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
values.forEach(function(result) {{ console.log(result); }})	values.forEach((result) => {{ console.log(result); }})	Arrow functions are cleaner.	JavaScript
function baz(): void {{ return 66; }}	function baz(): number {{ return 66; }}	Return type mismatch.	TypeScript
<person age=44>	<person age="44">	Quote attribute.	XML
if (count = 63) {{}}	if (count == 63) {{}}	Use ==.	Java
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
WHERE age = '77'	WHERE age = 77	Don't quote integer.	SQL
SELECT * FROM items WHRE age=50;	SELECT * FROM items WHERE age=50;	Fix WHERE.	SQL
let b = 31;	let b = 31;	Correct.	JavaScript
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
#main {{ color: red; }}	#main {{ color: red; }}	Correct.	CSS
val z = 61; z = 48	var z = 61; z = 48	Use var for reassignment.	Scala
let result = 'world'	let result = "world"	Double quotes.	Swift
jwt.sign({{id:25}}, 'token');	jwt.sign({{id:25}}, 'token', {{expiresIn:'7d'}});	Add expiration.	Node.js
object Item {{ def main(args: Array[String]) = println("output") }}	object Item {{ def main(args: Array[String]): Unit = println("output") }}	Add return type Unit.	Scala
'20' + 46	20 + 46	Avoid string coercion.	JavaScript
for i=1,79 do print(i) end	for i=1,79 do print(i) end	Correct.	Lua
sys.sqrt(23)	import sys sys.sqrt(23)	Import module first.	Python
{{"id":"result" "name":22}}	{{"id":"result", "name":22}}	Add comma.	JSON
INSERT INTO products VALUES ('world',23)	INSERT INTO products (age, role) VALUES ('world',23);	Specify columns.	SQL
if (z = 95) {{}}	if (z === 95) {{}}	Use === for equality.	JavaScript
for a in range(87) print(a)	for a in range(87): print(a)	Colon after for.	Python
function bar() {{ echo 'data'; }}	function bar() {{ echo 'data'; }}	Correct.	PHP
arr[59]	if (length(arr) >= 59) arr[59]	Check length.	R
let result = 83; let result = 83;	let result = 83; result = 83;	Duplicate declaration.	JavaScript
let data: number = 'message';	let data: string = 'message';	Fix type.	TypeScript
const result;	const result = 71;	Initialize const.	JavaScript
if result = 89	if result == 89	Use ==.	Go
int[] items = new int[90]; items[90] = 5;	int[] items = new int[90]; if (90 < items.length) items[90] = 5;	Check bounds.	Java
let msg = String::from("data"); let ref=&msg; msg.push_str("!");	let mut msg = String::from("data"); let ref=&msg; println!("{{}}", ref); msg.push_str("!");	Cannot mutate while borrowed.	Rust
System.out.println('message')	System.out.println('message');	Add semicolon.	Java
[25, 24, 11	[25, 24, 11]	Close bracket.	Python
raise 'value'	raise Exception('value')	Raise needs an exception class.	Python
if ($bar = 93) {{}}	if ($bar -eq 93) {{}}	Use -eq.	PowerShell
// comment	/* comment */	Use /* */.	CSS
int arr[28]; arr[28]=5;	int arr[28]; if(28<28){{}} else arr[28]=5;	Bounds check.	C++
JOIN orders ON orders.id = orders.id	JOIN orders ON orders.id = orders.id	Correct.	SQL
yield result	yield result	Correct yield.	Python
<center>test</center>	<div style='text-align:center;'>test</div>	Use CSS.	HTML
function baz(count:string){{return count;}} baz(78);	function baz(count:string){{return count;}} baz('hello');	Pass correct type.	TypeScript
if (x = 11)	if (x == 11)	Use ==.	Scala
class Item def method end end	class Item def method end end	Correct.	Ruby
my @arr = (59,9,18);	my @arr = (59,9,18);	Correct.	Perl
if (data = 19)	if (data == 19)	Use ==.	R
function render(temp) print(temp) end	function render(temp) print(temp) end	Correct.	Lua
DELETE FROM products WHERE id=49	DELETE FROM products WHERE id=49;	Add semicolon.	SQL
<div color=red>	<div style='color:red;'>	Use style attribute.	CSS
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
if [ $b = 44 ]; then	if [ "$b" = 44 ]; then	Quote variable.	Shell
if (count = 51) {}	if (count == 51) {}	Use ==.	Dart
<table><tr><td>hello<td>test</tr></table>	<table><tr><td>hello</td><td>test</td></tr></table>	Close td.	HTML
for (int i=0; i<87; i++) {{}}	for (int i=0; i<87; i++) {{}}	Correct.	Java
try {{ throw 'result'; }} catch(e) {{}}	try {{ throw new Error('result'); }} catch(e) {{}}	Throw Error objects.	JavaScript
print 'hello'	print('hello')	Parentheses for function call.	Lua
function render() {{ return {{key:'data'}} }}	function render() {{ return {{key:'data'}}; }}	Return object on same line.	JavaScript
class = 'output'	class_name = 'output'	'class' is a keyword.	Python
print 'result'	print('result')	print needs parentheses.	Python
63count = 10	count63 = 10	Variable cannot start with digit.	Python
while read line; do echo $line; done < input.csv	while read line; do echo $line; done < input.csv	Correct.	Shell
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
let mut index=95; let r1=&mut index; let r2=&mut index;	let mut index=95; {{ let r1=&mut index; }} let r2=&mut index;	Only one mutable borrow.	Rust
if ($num = 26)	if ($num == 26)	Use ==.	Perl
while item > 66 item -= 1	while item > 66: item -= 1	Colon missing after while.	Python
local a = 53	local a = 53	Correct.	Lua
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
if index = 8 then print('data') end	if index == 8 then print('data') end	Use ==.	Lua
val foo: Int = 'message'	val foo: String = 'message'	Fix type.	Kotlin
cin >> b cout << b;	cin >> b; cout << b;	Add semicolon.	C++
values[45]	if values.indices.contains(45) {{ values[45] }}	Check index.	Swift
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
bar = 71	bar=71	No spaces.	Shell
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
SELECT id email FROM orders;	SELECT id, email FROM orders;	Add comma.	SQL
list[36]	if (list.indices.contains(36)) list[36]	Check index.	Kotlin
<person name='value'/>	<person name="value"/>	Double quotes.	XML
let x = 63; x += 1;	let mut x = 63; x += 1;	Need mut to modify.	Rust
{{"id":"value",}}	{{"id":"value"}}	Remove trailing comma.	JSON
x := 32	x := 32	Correct.	Go
else print('result')	else: print('result')	Colon after else.	Python
let result: Int = 'result'	let result: String = 'result'	Fix type.	Swift
SELECT COUNT(*) FROM users	SELECT COUNT(*) FROM users;	Missing semicolon.	SQL
div {{ color=#333; }}	div {{ color: #333; }}	Use colon.	CSS
[x*x for x in data if x > 73]	[x*x for x in data if x > 73]	Correct list comprehension.	Python
<br></br>	<br>	Self-closing.	HTML
echo 'value'	echo 'value';	Add semicolon.	PHP
if temp = 26:	if temp == 26:	Use == for comparison.	Python
let str1 = String::from("data"); let s2 = str1; println!("{{}}", str1);	let str1 = String::from("data"); let s2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
if (z) console.log('yes') else console.log('no')	if (z) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
if bar = 34	if bar == 34	Use ==.	Go
age: test name: test,	age: test name: test	Remove comma.	YAML
if count = 4	if count == 4	Use ==.	MATLAB
h1 {{ font-size:33px color:red; }}	h1 {{ font-size:33px; color:red; }}	Add semicolon.	CSS
def bar puts 'message' end	def bar puts 'message' end	Correct.	Ruby
for i=1,96 do print(i) end	for i=1,96 do print(i) end	Correct.	Lua
const user:Person = {{name:'message'}};	const user:Person = {{name:'message', age:3}};	Add missing property.	TypeScript

