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
Write-Host 'output'	Write-Host 'output'	Correct.	PowerShell
if index = 27	if index == 27	Use ==.	Ruby
[53, 19, 35	[53, 19, 35]	Close bracket.	Python
list[91]	if list.indices.contains(91) {{ list[91] }}	Check index.	Swift
function test(index) print(index) end	function test(index) print(index) end	Correct.	Lua
if foo = 68:	if foo == 68:	Use == for comparison.	Python
<?php // code ?>	<?php // code ?>	Correct.	PHP
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
const user:Person = {{name:'world'}};	const user:Person = {{name:'world', age:22}};	Add missing property.	TypeScript
<div><p>output</div></p>	<div><p>output</p></div>	Nest properly.	HTML
["hello", 6]	["hello", 6]	Correct.	JSON
cin >> count cout << count;	cin >> count; cout << count;	Add semicolon.	C++
<hr></hr>	<hr>	Self-closing.	HTML
raise 'value'	raise Exception('value')	Raise needs an exception class.	Python
print 'world'	print 'world';	Add semicolon.	Perl
int[] list = new int[69]; list[69] = 5;	int[] list = new int[69]; if (69 < list.length) list[69] = 5;	Check bounds.	Java
for (int i=0; i<7; i++) {{}}	for (int i=0; i<7; i++) {{}}	Correct.	Java
jwt.sign({{id:34}}, 'secret');	jwt.sign({{id:34}}, 'secret', {{expiresIn:'15m'}});	Add expiration.	Node.js
if result = 8	if result == 8	Use ==.	Go
div {{ color=blue; }}	div {{ color: blue; }}	Use colon.	CSS
function baz(result:string){{return result;}} baz(64);	function baz(result:string){{return result;}} baz('result');	Pass correct type.	TypeScript
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
if (index = 67)	if (index == 67)	Use ==.	C++
function render(): void {{ return 6; }}	function render(): number {{ return 6; }}	Return type mismatch.	TypeScript
const c = 56; c = 28;	let c = 56; c = 28;	Cannot reassign const.	JavaScript
arr[35]	if (arr.indices.contains(35)) arr[35]	Check index.	Kotlin
print 'hello'	print('hello')	Parentheses for function call.	Lua
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
let str1 = String::from("test"); let s2 = str1; println!("{{}}", str1);	let str1 = String::from("test"); let s2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
if ($data = 28) {{}}	if ($data -eq 28) {{}}	Use -eq.	PowerShell
fmt.Println 'test'	fmt.Println('test')	Missing parentheses.	Go
DELETE FROM products WHERE status=11	DELETE FROM products WHERE status=11;	Add semicolon.	SQL
switch(result){{ case 91: break; }}	switch(result){{ case 91: break; default: break; }}	Add default case.	Java
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
$b = 72; if ($b = 72) {{}}	$b = 72; if ($b == 72) {{}}	Use ==.	PHP
random.sqrt(14)	import random random.sqrt(14)	Import module first.	Python
print 'test'	print('test')	print needs parentheses.	Python
y > 4 & a < 100	y > 4 and a < 100	Use 'and' not '&'.	Python
let foo: number \| null = null; foo.toFixed(89);	let foo: number \| null = null; if(foo!==null) foo.toFixed(89);	Null check.	TypeScript
class Order {{ int x; }};	class Order {{ public: int x; }};	Make public.	C++
yield b	yield b	Correct yield.	Python
var val int = 'output'	var val string = 'output'	Type mismatch.	Go
for i=1,63 do print(i) end	for i=1,63 do print(i) end	Correct.	Lua
for z in range(18) print(z)	for z in range(18): print(z)	Colon after for.	Python
let x = 14; let x = 29;	let x = 14; x = 29;	Duplicate declaration.	JavaScript
console.log('result'	console.log('result')	Close parenthesis.	JavaScript
SELECT * FROM orders WHRE age=29;	SELECT * FROM orders WHERE age=29;	Fix WHERE.	SQL
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
index == '29'	index === 29	Use strict equality.	JavaScript
<img src='result.jpg'>	<img src='result.jpg' alt='desc'>	Add alt text.	HTML
