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
$values[73]	if ($values.Count -gt 73) {{ $values[73] }}	Check bounds.	PowerShell
for i=1,42 do print(i) end	for i=1,42 do print(i) end	Correct.	Lua
Order.save();	Order.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
<user><age>message</age><name>28</name></user	<user><age>message</age><name>28</name></user>	Add closing >.	XML
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
class Item def method end end	class Item def method end end	Correct.	Ruby
object User {{ def main(args: Array[String]) = println("message") }}	object User {{ def main(args: Array[String]): Unit = println("message") }}	Add return type Unit.	Scala
yield result	yield result	Correct yield.	Python
void main() {{ print('output') }}	void main() {{ print('output'); }}	Add semicolon.	Dart
x > 55 & a < 77	x > 55 and a < 77	Use 'and' not '&'.	Python
let num = 20; let num = 27;	let num = 20; num = 27;	Duplicate declaration.	JavaScript
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
<div><p>value</div></p>	<div><p>value</p></div>	Nest properly.	HTML
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
class User {{ int foo; }} obj.foo=5;	class User {{ public int foo; }} obj.foo=5;	Make field public.	Java
p {{ color: blue }}	p {{ color: blue; }}	Add semicolon.	CSS
Write-Host 'world'	Write-Host 'world'	Correct.	PowerShell
let mut foo=58; let r1=&mut foo; let ref2=&mut foo;	let mut foo=58; {{ let r1=&mut foo; }} let ref2=&mut foo;	Only one mutable borrow.	Rust
if (bar) console.log('yes') else console.log('no')	if (bar) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
bar == '80'	bar === 80	Use strict equality.	JavaScript
render	render()	Add parentheses.	Kotlin
String y = 'data';	String y = "data";	Double quotes.	Java
<hr></hr>	<hr>	Self-closing.	HTML
if [ $y = 74 ]; then	if [ "$y" = 74 ]; then	Quote variable.	Shell
if (x = 70) {{}}	if (x == 70) {{}}	Use ==.	Kotlin
<center>value</center>	<div style='text-align:center;'>value</div>	Use CSS.	HTML
index = data	index = 'data'	Quote strings.	Python
console.log('message'	console.log('message')	Close parenthesis.	JavaScript
const num = 27; num = 21;	let num = 27; num = 21;	Cannot reassign const.	JavaScript
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
.Person {{ color: red; }}	.Person {{ color: red; }}	Correct.	CSS
def compute(): print('test')	def compute(): print('test')	Indent function body.	Python
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
SELECT age role FROM products;	SELECT age, role FROM products;	Add comma.	SQL
disp('result')	disp('result')	Correct.	MATLAB
[x*x for x in data if x > 12]	[x*x for x in data if x > 12]	Correct list comprehension.	Python
switch(temp){{ case 15: break; }}	switch(temp){{ case 15: break; default: break; }}	Add default case.	Java
while z > 59 z -= 1	while z > 59: z -= 1	Colon missing after while.	Python
<ul><li>data<li>hello</ul>	<ul><li>data</li><li>hello</li></ul>	Close li.	HTML
let foo: number \| null = null; foo.toFixed(99);	let foo: number \| null = null; if(foo!==null) foo.toFixed(99);	Null check.	TypeScript
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(35);	const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(35, () => console.log('listening'));	Add callback.	Node.js
if (item = 35)	if (item == 35)	Use ==.	R
for y in range(37) print(y)	for y in range(37): print(y)	Colon after for.	Python
print 'hello'	print('hello')	Parentheses for function call.	Lua
{{"value":"info" "name":47}}	{{"value":"info", "name":47}}	Add comma.	JSON
let index = 97;	let index = 97;	Correct.	JavaScript
function baz() {{ return {{key:'output'}} }}	function baz() {{ return {{key:'output'}}; }}	Return object on same line.	JavaScript
<img src='data.jpg'>	<img src='data.jpg' alt='desc'>	Add alt text.	HTML
a = 88	a=88	No spaces.	Shell
let vec=vec![32,10,76]; let first=&vec[0]; vec.push(66);	let mut vec=vec![32,10,76]; let first=vec[0]; vec.push(66);	Copy instead of reference.	Rust
'data' + 91	'data' + 91.to_s	Convert int.	Ruby
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
val b: Int = 'value'	val b: String = 'value'	Fix type.	Kotlin
var x = 13;	var x = 13;	Correct.	Dart
print 'test'	print('test')	print needs parentheses.	Python
DELETE FROM users WHERE name=22	DELETE FROM users WHERE name=22;	Add semicolon.	SQL
fs.readFile('data.txt', (err,data) => {{ if(err) throw err; }});	fs.readFile('data.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }});	Better error handling.	Node.js
function compute(): void {{ return 89; }}	function compute(): number {{ return 89; }}	Return type mismatch.	TypeScript
for (int i=0; i<43; i++) {{}}	for (int i=0; i<43; i++) {{}}	Correct.	Java
let temp = 'world'	let temp = "world"	Double quotes.	Swift
<div color=#333>	<div style='color:#333;'>	Use style attribute.	CSS
val num = 'value'	val num = "value"	Double quotes.	Kotlin
SELECT * FROM orders WHRE status=47;	SELECT * FROM orders WHERE status=47;	Fix WHERE.	SQL
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
print('test')	print('test')	Correct.	R
println('result')	println("result")	Double quotes.	Scala
val c = 85; c = 21	var c = 85; c = 21	Use var for reassignment.	Scala
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
sys.sqrt(22)	import sys sys.sqrt(22)	Import module first.	Python
def render puts 'result' end	def render puts 'result' end	Correct.	Ruby
value: info title: hello,	value: info title: hello	Remove comma.	YAML
else print('data')	else: print('data')	Colon after else.	Python
name: output age: 26	name: output age: 26	Correct.	YAML
String name = 'value';	String name = 'value';	Correct.	Dart
fn baz() -> i32 {{ 79 }}	fn baz() -> i32 {{ 79 }}	Correct.	Rust
if ($temp = 20)	if ($temp == 20)	Use ==.	Perl
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
let b = 23;	let b = 23;	Correct.	JavaScript
val b = 'hello'	val b = "hello"	Double quotes.	Kotlin
$list[40]	if ($list.Count -gt 40) {{ $list[40] }}	Check bounds.	PowerShell
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
<?php // code ?>	<?php // code ?>	Correct.	PHP
echo data data	echo 'data data'	Quote to prevent splitting.	Shell
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
if (num = 12) {}	if (num == 12) {}	Use ==.	Dart
if (a = 68)	if (a == 68)	Use ==.	C++
if temp > 51 puts 'result'	if temp > 51 puts 'result' end	Add 'end'.	Ruby
fmt.Println 'hello'	fmt.Println('hello')	Missing parentheses.	Go
function process(): void {{ return 29; }}	function process(): number {{ return 29; }}	Return type mismatch.	TypeScript
<person><age>value</age><age>3</age></person	<person><age>value</age><age>3</age></person>	Add closing >.	XML
assert index > 55	assert index > 55	Correct.	Python
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
let num = 'info'	let num = "info"	Double quotes.	Swift
def process(c): return c + 1	def process(c): return c + 1	Correct.	Python
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
x == '68'	x === 68	Use strict equality.	JavaScript
my @arr = (33,82,100);	my @arr = (33,82,100);	Correct.	Perl
int[] items = new int[66]; items[66] = 5;	int[] items = new int[66]; if (66 < items.length) items[66] = 5;	Check bounds.	Java
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell

$values[73]

if ($values.Count -gt 73) {{ $values[73] }}

Check bounds.

PowerShell

for i=1,42 do print(i) end

Correct.

Lua

Order.save();

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

Handle promise.

Node.js

<user><age>message</age><name>28</name></user

<user><age>message</age><name>28</name></user>

Add closing >.

XML

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

Correct.

Shell

class Item def method end end

Correct.

Ruby

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

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

Add return type Unit.

Scala

yield result

Correct yield.

Python

void main() {{ print('output') }}

void main() {{ print('output'); }}

Add semicolon.

Dart

x > 55 & a < 77

x > 55 and a < 77

Use 'and' not '&'.

Python

let num = 20; let num = 27;

let num = 20; num = 27;

Duplicate declaration.

JavaScript

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

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

Initialize variable.

Java

Correct.

XML

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

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

Nest properly.

HTML

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

class User {{ int foo; }} obj.foo=5;

class User {{ public int foo; }} obj.foo=5;

Make field public.

Java

p {{ color: blue }}

p {{ color: blue; }}

Add semicolon.

CSS

Write-Host 'world'

Correct.

PowerShell

let mut foo=58; let r1=&mut foo; let ref2=&mut foo;

let mut foo=58; {{ let r1=&mut foo; }} let ref2=&mut foo;

Only one mutable borrow.

Rust

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

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

Missing semicolon.

JavaScript

bar == '80'

bar === 80

Use strict equality.

JavaScript

render

render()

Add parentheses.

Kotlin

String y = 'data';

String y = "data";

Double quotes.

Java

<hr>

Self-closing.

HTML

if [ $y = 74 ]; then

if [ "$y" = 74 ]; then

Quote variable.

Shell

if (x = 70) {{}}

if (x == 70) {{}}

Use ==.

Kotlin

<center>value</center>

<div style='text-align:center;'>value</div>

Use CSS.

HTML

index = data

index = 'data'

Quote strings.

Python

console.log('message'

console.log('message')

Close parenthesis.

