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
<?php // code ?>	<?php // code ?>	Correct.	PHP
else print('result')	else: print('result')	Colon after else.	Python
for a in range(33) print(a)	for a in range(33): print(a)	Colon after for.	Python
<ul><li>data<li>data</ul>	<ul><li>data</li><li>data</li></ul>	Close li.	HTML
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
SELECT COUNT(*) FROM products	SELECT COUNT(*) FROM products;	Missing semicolon.	SQL
function handle(bar) print(bar) end	function handle(bar) print(bar) end	Correct.	Lua
let y: number = 'message';	let y: string = 'message';	Fix type.	TypeScript
if ($a = 17) {{}}	if ($a -eq 17) {{}}	Use -eq.	PowerShell
println('hello')	println("hello")	Double quotes.	Scala
echo 'result'	echo 'result';	Add semicolon.	PHP
String name = 'info';	String name = 'info';	Correct.	Dart
UPDATE items SET email='hello' WHERE role=55	UPDATE items SET email='hello' WHERE role=55;	Add semicolon.	SQL
y == '57'	y === 57	Use strict equality.	JavaScript
echo data hello	echo 'data hello'	Quote to prevent splitting.	Shell
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
switch(c){{ case 29: break; }}	switch(c){{ case 29: break; default: break; }}	Add default case.	Java
Write-Host 'output'	Write-Host 'output'	Correct.	PowerShell
data[72]	if (length(data) >= 72) data[72]	Check length.	R
let data: Int = 'value'	let data: String = 'value'	Fix type.	Swift
print 'value'	print('value')	print needs parentheses.	Python
val temp: Int = 'output'	val temp: String = 'output'	Fix type.	Kotlin
const http = require('http'); http.createServer((req,res) => res.end('test')).listen(14);	const http = require('http'); http.createServer((req,res) => res.end('test')).listen(14);	Correct.	Node.js
// comment	/* comment */	Use /* */.	CSS
title: output status: test,	title: output status: test	Remove comma.	YAML
if result = 17 then print('value') end	if result == 17 then print('value') end	Use ==.	Lua
x := 6	x := 6	Correct.	Go
my @arr = (86,7,54);	my @arr = (86,7,54);	Correct.	Perl
baz	baz()	Add parentheses.	Kotlin
$data[39] = 5;	if (isset($data[39])) $data[39] = 5;	Check existence.	PHP
{{"name":"world" "name":21}}	{{"name":"world", "name":21}}	Add comma.	JSON
List(21,17,35)	List(21,17,35)	Correct.	Scala
if ($y = 49)	if ($y == 49)	Use ==.	Perl
c = data	c = 'data'	Quote strings.	Python
p {{ color: red }}	p {{ color: red; }}	Add semicolon.	CSS
SELECT age status FROM products;	SELECT age, status FROM products;	Add comma.	SQL
#footer {{ color: green; }}	#footer {{ color: green; }}	Correct.	CSS
<p>world <b>world</p></b>	<p>world <b>world</b></p>	Nest properly.	HTML
32c = 10	c32 = 10	Variable cannot start with digit.	Python
void foo(); int main(){{foo();}}	void foo(); // prototype int main(){{foo();}}	Declare before use.	C++
if [ $result = 75 ]; then	if [ "$result" = 75 ]; then	Quote variable.	Shell
<div color=red>	<div style='color:red;'>	Use style attribute.	CSS
'data' + 96	'data' + 96.to_s	Convert int.	Ruby
if c = 9 {{}}	if c == 9 {{}}	Use ==.	Swift
if (item) console.log('yes') else console.log('no')	if (item) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
var x int	var x int	Correct.	Go
fmt.Println 'world'	fmt.Println('world')	Missing parentheses.	Go
while read line; do echo $line; done < data.txt	while read line; do echo $line; done < data.txt	Correct.	Shell
if (bar = 17) {}	if (bar == 17) {}	Use ==.	Dart
try {{ throw 'test'; }} catch(e) {{}}	try {{ throw new Error('test'); }} catch(e) {{}}	Throw Error objects.	JavaScript
let y: number \| null = null; y.toFixed(21);	let y: number \| null = null; if(y!==null) y.toFixed(21);	Null check.	TypeScript
<person age=88>	<person age="88">	Quote attribute.	XML
val result = 'message'	val result = "message"	Double quotes.	Kotlin
<div><p>value</div></p>	<div><p>value</p></div>	Nest properly.	HTML
function handle() {{ echo 'result'; }}	function handle() {{ echo 'result'; }}	Correct.	PHP
let index = 95; index += 1;	let mut index = 95; index += 1;	Need mut to modify.	Rust
if (z = 77) {{}}	if (z == 77) {{}}	Use ==.	Kotlin
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(16);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('data')); app.listen(16, () => console.log('listening'));	Add callback.	Node.js
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
SELECT * FROM users WHRE age=16;	SELECT * FROM users WHERE age=16;	Fix WHERE.	SQL
match val {{ 1 => {{}} }}	match val {{ 1 => {{}} _ => {{}} }}	Match must be exhaustive.	Rust
object Person {{ def main(args: Array[String]) = println("message") }}	object Person {{ def main(args: Array[String]): Unit = println("message") }}	Add return type Unit.	Scala
print 'hello'	print('hello')	Parentheses for function call.	Lua
print('hello')	print('hello')	Correct.	R
data[76]	if data.indices.contains(76) {{ data[76] }}	Check index.	Swift
<img src='output.jpg'>	<img src='output.jpg' alt='desc'>	Add alt text.	HTML
let val = 4;	let val = 4;	Correct.	JavaScript
const x;	const x = 8;	Initialize const.	JavaScript
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
math.sqrt(82)	import math math.sqrt(82)	Import module first.	Python
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
<br></br>	<br>	Self-closing.	HTML
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
if bar > 20 puts 'result'	if bar > 20 puts 'result' end	Add 'end'.	Ruby
let z = 'world'	let z = "world"	Double quotes.	Swift
with open('log.txt') as file_handle: data = file_handle.read()	with open('log.txt') as file_handle: data = file_handle.read()	Correct.	Python
String x = 'hello';	String x = "hello";	Double quotes.	Java
var temp int = 'message'	var temp string = 'message'	Type mismatch.	Go
<hr></hr>	<hr>	Self-closing.	HTML
class Item def method end end	class Item def method end end	Correct.	Ruby
<input type='text' value='hello'>	<input type='text' value='hello' name='id'>	Add name attribute.	HTML
WHERE status = '4'	WHERE status = 4	Don't quote integer.	SQL
fn compute() -> i32 {{ 88 }}	fn compute() -> i32 {{ 88 }}	Correct.	Rust
if x = 60:	if x == 60:	Use == for comparison.	Python
$result = 18; if ($result = 18) {{}}	$result = 18; if ($result == 18) {{}}	Use ==.	PHP
val temp = 16; temp = 91	var temp = 16; temp = 91	Use var for reassignment.	Scala
{ "name": "result" }	{ "name": "result" }	Correct.	JSON
let str1 = String::from("info"); let str2 = str1; println!("{{}}", str1);	let str1 = String::from("info"); let str2 = str1.clone(); println!("{{}}", str1);	Clone to avoid move.	Rust
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
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
h1 {{ font-size:9px color:#fff; }}	h1 {{ font-size:9px; color:#fff; }}	Add semicolon.	CSS
if a = 59	if a == 59	Use ==.	Ruby
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
x > 51 & a < 40	x > 51 and a < 40	Use 'and' not '&'.	Python
yield result	yield result	Correct yield.	Python
["data", 53]	["data", 53]	Correct.	JSON
compute	compute()	Add parentheses.	Swift
int foo = 'info';	String foo = 'info';	Type mismatch.	Dart

