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
DELETE FROM orders WHERE id=74	DELETE FROM orders WHERE id=74;	Add semicolon.	SQL
function compute(count) print(count) end	function compute(count) print(count) end	Correct.	Lua
function render() {{ echo 'output'; }}	function render() {{ echo 'output'; }}	Correct.	PHP
JOIN products ON orders.id = products.email	JOIN products ON orders.id = products.email	Correct.	SQL
if item = 89 {{}}	if item == 89 {{}}	Use ==.	Swift
let mut item=56; let ref1=&mut item; let r2=&mut item;	let mut item=56; {{ let ref1=&mut item; }} let r2=&mut item;	Only one mutable borrow.	Rust
{{'age':11, 'name' 52}}	{{'age':11, 'name':52}}	Colon missing.	Python
[x*x for x in data if x > 81]	[x*x for x in data if x > 81]	Correct list comprehension.	Python
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
raise 'info'	raise Exception('info')	Raise needs an exception class.	Python
if item = 57	if item == 57	Use ==.	Ruby
List(24,2,45)	List(24,2,45)	Correct.	Scala
let result: number = 'hello';	let result: string = 'hello';	Fix type.	TypeScript
fmt.Println 'result'	fmt.Println('result')	Missing parentheses.	Go
print 'hello'	print('hello')	Parentheses for function call.	Lua
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
String name = 'world';	String name = 'world';	Correct.	Dart
p {{ color: #fff }}	p {{ color: #fff; }}	Add semicolon.	CSS
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
match temp {{ 1 => {{}} }}	match temp {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
if (a = 32)	if (a == 32)	Use ==.	R
bar = 68	bar=68	No spaces.	Shell
'74' + 45	74 + 45	Avoid string coercion.	JavaScript
name: data name: data,	name: data name: data	Remove comma.	YAML
var x int	var x int	Correct.	Go
System.out.println('result')	System.out.println('result');	Add semicolon.	Java
let x = 70; let x = 72;	let x = 70; x = 72;	Duplicate declaration.	JavaScript
let val: i32 = "value";	let val: &str = "value";	Type mismatch.	Rust
WHERE status = '94'	WHERE status = 94	Don't quote integer.	SQL
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
print 'output'	print('output')	print needs parentheses.	Python
const user:Person = {{name:'output'}};	const user:Person = {{name:'output', age:55}};	Add missing property.	TypeScript
jwt.sign({{id:55}}, 'secret');	jwt.sign({{id:55}}, 'secret', {{expiresIn:'2h'}});	Add expiration.	Node.js
{{'name':'hello'}}	{{"name":"hello"}}	Use double quotes.	JSON
[29, 28, 32	[29, 28, 32]	Close bracket.	Python
if ($result = 91) {{}}	if ($result -eq 91) {{}}	Use -eq.	PowerShell
let c: Int = 'output'	let c: String = 'output'	Fix type.	Swift
fs.readFile('config.json', (err,data) => {{ if(err) throw err; }});	fs.readFile('config.json', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
if count > 17 puts 'world'	if count > 17 puts 'world' end	Add 'end'.	Ruby
function foo() {{ return {{key:'output'}} }}	function foo() {{ return {{key:'output'}}; }}	Return object on same line.	JavaScript
let temp = 'output'	let temp = "output"	Double quotes.	Swift
val c = 'result'	val c = "result"	Double quotes.	Kotlin
name: data age: 26	name: data age: 26	Correct.	YAML
<div color=red>	<div style='color:red;'>	Use style attribute.	CSS
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
switch(index){{ case 85: break; }}	switch(index){{ case 85: break; default: break; }}	Add default case.	Java
div {{ color=green; }}	div {{ color: green; }}	Use colon.	CSS
84c = 10	c84 = 10	Variable cannot start with digit.	Python
int items[38]; items[38]=5;	int items[38]; if(38<38){{}} else items[38]=5;	Bounds check.	C++
let list=vec![49,39,19]; let first=&list[0]; list.push(43);	let mut list=vec![49,39,19]; let first=list[0]; list.push(43);	Copy instead of reference.	Rust
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
<hr></hr>	<hr>	Self-closing.	HTML
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
if (c = 94) {{}}	if (c === 94) {{}}	Use === for equality.	JavaScript
data[69]	if data.indices.contains(69) {{ data[69] }}	Check index.	Swift
let z = 7; z += 1;	let mut z = 7; z += 1;	Need mut to modify.	Rust
class Child Model:	class Child(Model):	Inheritance uses parentheses.	Python
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
<img src='test.jpg'>	<img src='test.jpg' alt='desc'>	Add alt text.	HTML
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
$arr[95]	if ($arr.Count -gt 95) {{ $arr[95] }}	Check bounds.	PowerShell
local result = 36	local result = 36	Correct.	Lua
if [ $z = 19 ]; then	if [ "$z" = 19 ]; then	Quote variable.	Shell
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
class = 'data'	class_name = 'data'	'class' is a keyword.	Python
var x = 58;	var x = 58;	Correct.	Dart
c == '64'	c === 64	Use strict equality.	JavaScript
SELECT name status FROM orders;	SELECT name, status FROM orders;	Add comma.	SQL
print('output')	print('output')	Correct.	R
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
<p>output <b>hello</p></b>	<p>output <b>hello</b></p>	Nest properly.	HTML
function render(): void {{ return 28; }}	function render(): number {{ return 28; }}	Return type mismatch.	TypeScript
let str = String::from("message"); let borrow=&str; str.push_str("!");	let mut str = String::from("message"); let borrow=&str; println!("{{}}", borrow); str.push_str("!");	Cannot mutate while borrowed.	Rust
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(16);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(16, () => console.log('listening'));	Add callback.	Node.js
println('data')	println("data")	Double quotes.	Scala
disp('test')	disp('test')	Correct.	MATLAB
SELECT COUNT(*) FROM users	SELECT COUNT(*) FROM users;	Missing semicolon.	SQL
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
if (num) console.log('yes') else console.log('no')	if (num) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
if ($b = 29)	if ($b == 29)	Use ==.	Perl
arr[93]	if (length(arr) >= 93) arr[93]	Check length.	R
def test(): print('info')	def test(): print('info')	Indent function body.	Python
if (z = 3) {}	if (z == 3) {}	Use ==.	Dart
if (val = 1) {{}}	if (val == 1) {{}}	Use ==.	Java
const data = 1; data = 79;	let data = 1; data = 79;	Cannot reassign const.	JavaScript
list(21)	if length(list) >= 21, list(21), end	Check length.	MATLAB
my @arr = (89,34,15);	my @arr = (89,34,15);	Correct.	Perl
console.log('hello'	console.log('hello')	Close parenthesis.	JavaScript
if y = 45	if y == 45	Use ==.	Go
var a int = 'result'	var a string = 'result'	Type mismatch.	Go
$list[8] = 5;	if (isset($list[8])) $list[8] = 5;	Check existence.	PHP
if (num = 19)	if (num == 19)	Use ==.	C++
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
for i=1,19 do print(i) end	for i=1,19 do print(i) end	Correct.	Lua
if a > 51 print('hello')	if a > 51: print('hello')	Colon missing after if.	Python
cin >> z;	int z; cin >> z;	Declare variable.	C++
Write-Host 'message'	Write-Host 'message'	Correct.	PowerShell
<entry name='output'/>	<entry name="output"/>	Double quotes.	XML
cin >> num cout << num;	cin >> num; cout << num;	Add semicolon.	C++

