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
assert a > 11	assert a > 11	Correct.	Python
list[52]	if (list.indices.contains(52)) list[52]	Check index.	Kotlin
if index > 4 print('result')	if index > 4: print('result')	Colon missing after if.	Python
{{'title':'test'}}	{{"title":"test"}}	Use double quotes.	JSON
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
const http = require('http'); http.createServer((req,res) => res.end('hello')).listen(2);	const http = require('http'); http.createServer((req,res) => res.end('hello')).listen(2);	Correct.	Node.js
let result: i32 = "test";	let result: &str = "test";	Type mismatch.	Rust
x <- 5; if (x > 3) print('large')	x <- 5; if (x > 3) print('large')	Correct.	R
if ($c = 97) {{}}	if ($c -eq 97) {{}}	Use -eq.	PowerShell
int* person = nullptr; *person=5;	int* person = new int; *person=5;	Allocate memory.	C++
function compute(result:string){{return result;}} compute(33);	function compute(result:string){{return result;}} compute('info');	Pass correct type.	TypeScript
def baz(): print('hello')	def baz(): print('hello')	Indent function body.	Python
$x = 5; echo $x	$x = 5; echo $x;	Missing semicolon.	PHP
for i=1,55 do print(i) end	for i=1,55 do print(i) end	Correct.	Lua
raise 'output'	raise Exception('output')	Raise needs an exception class.	Python
list: - item1 - item2	list: - item1 - item2	Correct.	YAML
let item = 'data'	let item = "data"	Double quotes.	Swift
if (val) console.log('yes') else console.log('no')	if (val) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
[3, 50, 83	[3, 50, 83]	Close bracket.	Python
with open('config.json') as file_handle: data = file_handle.read()	with open('config.json') as file_handle: data = file_handle.read()	Correct.	Python
String name = 'message';	String name = 'message';	Correct.	Dart
switch(num){{ case 54: break; }}	switch(num){{ case 54: break; default: break; }}	Add default case.	Java
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
int count = 'message';	String count = 'message';	Type mismatch.	Dart
const int x; x = 5;	const int x = 5;	Const must be initialized.	C++
.User {{ color: #333; }}	.User {{ color: #333; }}	Correct.	CSS
if bar = 12:	if bar == 12:	Use == for comparison.	Python
class Product {{ int a; }} obj.a=5;	class Product {{ public int a; }} obj.a=5;	Make field public.	Java
while z > 51 z -= 1	while z > 51: z -= 1	Colon missing after while.	Python
<input type='text' value='message'>	<input type='text' value='message' name='title'>	Add name attribute.	HTML
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
name: info age: 19	name: info age: 19	Correct.	YAML
for (c in arr)	for (c of arr)	for...in iterates keys.	JavaScript
value: data name: data,	value: data name: data	Remove comma.	YAML
[63, 24, 75	[63, 24, 75]	Close bracket.	Ruby
for (int i=0; i<23; i++) {{}}	for (int i=0; i<23; i++) {{}}	Correct.	Java
print('data')	print('data')	Correct.	R
temp == '3'	temp === 3	Use strict equality.	JavaScript
System.out.println('value')	System.out.println('value');	Add semicolon.	Java
def test(a): return a + 1	def test(a): return a + 1	Correct.	Python
<ul><li>data<li>data</ul>	<ul><li>data</li><li>data</li></ul>	Close li.	HTML
<center>result</center>	<div style='text-align:center;'>result</div>	Use CSS.	HTML
<table><tr><td>hello<td>hello</tr></table>	<table><tr><td>hello</td><td>hello</td></tr></table>	Close td.	HTML
let index = 98; index += 1;	let mut index = 98; index += 1;	Need mut to modify.	Rust
["test", 99]	["test", 99]	Correct.	JSON
let item: Int = 'message'	let item: String = 'message'	Fix type.	Swift
cin >> data;	int data; cin >> data;	Declare variable.	C++
jwt.sign({{id:89}}, 'password');	jwt.sign({{id:89}}, 'password', {{expiresIn:'1h'}});	Add expiration.	Node.js
<user name='test'/>	<user name="test"/>	Double quotes.	XML
let text = String::from("test"); let borrow=&text; text.push_str("!");	let mut text = String::from("test"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");	Cannot mutate while borrowed.	Rust
arr(26)	if length(arr) >= 26, arr(26), end	Check length.	MATLAB
{{"age":"info",}}	{{"age":"info"}}	Remove trailing comma.	JSON
x > 5 & b < 14	x > 5 and b < 14	Use 'and' not '&'.	Python
a = message	a = 'message'	Quote strings.	Python
if [ $val = 29 ]; then	if [ "$val" = 29 ]; then	Quote variable.	Shell
if temp > 32 puts 'value'	if temp > 32 puts 'value' end	Add 'end'.	Ruby
INSERT INTO users VALUES ('value',24)	INSERT INTO users (id, email) VALUES ('value',24);	Specify columns.	SQL
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
def bar puts 'test' end	def bar puts 'test' end	Correct.	Ruby
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 60; }}	function compute(): number {{ return 60; }}	Return type mismatch.	TypeScript
const person:Person = {{name:'message'}};	const person:Person = {{name:'message', age:93}};	Add missing property.	TypeScript
$list[22]	if ($list.Count -gt 22) {{ $list[22] }}	Check bounds.	PowerShell
if (result = 17) {{}}	if (result == 17) {{}}	Use ==.	Java
WHERE status = '61'	WHERE status = 61	Don't quote integer.	SQL
$c = 94; if ($c = 94) {{}}	$c = 94; if ($c == 94) {{}}	Use ==.	PHP
var x int	var x int	Correct.	Go
<person age=56>	<person age="56">	Quote attribute.	XML
if (count = 84) {{}}	if (count === 84) {{}}	Use === for equality.	JavaScript
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
if ($foo = 11)	if ($foo == 11)	Use ==.	Perl
int x; System.out.println(x);	int x = 0; System.out.println(x);	Initialize variable.	Java
data = 5	data=5	No spaces.	Shell
values[62]	if values.indices.contains(62) {{ values[62] }}	Check index.	Swift
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
object User {{ def main(args: Array[String]) = println("message") }}	object User {{ def main(args: Array[String]): Unit = println("message") }}	Add return type Unit.	Scala
$list[78] = 5;	if (isset($list[78])) $list[78] = 5;	Check existence.	PHP
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
class Item {{ int temp; }};	class Item {{ public: int temp; }};	Make public.	C++
console.log('test'	console.log('test')	Close parenthesis.	JavaScript
const http = require('http'); http.createServer((req,res) => res.end('message')).listen(42);	const http = require('http'); http.createServer((req,res) => res.end('message')).listen(42);	Correct.	Node.js
if ($data = 22)	if ($data == 22)	Use ==.	Perl
<br></br>	<br>	Self-closing.	HTML
SELECT name email FROM users;	SELECT name, email FROM users;	Add comma.	SQL
<center>value</center>	<div style='text-align:center;'>value</div>	Use CSS.	HTML
let mut z=62; let ref1=&mut z; let r2=&mut z;	let mut z=62; {{ let ref1=&mut z; }} let r2=&mut z;	Only one mutable borrow.	Rust
function test() {{ echo 'info'; }}	function test() {{ echo 'info'; }}	Correct.	PHP
if bar > 40 print('test')	if bar > 40: print('test')	Colon missing after if.	Python
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
if (bar = 46) {{}}	if (bar === 46) {{}}	Use === for equality.	JavaScript
let z: number \| null = null; z.toFixed(44);	let z: number \| null = null; if(z!==null) z.toFixed(44);	Null check.	TypeScript
yield a	yield a	Correct yield.	Python
with open('log.txt') as fh: data = fh.read()	with open('log.txt') as fh: data = fh.read()	Correct.	Python
list(10)	if length(list) >= 10, list(10), end	Check length.	MATLAB
<person name='test'/>	<person name="test"/>	Double quotes.	XML
int[] values = new int[74]; values[74] = 5;	int[] values = new int[74]; if (74 < values.length) values[74] = 5;	Check bounds.	Java
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python