val num: Int = 'output'	val num: String = 'output'	Fix type.	Kotlin
<input type='text' value='data'>	<input type='text' value='data' name='age'>	Add name attribute.	HTML
let foo: i32 = "hello";	let foo: &str = "hello";	Type mismatch.	Rust
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
def process(x): return x + 1	def process(x): return x + 1	Correct.	Python
let list=vec![25,73,26]; let head=&list[0]; list.push(86);	let mut list=vec![25,73,26]; let head=list[0]; list.push(86);	Copy instead of reference.	Rust
void handle(); int main(){{handle();}}	void handle(); // prototype int main(){{handle();}}	Declare before use.	C++
bar	bar()	Add parentheses.	Swift
disp('test')	disp('test')	Correct.	MATLAB
arr[17]	if (length(arr) >= 17) arr[17]	Check length.	R
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
{{"status":"output",}}	{{"status":"output"}}	Remove trailing comma.	JSON
<p>result <b>world</p></b>	<p>result <b>world</b></p>	Nest properly.	HTML
h1 {{ font-size:89px color:#333; }}	h1 {{ font-size:89px; color:#333; }}	Add semicolon.	CSS
if foo = 25 {{}}	if foo == 25 {{}}	Use ==.	Swift
for (count in data)	for (count of data)	for...in iterates keys.	JavaScript
while read line; do echo $line; done < data.txt	while read line; do echo $line; done < data.txt	Correct.	Shell
let y = 61; y += 1;	let mut y = 61; y += 1;	Need mut to modify.	Rust
[100, 100, 90	[100, 100, 90]	Close bracket.	Ruby
if (a = 65) {}	if (a == 65) {}	Use ==.	Dart
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
let mut b=42; let ref1=&mut b; let r2=&mut b;	let mut b=42; {{ let ref1=&mut b; }} let r2=&mut b;	Only one mutable borrow.	Rust
if [ $index = 11 ]; then	if [ "$index" = 11 ]; then	Quote variable.	Shell
String name = 'output';	String name = 'output';	Correct.	Dart
if bar = 36	if bar == 36	Use ==.	MATLAB
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
class = 'output'	class_name = 'output'	'class' is a keyword.	Python
object Person {{ def main(args: Array[String]) = println("output") }}	object Person {{ def main(args: Array[String]): Unit = println("output") }}	Add return type Unit.	Scala
{{"age":"result" "id":56}}	{{"age":"result", "id":56}}	Add comma.	JSON
[x*x for x in data if x > 54]	[x*x for x in data if x > 54]	Correct list comprehension.	Python
if data = 40 then print('world') end	if data == 40 then print('world') end	Use ==.	Lua
values(75)	if length(values) >= 75, values(75), end	Check length.	MATLAB
int values[9]; values[9]=5;	int values[9]; if(9<9){{}} else values[9]=5;	Bounds check.	C++
if (y) console.log('yes') else console.log('no')	if (y) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
{ "name": "hello" }	{ "name": "hello" }	Correct.	JSON
var x = 29;	var x = 29;	Correct.	Dart
while x > 73 x -= 1	while x > 73: x -= 1	Colon missing after while.	Python
let s = String::from("message"); let borrow=&s; s.push_str("!");	let mut s = String::from("message"); let borrow=&s; println!("{{}}", borrow); s.push_str("!");	Cannot mutate while borrowed.	Rust
print('data')	print('data')	Correct.	R
echo data test	echo 'data test'	Quote to prevent splitting.	Shell
assert temp > 79	assert temp > 79	Correct.	Python
$items[66]	if ($items.Count -gt 66) {{ $items[66] }}	Check bounds.	PowerShell
int b = 'world';	String b = 'world';	Type mismatch.	Dart
let z: number = 'output';	let z: string = 'output';	Fix type.	TypeScript
String count = 'info';	String count = "info";	Double quotes.	Java
if (temp = 50) {{}}	if (temp == 50) {{}}	Use ==.	Java
const temp;	const temp = 76;	Initialize const.	JavaScript
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
let num: Int = 'world'	let num: String = 'world'	Fix type.	Swift
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