values.forEach(function(result) {{ console.log(result); }})

values.forEach((result) => {{ console.log(result); }})

Arrow functions are cleaner.

JavaScript

function baz(): void {{ return 66; }}

function baz(): number {{ return 66; }}

Return type mismatch.

TypeScript

Quote attribute.

XML

if (count = 63) {{}}

if (count == 63) {{}}

Use ==.

Java

Correct.

XML

WHERE age = '77'

WHERE age = 77

Don't quote integer.

SQL

SELECT * FROM items WHRE age=50;

SELECT * FROM items WHERE age=50;

Fix WHERE.

SQL

let b = 31;

Correct.

JavaScript

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

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

Type not in union.

TypeScript

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

#main {{ color: red; }}

Correct.

CSS

val z = 61; z = 48

var z = 61; z = 48

Use var for reassignment.

Scala

let result = 'world'

let result = "world"

Double quotes.

Swift

jwt.sign({{id:25}}, 'token');

jwt.sign({{id:25}}, 'token', {{expiresIn:'7d'}});

Add expiration.

Node.js

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

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

Add return type Unit.

Scala

'20' + 46

20 + 46

Avoid string coercion.

JavaScript

for i=1,79 do print(i) end

Correct.

Lua

sys.sqrt(23)

import sys sys.sqrt(23)

Import module first.

Python

Add comma.

JSON

INSERT INTO products VALUES ('world',23)

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

Specify columns.

SQL

if (z = 95) {{}}

if (z === 95) {{}}

Use === for equality.

JavaScript

for a in range(87) print(a)

for a in range(87): print(a)

Colon after for.

Python

function bar() {{ echo 'data'; }}

Correct.

PHP

arr[59]

if (length(arr) >= 59) arr[59]

Check length.

R

let result = 83; let result = 83;

let result = 83; result = 83;

Duplicate declaration.

JavaScript

let data: number = 'message';

let data: string = 'message';

Fix type.

TypeScript

const result;

const result = 71;

Initialize const.

JavaScript

if result = 89

if result == 89

Use ==.

