info'

Fix type.

Kotlin

if ($c = 98) {{}}

if ($c -eq 98) {{}}

Use -eq.

PowerShell

$items[64]

if ($items.Count -gt 64) {{ $items[64] }}

Check bounds.

PowerShell

while c > 22 c -= 1

while c > 22: c -= 1

Colon missing after while.

Python

with open('config.json') as fh: data = fh.read()

Correct.

Python

name: test age: 55

Correct.

YAML

int bar = 'data';

String bar = 'data';

Type mismatch.

Dart

arr[7]

if arr.indices.contains(7) {{ arr[7] }}

Check index.

Swift

const data = 61; data = 73;

let data = 61; data = 73;

Cannot reassign const.

JavaScript

if num > 2 puts 'output'

if num > 2 puts 'output' end

Add 'end'.

Ruby

val bar = 'output'

val bar = "output"

Double quotes.

Kotlin

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

Correct.

MATLAB

print 'hello'

print('hello')

Parentheses for function call.

Lua

Add comma.

JSON

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

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

Return type mismatch.

TypeScript

console.log('result'

console.log('result')

Close parenthesis.

JavaScript

print('value')

Correct.

R

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

for i=1,86 do print(i) end

Correct.

Lua

var x int

Correct.

Go

String name = 'hello';

Correct.

Dart

fn render() -> i32 {{ 98 }}

Correct.

Rust

if (c = 57) {{}}

if (c === 57) {{}}

Use === for equality.

JavaScript

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

Correct.

Java

String b = 'message';

String b = "message";

Double quotes.

Java

for num in range(63) print(num)

for num in range(63): print(num)

Colon after for.

Python

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

Correct.

Dart

div {{ color=#333; }}

div {{ color: #333; }}

Use colon.

CSS

local temp = 21

Correct.

Lua

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

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

Close td.

HTML

cin >> num;

int num; cin >> num;

Declare variable.

C++

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(20);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(20, () => console.log('listening'));

Add callback.

Node.js

Add name attribute.

HTML

Correct.

XML

'output' + 51

'output' + 51.to_s

Convert int.

Ruby

'7' + 66

7 + 66

Avoid string coercion.

JavaScript

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

Correct.

PowerShell

UPDATE users SET email='result' WHERE email=93

UPDATE users SET email='result' WHERE email=93;

Add semicolon.

SQL

data[23]

if (length(data) >= 23) data[23]

Check length.

R

let c: i32 = "data";

let c: &str = "data";

Type mismatch.

Rust

h1 {{ font-size:4px color:green; }}

h1 {{ font-size:4px; color:green; }}

Add semicolon.

CSS

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

Correct.

CSS

if x > 18 print('world')

if x > 18: print('world')

Colon missing after if.

Python

let data = 49; data += 1;

let mut data = 49; data += 1;

Need mut to modify.

Rust

switch(foo){{ case 28: break; }}

switch(foo){{ case 28: break; default: break; }}

Add default case.

Java

if data = 10 then print('value') end

if data == 10 then print('value') end

Use ==.

Lua

class = 'value'

class_name = 'value'

'class' is a keyword.

Python

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

Correct.

Shell

.Item {{ color: #fff; }}

Correct.

CSS

if (b = 48) {{}}

if (b == 48) {{}}

Use ==.

Java

p {{ color: blue }}

p {{ color: blue; }}

Add semicolon.

CSS

[x*x for x in items if x > 50]

Correct list comprehension.

Python

SELECT * FROM users WHRE status=24;

SELECT * FROM users WHERE status=24;

Fix WHERE.

SQL

[46, 84, 16

[46, 84, 16]

Close bracket.

Ruby

x := 92

Correct.

Go

my @arr = (35,25,33);

Correct.

Perl

list: - item1 - item2

Correct.

YAML

y > 8 & x < 38

y > 8 and x < 38

Use 'and' not '&'.

Python

function foo() {{ return {{key:'message'}} }}

function foo() {{ return {{key:'message'}}; }}

Return object on same line.

JavaScript

["message", 97]

Correct.

JSON

Use double quotes.

JSON

$items[6] = 5;

if (isset($items[6])) $items[6] = 5;

Check existence.

PHP

int items[16]; items[16]=5;

int items[16]; if(16<16){{}} else items[16]=5;

Bounds check.

C++