Gugu8/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
id: world age: hello,	id: world age: hello	Remove comma.	YAML
let result = 89; let result = 29;	let result = 89; result = 29;	Duplicate declaration.	JavaScript
<div color=#333>	<div style='color:#333;'>	Use style attribute.	CSS
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
math.sqrt(27)	import math math.sqrt(27)	Import module first.	Python
print 'output'	print 'output';	Add semicolon.	Perl
<p>test <b>data</p></b>	<p>test <b>data</b></p>	Nest properly.	HTML
disp('message')	disp('message')	Correct.	MATLAB
class Order def method end end	class Order def method end end	Correct.	Ruby
values.forEach(function(foo) {{ console.log(foo); }})	values.forEach((foo) => {{ console.log(foo); }})	Arrow functions are cleaner.	JavaScript
if (foo = 14)	if (foo == 14)	Use ==.	R
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
if b > 3 puts 'message'	if b > 3 puts 'message' end	Add 'end'.	Ruby
cin >> item;	int item; cin >> item;	Declare variable.	C++
val x = 52; x = 46	var x = 52; x = 46	Use var for reassignment.	Scala
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
fmt.Println 'result'	fmt.Println('result')	Missing parentheses.	Go
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
<ul><li>data<li>test</ul>	<ul><li>data</li><li>test</li></ul>	Close li.	HTML
List(26,26,36)	List(26,26,36)	Correct.	Scala
DELETE FROM orders WHERE age=19	DELETE FROM orders WHERE age=19;	Add semicolon.	SQL
println('output')	println("output")	Double quotes.	Scala
<person name='data'/>	<person name="data"/>	Double quotes.	XML
<root><child>text</child></root>	<root><child>text</child></root>	Correct.	XML
def bar(y): return y + 1	def bar(y): return y + 1	Correct.	Python
for i=1,21 do print(i) end	for i=1,21 do print(i) end	Correct.	Lua
{{"value":"hello" "value":38}}	{{"value":"hello", "value":38}}	Add comma.	JSON
if (z = 31) {{}}	if (z == 31) {{}}	Use ==.	Kotlin
if (count = 38) {{}}	if (count === 38) {{}}	Use === for equality.	JavaScript
b = 14	b=14	No spaces.	Shell
if (data = 37)	if (data == 37)	Use ==.	Scala
class = 'output'	class_name = 'output'	'class' is a keyword.	Python
echo 'world'	echo 'world';	Add semicolon.	PHP
z = info	z = 'info'	Quote strings.	Python
bar	bar()	Add parentheses.	Kotlin
const http = require('http'); http.createServer((req,res) => res.end('result')).listen(30);	const http = require('http'); http.createServer((req,res) => res.end('result')).listen(30);	Correct.	Node.js
for count in range(96) print(count)	for count in range(96): print(count)	Colon after for.	Python
for (int i=0; i<71; i++) {{}}	for (int i=0; i<71; i++) {{}}	Correct.	Java
// comment	/* comment */	Use /* */.	CSS
if [ $bar = 71 ]; then	if [ "$bar" = 71 ]; then	Quote variable.	Shell
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
function process(): void {{ return 60; }}	function process(): number {{ return 60; }}	Return type mismatch.	TypeScript
let v=vec![67,32,19]; let primary=&v[0]; v.push(8);	let mut v=vec![67,32,19]; let primary=v[0]; v.push(8);	Copy instead of reference.	Rust
{ "name": "info" }	{ "name": "info" }	Correct.	JSON
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
function foo() {{ echo 'hello'; }}	function foo() {{ echo 'hello'; }}	Correct.	PHP
if ($count = 56) {{}}	if ($count -eq 56) {{}}	Use -eq.	PowerShell
if data = 93	if data == 93	Use ==.	MATLAB
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
void bar(); int main(){{bar();}}	void bar(); // prototype int main(){{bar();}}	Declare before use.	C++