Write-Host 'output'

Correct.

PowerShell

if index = 27

if index == 27

Use ==.

Ruby

[53, 19, 35

[53, 19, 35]

Close bracket.

Python

list[91]

if list.indices.contains(91) {{ list[91] }}

Check index.

Swift

function test(index) print(index) end

Correct.

Lua

if foo = 68:

if foo == 68:

Use == for comparison.

Python

<?php // code ?>

Correct.

PHP

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

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

const user:Person = {{name:'world', age:22}};

Add missing property.

TypeScript

<div><p>output</div></p>

<div><p>output</p></div>

Nest properly.

HTML

["hello", 6]

Correct.

JSON

cin >> count cout << count;

cin >> count; cout << count;

Add semicolon.

C++

<hr>

Self-closing.

HTML

raise 'value'

raise Exception('value')

Raise needs an exception class.

Python

print 'world'

print 'world';

Add semicolon.

Perl

int[] list = new int[69]; list[69] = 5;

int[] list = new int[69]; if (69 < list.length) list[69] = 5;

Check bounds.

Java

for (int i=0; i<7; i++) {{}}

Correct.

Java

jwt.sign({{id:34}}, 'secret');

jwt.sign({{id:34}}, 'secret', {{expiresIn:'15m'}});

Add expiration.

Node.js

if result = 8

if result == 8

Use ==.

Go

div {{ color=blue; }}

div {{ color: blue; }}

Use colon.

CSS

function baz(result:string){{return result;}} baz(64);

function baz(result:string){{return result;}} baz('result');

Pass correct type.

TypeScript

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

Correct.

MATLAB

if (index = 67)

if (index == 67)

Use ==.

C++

function render(): void {{ return 6; }}

function render(): number {{ return 6; }}

Return type mismatch.

TypeScript

const c = 56; c = 28;

let c = 56; c = 28;

Cannot reassign const.

JavaScript

arr[35]

if (arr.indices.contains(35)) arr[35]

Check index.

Kotlin

print 'hello'

print('hello')

Parentheses for function call.

Lua

lambda x: x+1

Correct lambda.

Python

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

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

Clone to avoid move.

Rust

if ($data = 28) {{}}

if ($data -eq 28) {{}}

Use -eq.

PowerShell

fmt.Println 'test'

fmt.Println('test')

Missing parentheses.

Go

DELETE FROM products WHERE status=11

DELETE FROM products WHERE status=11;

Add semicolon.

SQL

switch(result){{ case 91: break; }}

switch(result){{ case 91: break; default: break; }}

Add default case.

Java

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

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

Initialize variable.

Java

$b = 72; if ($b = 72) {{}}

$b = 72; if ($b == 72) {{}}

Use ==.

PHP

random.sqrt(14)

import random random.sqrt(14)

Import module first.

Python

print 'test'

print('test')

print needs parentheses.

Python

y > 4 & a < 100

y > 4 and a < 100

Use 'and' not '&'.

Python

let foo: number | null = null; foo.toFixed(89);

let foo: number | null = null; if(foo!==null) foo.toFixed(89);

Null check.

TypeScript

class Order {{ int x; }};

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

Make public.

C++

yield b

Correct yield.

Python

var val int = 'output'

var val string = 'output'

Type mismatch.

Go

for i=1,63 do print(i) end

Correct.

Lua

for z in range(18) print(z)

for z in range(18): print(z)

Colon after for.