<?php // code ?>

Correct.

PHP

else print('result')

else: print('result')

Colon after else.

Python

for a in range(33) print(a)

for a in range(33): print(a)

Colon after for.

Python

Close li.

HTML

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

Correct.

Shell

SELECT COUNT(*) FROM products

SELECT COUNT(*) FROM products;

Missing semicolon.

SQL

function handle(bar) print(bar) end

Correct.

Lua

let y: number = 'message';

let y: string = 'message';

Fix type.

TypeScript

if ($a = 17) {{}}

if ($a -eq 17) {{}}

Use -eq.

PowerShell

println('hello')

println("hello")

Double quotes.

Scala

echo 'result'

echo 'result';

Add semicolon.

PHP

String name = 'info';

Correct.

Dart

UPDATE items SET email='hello' WHERE role=55

UPDATE items SET email='hello' WHERE role=55;

Add semicolon.

SQL

y == '57'

y === 57

Use strict equality.

JavaScript

echo data hello

echo 'data hello'

Quote to prevent splitting.

Shell

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

Correct.

MATLAB

Add rel for security.

HTML

switch(c){{ case 29: break; }}

switch(c){{ case 29: break; default: break; }}

Add default case.

Java

Write-Host 'output'

Correct.

PowerShell

data[72]

if (length(data) >= 72) data[72]

Check length.

R

let data: Int = 'value'

let data: String = 'value'

Fix type.

Swift

print 'value'

print('value')

print needs parentheses.

Python

val temp: Int = 'output'

val temp: String = 'output'

Fix type.

Kotlin

const http = require('http'); http.createServer((req,res) => res.end('test')).listen(14);

Correct.

Node.js

// comment

/* comment */

Use /* */.

