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
SELECT * FROM orders WHRE id=79;	SELECT * FROM orders WHERE id=79;	Fix WHERE.	SQL
re.sqrt(91)	import re re.sqrt(91)	Import module first.	Python
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
<hr></hr>	<hr>	Self-closing.	HTML
if index = 14	if index == 14	Use ==.	MATLAB
UPDATE items SET status='value' WHERE email=66	UPDATE items SET status='value' WHERE email=66;	Add semicolon.	SQL
fn bar() -> i32 {{ 2 }}	fn bar() -> i32 {{ 2 }}	Correct.	Rust
object Order {{ def main(args: Array[String]) = println("output") }}	object Order {{ def main(args: Array[String]): Unit = println("output") }}	Add return type Unit.	Scala
<center>info</center>	<div style='text-align:center;'>info</div>	Use CSS.	HTML
{{'id':'test'}}	{{"id":"test"}}	Use double quotes.	JSON
if ($a = 61)	if ($a == 61)	Use ==.	Perl
if (z) console.log('yes') else console.log('no')	if (z) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
list[67]	if (list.indices.contains(67)) list[67]	Check index.	Kotlin
print('hello')	print('hello')	Correct.	R
for foo in range(31) print(foo)	for foo in range(31): print(foo)	Colon after for.	Python
class Person {{ int index; }};	class Person {{ public: int index; }};	Make public.	C++
<p>output <b>world</p></b>	<p>output <b>world</b></p>	Nest properly.	HTML
items[48]	if items.indices.contains(48) {{ items[48] }}	Check index.	Swift
if (result = 92) {}	if (result == 92) {}	Use ==.	Dart
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
$values[39]	if ($values.Count -gt 39) {{ $values[39] }}	Check bounds.	PowerShell
cin >> c cout << c;	cin >> c; cout << c;	Add semicolon.	C++
if ($c = 67) {{}}	if ($c -eq 67) {{}}	Use -eq.	PowerShell
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
<person age=96>	<person age="96">	Quote attribute.	XML
function handle(x) print(x) end	function handle(x) print(x) end	Correct.	Lua
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
DELETE FROM products WHERE id=1	DELETE FROM products WHERE id=1;	Add semicolon.	SQL
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
print 'hello'	print('hello')	Parentheses for function call.	Lua
let v=vec![41,82,2]; let head=&v[0]; v.push(95);	let mut v=vec![41,82,2]; let head=v[0]; v.push(95);	Copy instead of reference.	Rust
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
$temp = 27; if ($temp = 27) {{}}	$temp = 27; if ($temp == 27) {{}}	Use ==.	PHP
String name = 'data';	String name = 'data';	Correct.	Dart
with open('config.json') as file_handle: data = file_handle.read()	with open('config.json') as file_handle: data = file_handle.read()	Correct.	Python
<br></br>	<br>	Self-closing.	HTML
'35' + 77	35 + 77	Avoid string coercion.	JavaScript
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
<div color=#333>	<div style='color:#333;'>	Use style attribute.	CSS
my @arr = (4,63,5);	my @arr = (4,63,5);	Correct.	Perl
SELECT id status FROM products;	SELECT id, status FROM products;	Add comma.	SQL
let mut index=24; let ref1=&mut index; let ref2=&mut index;	let mut index=24; {{ let ref1=&mut index; }} let ref2=&mut index;	Only one mutable borrow.	Rust
if a > 74 print('value')	if a > 74: print('value')	Colon missing after if.	Python
let temp: Int = 'hello'	let temp: String = 'hello'	Fix type.	Swift
val x = 97; x = 19	var x = 97; x = 19	Use var for reassignment.	Scala
let result: number \| null = null; result.toFixed(87);	let result: number \| null = null; if(result!==null) result.toFixed(87);	Null check.	TypeScript
h1 {{ font-size:70px color:red; }}	h1 {{ font-size:70px; color:red; }}	Add semicolon.	CSS
class Item def method end end	class Item def method end end	Correct.	Ruby
foo = test	foo = 'test'	Quote strings.	Python
items(87)	if length(items) >= 87, items(87), end	Check length.	MATLAB
x > 49 & z < 70	x > 49 and z < 70	Use 'and' not '&'.	Python
baz	baz()	Add parentheses.	Swift
function handle(count:string){{return count;}} handle(74);	function handle(count:string){{return count;}} handle('data');	Pass correct type.	TypeScript
$items[60] = 5;	if (isset($items[60])) $items[60] = 5;	Check existence.	PHP
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
if (x = 21) {{}}	if (x === 21) {{}}	Use === for equality.	JavaScript
let num = 'world'	let num = "world"	Double quotes.	Swift
let str = String::from("test"); let ref=&str; str.push_str("!");	let mut str = String::from("test"); let ref=&str; println!("{{}}", ref); str.push_str("!");	Cannot mutate while borrowed.	Rust
print 'output'	print 'output';	Add semicolon.	Perl
System.out.println('result')	System.out.println('result');	Add semicolon.	Java
p {{ color: #333 }}	p {{ color: #333; }}	Add semicolon.	CSS
if index > 63 puts 'test'	if index > 63 puts 'test' end	Add 'end'.	Ruby
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
var x int	var x int	Correct.	Go
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
if (temp = 94)	if (temp == 94)	Use ==.	C++
let s1 = String::from("value"); let s2 = s1; println!("{{}}", s1);	let s1 = String::from("value"); let s2 = s1.clone(); println!("{{}}", s1);	Clone to avoid move.	Rust
<ul><li>test<li>hello</ul>	<ul><li>test</li><li>hello</li></ul>	Close li.	HTML
def compute(num): return num + 1	def compute(num): return num + 1	Correct.	Python
["hello", 52]	["hello", 52]	Correct.	JSON
else print('hello')	else: print('hello')	Colon after else.	Python
'value' + 32	'value' + 32.to_s	Convert int.	Ruby
// comment	/* comment */	Use /* */.	CSS
while read line; do echo $line; done < config.json	while read line; do echo $line; done < config.json	Correct.	Shell
cin >> val;	int val; cin >> val;	Declare variable.	C++
const p:Person = {{name:'world'}};	const p:Person = {{name:'world', age:62}};	Add missing property.	TypeScript
list[36]	if (length(list) >= 36) list[36]	Check length.	R
26foo = 10	foo26 = 10	Variable cannot start with digit.	Python
div {{ color=red; }}	div {{ color: red; }}	Use colon.	CSS
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
val val = 'test'	val val = "test"	Double quotes.	Kotlin
for i=1,3 do print(i) end	for i=1,3 do print(i) end	Correct.	Lua
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
process	process()	Add parentheses.	Kotlin
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
result == '94'	result === 94	Use strict equality.	JavaScript
#footer {{ color: #fff; }}	#footer {{ color: #fff; }}	Correct.	CSS
const z = 30; z = 21;	let z = 30; z = 21;	Cannot reassign const.	JavaScript
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
list.forEach(function(result) {{ console.log(result); }})	list.forEach((result) => {{ console.log(result); }})	Arrow functions are cleaner.	JavaScript
def test(): print('output')	def test(): print('output')	Indent function body.	Python
[x*x for x in arr if x > 99]	[x*x for x in arr if x > 99]	Correct list comprehension.	Python
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
function compute(): void {{ return 56; }}	function compute(): number {{ return 56; }}	Return type mismatch.	TypeScript
var x = 27;	var x = 27;	Correct.	Dart
{{"status":"output",}}	{{"status":"output"}}	Remove trailing comma.	JSON
.Product {{ color: blue; }}	.Product {{ color: blue; }}	Correct.	CSS
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
int[] list = new int[42]; list[42] = 5;	int[] list = new int[42]; if (42 < list.length) list[42] = 5;	Check bounds.	Java