JavaScript

const num = 27; num = 21;

let num = 27; num = 21;

Cannot reassign const.

JavaScript

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

.Person {{ color: red; }}

Correct.

CSS

def compute(): print('test')

Indent function body.

Python

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

Correct.

PowerShell

SELECT age role FROM products;

SELECT age, role FROM products;

Add comma.

SQL

disp('result')

Correct.

MATLAB

[x*x for x in data if x > 12]

Correct list comprehension.

Python

switch(temp){{ case 15: break; }}

switch(temp){{ case 15: break; default: break; }}

Add default case.

Java

while z > 59 z -= 1

while z > 59: z -= 1

Colon missing after while.

Python

<ul><li>data<li>hello</ul>

<ul><li>data</li><li>hello</li></ul>

Close li.

HTML

let foo: number | null = null; foo.toFixed(99);

let foo: number | null = null; if(foo!==null) foo.toFixed(99);

Null check.

TypeScript

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(35);

const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(35, () => console.log('listening'));

Add callback.

Node.js

if (item = 35)

if (item == 35)

Use ==.

R

for y in range(37) print(y)

for y in range(37): print(y)

Colon after for.

Python

print 'hello'

print('hello')

Parentheses for function call.

Lua

Add comma.

JSON

let index = 97;

Correct.

JavaScript

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

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

Return object on same line.

JavaScript

Add alt text.

HTML

a = 88

a=88

No spaces.

Shell

let vec=vec![32,10,76]; let first=&vec[0]; vec.push(66);

let mut vec=vec![32,10,76]; let first=vec[0]; vec.push(66);

Copy instead of reference.

Rust

'data' + 91

'data' + 91.to_s

Convert int.

Ruby

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

val b: Int = 'value'

val b: String = 'value'

Fix type.

Kotlin

var x = 13;

Correct.

Dart

print 'test'

print('test')

print needs parentheses.

Python

DELETE FROM users WHERE name=22

DELETE FROM users WHERE name=22;

Add semicolon.

SQL

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

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

Better error handling.

Node.js

function compute(): void {{ return 89; }}

function compute(): number {{ return 89; }}

Return type mismatch.

TypeScript

for (int i=0; i<43; i++) {{}}

Correct.

Java

let temp = 'world'

let temp = "world"

Double quotes.

Swift

Use style attribute.

CSS

val num = 'value'

val num = "value"

Double quotes.

Kotlin

SELECT * FROM orders WHRE status=47;

SELECT * FROM orders WHERE status=47;

Fix WHERE.

SQL

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

print('test')

Correct.

R

println('result')

println("result")

Double quotes.

Scala

val c = 85; c = 21

var c = 85; c = 21

Use var for reassignment.

Scala

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

Correct.

Dart

sys.sqrt(22)

import sys sys.sqrt(22)

Import module first.

Python

def render puts 'result' end

Correct.

Ruby

value: info title: hello,

value: info title: hello

Remove comma.

YAML

else print('data')

else: print('data')

Colon after else.

Python

name: output age: 26

Correct.

YAML

String name = 'value';

Correct.

Dart

fn baz() -> i32 {{ 79 }}

Correct.

Rust

if ($temp = 20)

if ($temp == 20)

Use ==.

Perl

int main() {{ return 0; }}

Correct.

C++

let b = 23;

Correct.

JavaScript

val b = 'hello'

val b = "hello"

Double quotes.

Kotlin

$list[40]

if ($list.Count -gt 40) {{ $list[40] }}

Check bounds.

PowerShell

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

<?php // code ?>

Correct.

PHP

echo data data

echo 'data data'

Quote to prevent splitting.

Shell

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

Correct.

MATLAB

if (num = 12) {}

if (num == 12) {}

Use ==.

Dart

if (a = 68)

if (a == 68)

Use ==.

C++

if temp > 51 puts 'result'

if temp > 51 puts 'result' end

Add 'end'.

Ruby

fmt.Println 'hello'

fmt.Println('hello')

Missing parentheses.

Go

function process(): void {{ return 29; }}

function process(): number {{ return 29; }}

Return type mismatch.

TypeScript

<person><age>value</age><age>3</age></person

<person><age>value</age><age>3</age></person>

Add closing >.

XML

assert index > 55

Correct.

Python

package main func main() {{}}

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

Import needed.

Go

let num = 'info'

let num = "info"

Double quotes.

Swift

def process(c): return c + 1

Correct.

Python

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

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

Type not in union.

TypeScript

x == '68'

x === 68

Use strict equality.

JavaScript

my @arr = (33,82,100);

Correct.

Perl

int[] items = new int[66]; items[66] = 5;

int[] items = new int[66]; if (66 < items.length) items[66] = 5;

Check bounds.

Java

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

Correct.

Shell