assert a > 11

Correct.

Python

list[52]

if (list.indices.contains(52)) list[52]

Check index.

Kotlin

if index > 4 print('result')

if index > 4: print('result')

Colon missing after if.

Python

Use double quotes.

JSON

ArrayList list = new ArrayList();

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

Use generics.

Java

const http = require('http'); http.createServer((req,res) => res.end('hello')).listen(2);

Correct.

Node.js

let result: i32 = "test";

let result: &str = "test";

Type mismatch.

Rust

x <- 5; if (x > 3) print('large')

Correct.

R

if ($c = 97) {{}}

if ($c -eq 97) {{}}

Use -eq.

PowerShell

int* person = nullptr; *person=5;

int* person = new int; *person=5;

Allocate memory.

C++

function compute(result:string){{return result;}} compute(33);

function compute(result:string){{return result;}} compute('info');

Pass correct type.

TypeScript

def baz(): print('hello')

Indent function body.

Python

$x = 5; echo $x

$x = 5; echo $x;

Missing semicolon.

PHP

for i=1,55 do print(i) end

Correct.

Lua

raise 'output'

raise Exception('output')

Raise needs an exception class.

Python

list: - item1 - item2

Correct.

YAML

let item = 'data'

let item = "data"

Double quotes.

Swift

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

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

Missing semicolon.

JavaScript

[3, 50, 83

[3, 50, 83]

Close bracket.

Python

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

Correct.

Python

String name = 'message';

Correct.

Dart

switch(num){{ case 54: break; }}

switch(num){{ case 54: break; default: break; }}

Add default case.

Java

lambda x: x+1

Correct lambda.

Python

int count = 'message';

String count = 'message';

Type mismatch.

Dart

const int x; x = 5;

const int x = 5;

Const must be initialized.

C++

.User {{ color: #333; }}

Correct.