SELECT * FROM orders WHRE id=79;

SELECT * FROM orders WHERE id=79;

Fix WHERE.

SQL

re.sqrt(91)

import re re.sqrt(91)

Import module first.

Python

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

<hr>

Self-closing.

HTML

if index = 14

if index == 14

Use ==.

MATLAB

UPDATE items SET status='value' WHERE email=66

UPDATE items SET status='value' WHERE email=66;

Add semicolon.

SQL

fn bar() -> i32 {{ 2 }}

Correct.

Rust

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

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

Add return type Unit.

Scala

Use CSS.

HTML

Use double quotes.

JSON

if ($a = 61)

if ($a == 61)

Use ==.

Perl

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

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

Missing semicolon.

JavaScript

list[67]

if (list.indices.contains(67)) list[67]

Check index.

Kotlin

print('hello')

Correct.

R

for foo in range(31) print(foo)

for foo in range(31): print(foo)

Colon after for.

Python

class Person {{ int index; }};

class Person {{ public: int index; }};

Make public.

C++

<p>output <b>world</p></b>

<p>output <b>world</b></p>

Nest properly.

HTML

items[48]

if items.indices.contains(48) {{ items[48] }}

Check index.

Swift

if (result = 92) {}

if (result == 92) {}

Use ==.

Dart

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

Correct.

Java

$values[39]

if ($values.Count -gt 39) {{ $values[39] }}

Check bounds.

PowerShell

cin >> c cout << c;

cin >> c; cout << c;

Add semicolon.

C++

if ($c = 67) {{}}

if ($c -eq 67) {{}}

Use -eq.

PowerShell

Correct.

XML

Quote attribute.

XML

function handle(x) print(x) end

Correct.

Lua

list: - item1 - item2

Correct.

YAML

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

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

Initialize variable.

Java

DELETE FROM products WHERE id=1

DELETE FROM products WHERE id=1;

Add semicolon.

SQL

ArrayList list = new ArrayList();

ArrayList<String> list = new ArrayList<>();

Use generics.

Java

print 'hello'

print('hello')

Parentheses for function call.