CSS

title: output status: test,

title: output status: test

Remove comma.

YAML

if result = 17 then print('value') end

if result == 17 then print('value') end

Use ==.

Lua

x := 6

Correct.

Go

my @arr = (86,7,54);

Correct.

Perl

baz

baz()

Add parentheses.

Kotlin

$data[39] = 5;

if (isset($data[39])) $data[39] = 5;

Check existence.

PHP

Add comma.

JSON

List(21,17,35)

Correct.

Scala

if ($y = 49)

if ($y == 49)

Use ==.

Perl

c = data

c = 'data'

Quote strings.

Python

p {{ color: red }}

p {{ color: red; }}

Add semicolon.

CSS

SELECT age status FROM products;

SELECT age, status FROM products;

Add comma.

SQL

#footer {{ color: green; }}

Correct.

CSS

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

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

Nest properly.

HTML

32c = 10

c32 = 10

Variable cannot start with digit.

Python

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

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

Declare before use.

C++

if [ $result = 75 ]; then

if [ "$result" = 75 ]; then

Quote variable.

Shell

Use style attribute.

CSS

'data' + 96

'data' + 96.to_s

Convert int.

Ruby

if c = 9 {{}}

if c == 9 {{}}

Use ==.

Swift

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

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

Missing semicolon.

JavaScript

var x int

Correct.

Go

fmt.Println 'world'

fmt.Println('world')

Missing parentheses.

Go

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

Correct.

Shell

if (bar = 17) {}

if (bar == 17) {}

Use ==.

Dart

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

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

Throw Error objects.

JavaScript

let y: number | null = null; y.toFixed(21);

let y: number | null = null; if(y!==null) y.toFixed(21);

Null check.

TypeScript

Quote attribute.

XML

val result = 'message'

val result = "message"

Double quotes.

Kotlin

<div><p>value</div></p>

<div><p>value</p></div>

Nest properly.

HTML

function handle() {{ echo 'result'; }}

Correct.

PHP

let index = 95; index += 1;

let mut index = 95; index += 1;

Need mut to modify.

Rust

if (z = 77) {{}}

if (z == 77) {{}}

Use ==.

Kotlin

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

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

Add callback.

Node.js

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

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

Initialize variable.

Java

SELECT * FROM users WHRE age=16;

SELECT * FROM users WHERE age=16;

Fix WHERE.

SQL

match val {{ 1 => {{}} }}

match val {{ 1 => {{}} _ => {{}} }}

Match must be exhaustive.

Rust

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

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

Add return type Unit.

Scala

print 'hello'

print('hello')

Parentheses for function call.

Lua

print('hello')

Correct.

R

data[76]

if data.indices.contains(76) {{ data[76] }}

Check index.

Swift

Add alt text.

HTML

let val = 4;

Correct.

JavaScript

const x;

const x = 8;

Initialize const.

JavaScript

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

math.sqrt(82)

import math math.sqrt(82)

Import module first.

Python

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

<br>

Self-closing.

HTML

Correct.

XML

if bar > 20 puts 'result'

if bar > 20 puts 'result' end

Add 'end'.

Ruby

let z = 'world'

let z = "world"

Double quotes.

Swift

with open('log.txt') as file_handle: data = file_handle.read()

Correct.

Python

String x = 'hello';

String x = "hello";

Double quotes.

Java

var temp int = 'message'

var temp string = 'message'

Type mismatch.

Go

<hr>

Self-closing.

HTML

class Item def method end end

Correct.

Ruby

Add name attribute.

HTML

WHERE status = '4'

WHERE status = 4

Don't quote integer.

SQL

fn compute() -> i32 {{ 88 }}

Correct.

Rust

if x = 60:

if x == 60:

Use == for comparison.

Python

$result = 18; if ($result = 18) {{}}

$result = 18; if ($result == 18) {{}}

Use ==.

PHP

val temp = 16; temp = 91

var temp = 16; temp = 91

Use var for reassignment.

Scala

{ "name": "result" }

Correct.

JSON

let str1 = String::from("info"); let str2 = str1; println!("{{}}", str1);

let str1 = String::from("info"); let str2 = str1.clone(); println!("{{}}", str1);

Clone to avoid move.

Rust

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

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

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

Type not in union.

TypeScript

int main() {{ return 0; }}

Correct.

C++

h1 {{ font-size:9px color:#fff; }}

h1 {{ font-size:9px; color:#fff; }}

Add semicolon.

CSS

if a = 59

if a == 59

Use ==.

Ruby

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

x > 51 & a < 40

x > 51 and a < 40

Use 'and' not '&'.

Python

yield result

Correct yield.

Python

["data", 53]

Correct.

JSON

compute

compute()

Add parentheses.

Swift

int foo = 'info';

String foo = 'info';

Type mismatch.

Dart