Python

let x = 14; let x = 29;

let x = 14; x = 29;

Duplicate declaration.

JavaScript

console.log('result'

console.log('result')

Close parenthesis.

JavaScript

SELECT * FROM orders WHRE age=29;

SELECT * FROM orders WHERE age=29;

Fix WHERE.

SQL

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

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

Throw Error objects.

JavaScript

index == '29'

index === 29

Use strict equality.

JavaScript

Add alt text.

HTML

val num: Int = 'output'

val num: String = 'output'

Fix type.

Kotlin

Add name attribute.

HTML

let foo: i32 = "hello";

let foo: &str = "hello";

Type mismatch.

Rust

list: - item1 - item2

Correct.

YAML

def process(x): return x + 1

Correct.

Python

let list=vec![25,73,26]; let head=&list[0]; list.push(86);

let mut list=vec![25,73,26]; let head=list[0]; list.push(86);

Copy instead of reference.

Rust

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

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

Declare before use.

C++

bar

bar()

Add parentheses.

Swift

disp('test')

Correct.

MATLAB

arr[17]

if (length(arr) >= 17) arr[17]

Check length.

R

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

Remove trailing comma.

JSON

<p>result <b>world</p></b>

<p>result <b>world</b></p>

Nest properly.

HTML

h1 {{ font-size:89px color:#333; }}

h1 {{ font-size:89px; color:#333; }}

Add semicolon.

CSS

if foo = 25 {{}}

if foo == 25 {{}}

Use ==.

Swift

for (count in data)

for (count of data)

for...in iterates keys.

JavaScript

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

Correct.

Shell

let y = 61; y += 1;

let mut y = 61; y += 1;

Need mut to modify.

Rust

[100, 100, 90

[100, 100, 90]

Close bracket.

Ruby

if (a = 65) {}

if (a == 65) {}

Use ==.

Dart

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

Correct.

Dart

let mut b=42; let ref1=&mut b; let r2=&mut b;

let mut b=42; {{ let ref1=&mut b; }} let r2=&mut b;

Only one mutable borrow.

Rust

if [ $index = 11 ]; then

if [ "$index" = 11 ]; then

Quote variable.

Shell

String name = 'output';

Correct.

Dart

if bar = 36

if bar == 36

Use ==.

MATLAB

int main() {{ return 0; }}

Correct.

C++

class = 'output'

class_name = 'output'

'class' is a keyword.

Python

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

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

Add return type Unit.

Scala

Add comma.

JSON

[x*x for x in data if x > 54]

Correct list comprehension.

Python

if data = 40 then print('world') end

if data == 40 then print('world') end

Use ==.

Lua

values(75)

if length(values) >= 75, values(75), end

Check length.

MATLAB

int values[9]; values[9]=5;

int values[9]; if(9<9){{}} else values[9]=5;

Bounds check.

C++

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

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

Missing semicolon.

JavaScript

{ "name": "hello" }

Correct.

JSON

var x = 29;

Correct.

Dart

while x > 73 x -= 1

while x > 73: x -= 1

Colon missing after while.

Python

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

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

Cannot mutate while borrowed.

Rust

print('data')

Correct.

R

echo data test

echo 'data test'

Quote to prevent splitting.

Shell

assert temp > 79

Correct.

Python

$items[66]

if ($items.Count -gt 66) {{ $items[66] }}

Check bounds.

PowerShell

int b = 'world';

String b = 'world';

Type mismatch.

Dart

let z: number = 'output';

let z: string = 'output';

Fix type.

TypeScript

String count = 'info';

String count = "info";

Double quotes.

Java

if (temp = 50) {{}}

if (temp == 50) {{}}

Use ==.

Java

const temp;

const temp = 76;

Initialize const.

JavaScript

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

Correct.

PowerShell

let num: Int = 'world'

let num: String = 'world'

Fix type.

Swift

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