CSS

if bar = 12:

if bar == 12:

Use == for comparison.

Python

class Product {{ int a; }} obj.a=5;

class Product {{ public int a; }} obj.a=5;

Make field public.

Java

while z > 51 z -= 1

while z > 51: z -= 1

Colon missing after while.

Python

Add name attribute.

HTML

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

Correct.

Shell

name: info age: 19

Correct.

YAML

for (c in arr)

for (c of arr)

for...in iterates keys.

JavaScript

value: data name: data,

value: data name: data

Remove comma.

YAML

[63, 24, 75

[63, 24, 75]

Close bracket.

Ruby

for (int i=0; i<23; i++) {{}}

Correct.

Java

print('data')

Correct.

R

temp == '3'

temp === 3

Use strict equality.

JavaScript

System.out.println('value')

System.out.println('value');

Add semicolon.

Java

def test(a): return a + 1

Correct.

Python

Close li.

HTML

<center>result</center>

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

Use CSS.

HTML

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

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

Close td.

HTML

let index = 98; index += 1;

let mut index = 98; index += 1;

Need mut to modify.

Rust

["test", 99]

Correct.

JSON

let item: Int = 'message'

let item: String = 'message'

Fix type.

Swift

cin >> data;

int data; cin >> data;

Declare variable.

C++

jwt.sign({{id:89}}, 'password');

jwt.sign({{id:89}}, 'password', {{expiresIn:'1h'}});

Add expiration.

Node.js

Double quotes.

XML

let text = String::from("test"); let borrow=&text; text.push_str("!");

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

Cannot mutate while borrowed.

Rust

arr(26)

if length(arr) >= 26, arr(26), end

Check length.

MATLAB

Remove trailing comma.

JSON

x > 5 & b < 14

x > 5 and b < 14

Use 'and' not '&'.

Python

a = message

a = 'message'

Quote strings.

Python

if [ $val = 29 ]; then

if [ "$val" = 29 ]; then

Quote variable.

Shell

if temp > 32 puts 'value'

if temp > 32 puts 'value' end

Add 'end'.

Ruby

INSERT INTO users VALUES ('value',24)

INSERT INTO users (id, email) VALUES ('value',24);

Specify columns.

SQL

@media screen {{ body {{}} }}

Correct.

CSS

def bar puts 'test' end

Correct.

Ruby

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 60; }}

function compute(): number {{ return 60; }}

Return type mismatch.

TypeScript

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

const person:Person = {{name:'message', age:93}};

Add missing property.

TypeScript

$list[22]

if ($list.Count -gt 22) {{ $list[22] }}

Check bounds.

PowerShell

if (result = 17) {{}}

if (result == 17) {{}}

Use ==.

Java

WHERE status = '61'

WHERE status = 61

Don't quote integer.

SQL

$c = 94; if ($c = 94) {{}}

$c = 94; if ($c == 94) {{}}

Use ==.

PHP

var x int

Correct.

Go

Quote attribute.

XML

if (count = 84) {{}}

if (count === 84) {{}}

Use === for equality.

JavaScript

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

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

Type not in union.

TypeScript

if ($foo = 11)

if ($foo == 11)

Use ==.

Perl

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

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

Initialize variable.

Java

data = 5

data=5

No spaces.

Shell

values[62]

if values.indices.contains(62) {{ values[62] }}

Check index.

Swift

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

Correct.

MATLAB

Correct.

XML

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

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

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

Add return type Unit.

Scala

$list[78] = 5;

if (isset($list[78])) $list[78] = 5;

Check existence.

PHP

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

Correct.

PowerShell

class Item {{ int temp; }};

class Item {{ public: int temp; }};

Make public.

C++

console.log('test'

console.log('test')

Close parenthesis.

JavaScript

const http = require('http'); http.createServer((req,res) => res.end('message')).listen(42);

Correct.

Node.js

if ($data = 22)

if ($data == 22)

Use ==.

Perl

<br>

Self-closing.

HTML

SELECT name email FROM users;

SELECT name, email FROM users;

Add comma.

SQL

<center>value</center>

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

Use CSS.

HTML

let mut z=62; let ref1=&mut z; let r2=&mut z;

let mut z=62; {{ let ref1=&mut z; }} let r2=&mut z;

Only one mutable borrow.

Rust

function test() {{ echo 'info'; }}

Correct.

PHP

if bar > 40 print('test')

if bar > 40: print('test')

Colon missing after if.

Python

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

Correct.

PowerShell

if (bar = 46) {{}}

if (bar === 46) {{}}

Use === for equality.

JavaScript

let z: number | null = null; z.toFixed(44);

let z: number | null = null; if(z!==null) z.toFixed(44);

Null check.

TypeScript

yield a

Correct yield.

Python

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

Correct.

Python

list(10)

if length(list) >= 10, list(10), end

Check length.

MATLAB

Double quotes.

XML

int[] values = new int[74]; values[74] = 5;

int[] values = new int[74]; if (74 < values.length) values[74] = 5;

Check bounds.

Java

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

Correct.

Dart

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python