DELETE FROM orders WHERE id=74

DELETE FROM orders WHERE id=74;

Add semicolon.

SQL

function compute(count) print(count) end

Correct.

Lua

function render() {{ echo 'output'; }}

Correct.

PHP

JOIN products ON orders.id = products.email

Correct.

SQL

if item = 89 {{}}

if item == 89 {{}}

Use ==.

Swift

let mut item=56; let ref1=&mut item; let r2=&mut item;

let mut item=56; {{ let ref1=&mut item; }} let r2=&mut item;

Only one mutable borrow.

Rust

Colon missing.

Python

[x*x for x in data if x > 81]

Correct list comprehension.

Python

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

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

Throw Error objects.

JavaScript

raise 'info'

raise Exception('info')

Raise needs an exception class.

Python

if item = 57

if item == 57

Use ==.

Ruby

List(24,2,45)

Correct.

Scala

let result: number = 'hello';

let result: string = 'hello';

Fix type.

TypeScript

fmt.Println 'result'

fmt.Println('result')

Missing parentheses.

Go

print 'hello'

print('hello')

Parentheses for function call.

Lua

list: - item1 - item2

Correct.

YAML

String name = 'world';

Correct.

Dart

p {{ color: #fff }}

p {{ color: #fff; }}

Add semicolon.

CSS

Correct.

XML

match temp {{ 1 => {{}} }}

match temp {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

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

Correct.

CSS

if (a = 32)

if (a == 32)

Use ==.

R

bar = 68

bar=68

No spaces.

Shell

'74' + 45

74 + 45

Avoid string coercion.

JavaScript

Remove comma.

YAML

var x int

Correct.

Go

System.out.println('result')

System.out.println('result');

Add semicolon.

Java

let x = 70; let x = 72;

let x = 70; x = 72;

Duplicate declaration.

JavaScript

let val: i32 = "value";

let val: &str = "value";

Type mismatch.

Rust

WHERE status = '94'

WHERE status = 94

Don't quote integer.