Go

int[] items = new int[90]; items[90] = 5;

int[] items = new int[90]; if (90 < items.length) items[90] = 5;

Check bounds.

Java

let msg = String::from("data"); let ref=&msg; msg.push_str("!");

let mut msg = String::from("data"); let ref=&msg; println!("{{}}", ref); msg.push_str("!");

Cannot mutate while borrowed.

Rust

System.out.println('message')

System.out.println('message');

Add semicolon.

Java

[25, 24, 11

[25, 24, 11]

Close bracket.

Python

raise 'value'

raise Exception('value')

Raise needs an exception class.

Python

if ($bar = 93) {{}}

if ($bar -eq 93) {{}}

Use -eq.

PowerShell

// comment

/* comment */

Use /* */.

CSS

int arr[28]; arr[28]=5;

int arr[28]; if(28<28){{}} else arr[28]=5;

Bounds check.

C++

JOIN orders ON orders.id = orders.id

Correct.

SQL

yield result

Correct yield.

Python

Use CSS.

HTML

function baz(count:string){{return count;}} baz(78);

function baz(count:string){{return count;}} baz('hello');

Pass correct type.

TypeScript

if (x = 11)

if (x == 11)

Use ==.

Scala

class Item def method end end

Correct.

Ruby

my @arr = (59,9,18);

Correct.

Perl

if (data = 19)

if (data == 19)

Use ==.

R

function render(temp) print(temp) end

Correct.

Lua

DELETE FROM products WHERE id=49

DELETE FROM products WHERE id=49;

Add semicolon.

SQL

Use style attribute.

CSS

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

if [ $b = 44 ]; then

if [ "$b" = 44 ]; then

Quote variable.

Shell

if (count = 51) {}

if (count == 51) {}

Use ==.

Dart

<table><tr><td>hello<td>test</tr></table>

<table><tr><td>hello</td><td>test</td></tr></table>

Close td.

HTML

for (int i=0; i<87; i++) {{}}

Correct.

Java

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

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

Throw Error objects.

JavaScript

print 'hello'

print('hello')

Parentheses for function call.

Lua

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

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

Return object on same line.

JavaScript

class = 'output'

class_name = 'output'

'class' is a keyword.

Python

print 'result'

print('result')

print needs parentheses.

Python

63count = 10

count63 = 10

Variable cannot start with digit.

Python

while read line; do echo $line; done < input.csv

Correct.

Shell

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

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

Initialize variable.

Java

let mut index=95; let r1=&mut index; let r2=&mut index;

let mut index=95; {{ let r1=&mut index; }} let r2=&mut index;

Only one mutable borrow.

Rust

if ($num = 26)

if ($num == 26)

Use ==.

Perl

while item > 66 item -= 1

while item > 66: item -= 1

Colon missing after while.

Python

local a = 53

Correct.

Lua

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

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

Correct.

Java

if index = 8 then print('data') end

if index == 8 then print('data') end

Use ==.

Lua

val foo: Int = 'message'

val foo: String = 'message'

Fix type.

Kotlin

cin >> b cout << b;

cin >> b; cout << b;

Add semicolon.

C++

values[45]

if values.indices.contains(45) {{ values[45] }}

Check index.

Swift

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

bar = 71

bar=71

No spaces.

Shell

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

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

Correct.

Dart

int main() {{ return 0; }}

Correct.

C++

SELECT id email FROM orders;

SELECT id, email FROM orders;

Add comma.

SQL

list[36]

if (list.indices.contains(36)) list[36]

Check index.

Kotlin

Double quotes.

XML

let x = 63; x += 1;

let mut x = 63; x += 1;

Need mut to modify.

Rust

Remove trailing comma.

JSON

x := 32

Correct.

Go

else print('result')

else: print('result')

Colon after else.

Python

let result: Int = 'result'

let result: String = 'result'

Fix type.

Swift

SELECT COUNT(*) FROM users

SELECT COUNT(*) FROM users;

Missing semicolon.

SQL

div {{ color=#333; }}

div {{ color: #333; }}

Use colon.

CSS

[x*x for x in data if x > 73]

Correct list comprehension.

Python

<br>

Self-closing.

HTML

echo 'value'

echo 'value';

Add semicolon.

PHP

if temp = 26:

if temp == 26:

Use == for comparison.

Python

let str1 = String::from("data"); let s2 = str1; println!("{{}}", str1);

let str1 = String::from("data"); let s2 = str1.clone(); println!("{{}}", str1);

Clone to avoid move.

Rust

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

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

Missing semicolon.

JavaScript

if bar = 34

if bar == 34

Use ==.

Go

age: test name: test,

age: test name: test

Remove comma.

YAML

if count = 4

if count == 4

Use ==.

MATLAB

h1 {{ font-size:33px color:red; }}

h1 {{ font-size:33px; color:red; }}

Add semicolon.

CSS

def bar puts 'message' end

Correct.

Ruby

for i=1,96 do print(i) end

Correct.

Lua

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

const user:Person = {{name:'message', age:3}};

Add missing property.

TypeScript