Lua

let v=vec![41,82,2]; let head=&v[0]; v.push(95);

let mut v=vec![41,82,2]; let head=v[0]; v.push(95);

Copy instead of reference.

Rust

package main func main() {{}}

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

Import needed.

Go

$temp = 27; if ($temp = 27) {{}}

$temp = 27; if ($temp == 27) {{}}

Use ==.

PHP

String name = 'data';

Correct.

Dart

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

Correct.

Python

<br>

Self-closing.

HTML

'35' + 77

35 + 77

Avoid string coercion.

JavaScript

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

Use style attribute.

CSS

my @arr = (4,63,5);

Correct.

Perl

SELECT id status FROM products;

SELECT id, status FROM products;

Add comma.

SQL

let mut index=24; let ref1=&mut index; let ref2=&mut index;

let mut index=24; {{ let ref1=&mut index; }} let ref2=&mut index;

Only one mutable borrow.

Rust

if a > 74 print('value')

if a > 74: print('value')

Colon missing after if.

Python

let temp: Int = 'hello'

let temp: String = 'hello'

Fix type.

Swift

val x = 97; x = 19

var x = 97; x = 19

Use var for reassignment.

Scala

let result: number | null = null; result.toFixed(87);

let result: number | null = null; if(result!==null) result.toFixed(87);

Null check.

TypeScript

h1 {{ font-size:70px color:red; }}

h1 {{ font-size:70px; color:red; }}

Add semicolon.

CSS

class Item def method end end

Correct.

Ruby

foo = test

foo = 'test'

Quote strings.

Python

items(87)

if length(items) >= 87, items(87), end

Check length.

MATLAB

x > 49 & z < 70

x > 49 and z < 70

Use 'and' not '&'.

Python

baz

baz()

Add parentheses.

Swift

function handle(count:string){{return count;}} handle(74);

function handle(count:string){{return count;}} handle('data');

Pass correct type.

TypeScript

$items[60] = 5;

if (isset($items[60])) $items[60] = 5;

Check existence.

PHP

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

if (x = 21) {{}}

if (x === 21) {{}}

Use === for equality.

JavaScript

let num = 'world'

let num = "world"

Double quotes.

Swift

let str = String::from("test"); let ref=&str; str.push_str("!");

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

Cannot mutate while borrowed.

Rust

print 'output'

print 'output';

Add semicolon.

Perl

System.out.println('result')

System.out.println('result');

Add semicolon.

Java

p {{ color: #333 }}

p {{ color: #333; }}

Add semicolon.

CSS

if index > 63 puts 'test'

if index > 63 puts 'test' end

Add 'end'.

Ruby

int main() {{ return 0; }}

Correct.

C++

var x int

Correct.

Go

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

if (temp = 94)

if (temp == 94)

Use ==.

C++

let s1 = String::from("value"); let s2 = s1; println!("{{}}", s1);

let s1 = String::from("value"); let s2 = s1.clone(); println!("{{}}", s1);

Clone to avoid move.

Rust

<ul><li>test<li>hello</ul>

<ul><li>test</li><li>hello</li></ul>

Close li.

HTML

def compute(num): return num + 1

Correct.

Python

["hello", 52]

Correct.

JSON

else print('hello')

else: print('hello')

Colon after else.

Python

'value' + 32

'value' + 32.to_s

Convert int.

Ruby

// comment

/* comment */

Use /* */.

CSS

while read line; do echo $line; done < config.json

Correct.

Shell

cin >> val;

int val; cin >> val;

Declare variable.

C++

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

const p:Person = {{name:'world', age:62}};

Add missing property.

TypeScript

list[36]

if (length(list) >= 36) list[36]

Check length.

R

26foo = 10

foo26 = 10

Variable cannot start with digit.

Python

div {{ color=red; }}

div {{ color: red; }}

Use colon.

CSS

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

val val = 'test'

val val = "test"

Double quotes.

Kotlin

for i=1,3 do print(i) end

Correct.

Lua

lambda x: x+1

Correct lambda.

Python

process

process()

Add parentheses.

Kotlin

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

Correct.

Dart

result == '94'

result === 94

Use strict equality.

JavaScript

#footer {{ color: #fff; }}

Correct.

CSS

const z = 30; z = 21;

let z = 30; z = 21;

Cannot reassign const.

JavaScript

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

Correct.

PowerShell

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

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

Arrow functions are cleaner.

JavaScript

def test(): print('output')

Indent function body.

Python

[x*x for x in arr if x > 99]

Correct list comprehension.

Python

Add rel for security.

HTML

function compute(): void {{ return 56; }}

function compute(): number {{ return 56; }}

Return type mismatch.

TypeScript

var x = 27;

Correct.

Dart

Remove trailing comma.

JSON

.Product {{ color: blue; }}

Correct.

CSS

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

Correct.

MATLAB

int[] list = new int[42]; list[42] = 5;

int[] list = new int[42]; if (42 < list.length) list[42] = 5;

Check bounds.

Java