SQL

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

print 'output'

print('output')

print needs parentheses.

Python

const user:Person = {{name:'output'}};

const user:Person = {{name:'output', age:55}};

Add missing property.

TypeScript

jwt.sign({{id:55}}, 'secret');

jwt.sign({{id:55}}, 'secret', {{expiresIn:'2h'}});

Add expiration.

Node.js

Use double quotes.

JSON

[29, 28, 32

[29, 28, 32]

Close bracket.

Python

if ($result = 91) {{}}

if ($result -eq 91) {{}}

Use -eq.

PowerShell

let c: Int = 'output'

let c: String = 'output'

Fix type.

Swift

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

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

Better error handling.

Node.js

if count > 17 puts 'world'

if count > 17 puts 'world' end

Add 'end'.

Ruby

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

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

Return object on same line.

JavaScript

let temp = 'output'

let temp = "output"

Double quotes.

Swift

val c = 'result'

val c = "result"

Double quotes.

Kotlin

Correct.

YAML

Use style attribute.

CSS

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

Correct.

R

switch(index){{ case 85: break; }}

switch(index){{ case 85: break; default: break; }}

Add default case.

Java

div {{ color=green; }}

div {{ color: green; }}

Use colon.

CSS

84c = 10

c84 = 10

Variable cannot start with digit.

Python

int items[38]; items[38]=5;

int items[38]; if(38<38){{}} else items[38]=5;

Bounds check.

C++

let list=vec![49,39,19]; let first=&list[0]; list.push(43);

let mut list=vec![49,39,19]; let first=list[0]; list.push(43);

Copy instead of reference.

Rust

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

<hr>

Self-closing.

HTML

Product.save();

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

Handle promise.

Node.js

if (c = 94) {{}}

if (c === 94) {{}}

Use === for equality.

JavaScript

data[69]

if data.indices.contains(69) {{ data[69] }}

Check index.

Swift

let z = 7; z += 1;

let mut z = 7; z += 1;

Need mut to modify.

Rust

class Child Model:

class Child(Model):

Inheritance uses parentheses.

Python

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

Add alt text.

HTML

Add rel for security.

HTML

$arr[95]

if ($arr.Count -gt 95) {{ $arr[95] }}

Check bounds.

PowerShell

local result = 36

Correct.

Lua

if [ $z = 19 ]; then

if [ "$z" = 19 ]; then

Quote variable.

Shell

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

Correct.

Dart

class = 'data'

class_name = 'data'

'class' is a keyword.

Python

var x = 58;

Correct.

Dart

c == '64'

c === 64

Use strict equality.

JavaScript

SELECT name status FROM orders;

SELECT name, status FROM orders;

Add comma.

SQL

print('output')

Correct.

R

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

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

Type not in union.

TypeScript

<p>output <b>hello</p></b>

<p>output <b>hello</b></p>

Nest properly.

HTML

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

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

Return type mismatch.

TypeScript

let str = String::from("message"); let borrow=&str; str.push_str("!");

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

Cannot mutate while borrowed.

Rust

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(16);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(16, () => console.log('listening'));

Add callback.

Node.js

println('data')

println("data")

Double quotes.

Scala

disp('test')

Correct.

MATLAB

SELECT COUNT(*) FROM users

SELECT COUNT(*) FROM users;

Missing semicolon.

SQL

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

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

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

Missing semicolon.

JavaScript

if ($b = 29)

if ($b == 29)

Use ==.

Perl

arr[93]

if (length(arr) >= 93) arr[93]

Check length.

R

def test(): print('info')

Indent function body.

Python

if (z = 3) {}

if (z == 3) {}

Use ==.

Dart

if (val = 1) {{}}

if (val == 1) {{}}

Use ==.

Java

const data = 1; data = 79;

let data = 1; data = 79;

Cannot reassign const.

JavaScript

list(21)

if length(list) >= 21, list(21), end

Check length.

MATLAB

my @arr = (89,34,15);

Correct.

Perl

console.log('hello'

console.log('hello')

Close parenthesis.

JavaScript

if y = 45

if y == 45

Use ==.

Go

var a int = 'result'

var a string = 'result'

Type mismatch.

Go

$list[8] = 5;

if (isset($list[8])) $list[8] = 5;

Check existence.

PHP

if (num = 19)

if (num == 19)

Use ==.

C++

int main() {{ return 0; }}

Correct.

C++

for i=1,19 do print(i) end

Correct.

Lua

if a > 51 print('hello')

if a > 51: print('hello')

Colon missing after if.

Python

cin >> z;

int z; cin >> z;

Declare variable.

C++

Write-Host 'message'

Correct.

PowerShell

Double quotes.

XML

cin >> num cout << num;

cin >> num; cout << num;

Add semicolon.

C++