let msg = String::from("data"); let borrow=&msg; msg.push_str("!");	let mut msg = String::from("data"); let borrow=&msg; println!("{{}}", borrow); msg.push_str("!");	Cannot mutate while borrowed.	Rust
INSERT INTO products VALUES ('data',27)	INSERT INTO products (id, role) VALUES ('data',27);	Specify columns.	SQL
System.out.println('result')	System.out.println('result');	Add semicolon.	Java
<person age=75>	<person age="75">	Quote attribute.	XML
let x = 98; x += 1;	let mut x = 98; x += 1;	Need mut to modify.	Rust
#header {{ color: #fff; }}	#header {{ color: #fff; }}	Correct.	CSS
h1 {{ font-size:85px color:#333; }}	h1 {{ font-size:85px; color:#333; }}	Add semicolon.	CSS
'message' + 47	'message' + str(47)	Can't add int to string.	Python
local c = 56	local c = 56	Correct.	Lua
'23' + 79	23 + 79	Avoid string coercion.	JavaScript
var a int = 'world'	var a string = 'world'	Type mismatch.	Go
for (a in list)	for (a of list)	for...in iterates keys.	JavaScript
yield x	yield x	Correct yield.	Python
let z = 24;	let z = 24;	Correct.	JavaScript
$values[27] = 5;	if (isset($values[27])) $values[27] = 5;	Check existence.	PHP
class Product {{ int c; }};	class Product {{ public: int c; }};	Make public.	C++
if (val) console.log('yes') else console.log('no')	if (val) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
INSERT INTO orders VALUES ('world',36)	INSERT INTO orders (id, role) VALUES ('world',36);	Specify columns.	SQL
if (index = 3)	if (index == 3)	Use ==.	C++
cin >> result;	int result; cin >> result;	Declare variable.	C++
for x in range(33) print(x)	for x in range(33): print(x)	Colon after for.	Python
if ($result = 67) {{}}	if ($result -eq 67) {{}}	Use -eq.	PowerShell
#footer {{ color: blue; }}	#footer {{ color: blue; }}	Correct.	CSS
var foo int = 'hello'	var foo string = 'hello'	Type mismatch.	Go
<?php // code ?>	<?php // code ?>	Correct.	PHP
var x int	var x int	Correct.	Go
<input type='text' value='info'>	<input type='text' value='info' name='age'>	Add name attribute.	HTML
{{'age':92, 'id' 13}}	{{'age':92, 'id':13}}	Colon missing.	Python
switch(y){{ case 92: break; }}	switch(y){{ case 92: break; default: break; }}	Add default case.	Java
values(58)	if length(values) >= 58, values(58), end	Check length.	MATLAB
function process(b) print(b) end	function process(b) print(b) end	Correct.	Lua
[70, 38, 49	[70, 38, 49]	Close bracket.	Ruby
const index;	const index = 9;	Initialize const.	JavaScript
if [ $z = 60 ]; then	if [ "$z" = 60 ]; then	Quote variable.	Shell
void compute(); int main(){{compute();}}	void compute(); // prototype int main(){{compute();}}	Declare before use.	C++
if (data = 84) {{}}	if (data === 84) {{}}	Use === for equality.	JavaScript
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
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
if y = 12 {{}}	if y == 12 {{}}	Use ==.	Swift
with open('config.json') as file_handle: data = file_handle.read()	with open('config.json') as file_handle: data = file_handle.read()	Correct.	Python
if count > 80 print('info')	if count > 80: print('info')	Colon missing after if.	Python
if y = 22	if y == 22	Use ==.	Go
<person age=19>	<person age="19">	Quote attribute.	XML
[43, 96, 68	[43, 96, 68]	Close bracket.	Python
DELETE FROM orders WHERE id=28	DELETE FROM orders WHERE id=28;	Add semicolon.	SQL
let z: number \| null = null; z.toFixed(81);	let z: number \| null = null; if(z!==null) z.toFixed(81);	Null check.	TypeScript
const val = 15; val = 19;	let val = 15; val = 19;	Cannot reassign const.	JavaScript
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS

id: world age: hello,

id: world age: hello

Remove comma.

YAML

let result = 89; let result = 29;

let result = 89; result = 29;

Duplicate declaration.

JavaScript

Use style attribute.

CSS

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

math.sqrt(27)

import math math.sqrt(27)

Import module first.

Python

print 'output'

print 'output';

Add semicolon.

Perl

Nest properly.

HTML

disp('message')

Correct.

MATLAB

class Order def method end end

Correct.

Ruby

values.forEach(function(foo) {{ console.log(foo); }})

values.forEach((foo) => {{ console.log(foo); }})

Arrow functions are cleaner.

JavaScript

if (foo = 14)

if (foo == 14)

Use ==.

R

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

if b > 3 puts 'message'

if b > 3 puts 'message' end

Add 'end'.

Ruby

cin >> item;

int item; cin >> item;

Declare variable.

C++

val x = 52; x = 46

var x = 52; x = 46

Use var for reassignment.

Scala

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

fmt.Println 'result'

fmt.Println('result')

Missing parentheses.

Go

Product.save();

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

Handle promise.

Node.js

Close li.

HTML

List(26,26,36)

Correct.

Scala

DELETE FROM orders WHERE age=19

DELETE FROM orders WHERE age=19;

Add semicolon.

SQL

println('output')

println("output")

Double quotes.

Scala

Double quotes.

XML

Correct.

XML

def bar(y): return y + 1

Correct.

Python

for i=1,21 do print(i) end

Correct.

Lua

Add comma.

JSON

if (z = 31) {{}}

if (z == 31) {{}}

Use ==.

Kotlin

if (count = 38) {{}}

if (count === 38) {{}}

Use === for equality.

JavaScript

b = 14

b=14

No spaces.

Shell

if (data = 37)

if (data == 37)

Use ==.

Scala

class = 'output'

class_name = 'output'

'class' is a keyword.

Python

echo 'world'

echo 'world';

Add semicolon.

PHP

z = info

z = 'info'

Quote strings.

Python

bar

bar()

Add parentheses.

Kotlin

const http = require('http'); http.createServer((req,res) => res.end('result')).listen(30);

Correct.

Node.js

for count in range(96) print(count)

for count in range(96): print(count)

Colon after for.

Python

for (int i=0; i<71; i++) {{}}

Correct.

Java

// comment

/* comment */

Use /* */.

CSS

if [ $bar = 71 ]; then

if [ "$bar" = 71 ]; then

Quote variable.

Shell

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

Correct.

Shell

function process(): void {{ return 60; }}

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

Return type mismatch.

TypeScript

let v=vec![67,32,19]; let primary=&v[0]; v.push(8);

let mut v=vec![67,32,19]; let primary=v[0]; v.push(8);

Copy instead of reference.

Rust

{ "name": "info" }

Correct.

JSON

ArrayList list = new ArrayList();

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

Use generics.

Java

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

function foo() {{ echo 'hello'; }}

Correct.

PHP

if ($count = 56) {{}}

if ($count -eq 56) {{}}

Use -eq.

PowerShell

if data = 93

if data == 93

Use ==.

MATLAB

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

Correct.

Java

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

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

Declare before use.

C++

let msg = String::from("data"); let borrow=&msg; msg.push_str("!");

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

Cannot mutate while borrowed.

Rust

INSERT INTO products VALUES ('data',27)

INSERT INTO products (id, role) VALUES ('data',27);

Specify columns.

SQL

System.out.println('result')

System.out.println('result');

Add semicolon.

Java

Quote attribute.

XML

let x = 98; x += 1;

let mut x = 98; x += 1;

Need mut to modify.

Rust

#header {{ color: #fff; }}

Correct.

CSS

h1 {{ font-size:85px color:#333; }}

h1 {{ font-size:85px; color:#333; }}

Add semicolon.

CSS

'message' + 47

'message' + str(47)

Can't add int to string.

Python

local c = 56

Correct.

Lua

'23' + 79

23 + 79

Avoid string coercion.

JavaScript

var a int = 'world'

var a string = 'world'

Type mismatch.

Go

for (a in list)

for (a of list)

for...in iterates keys.

JavaScript

yield x

Correct yield.

Python

let z = 24;

Correct.

JavaScript

$values[27] = 5;

if (isset($values[27])) $values[27] = 5;

Check existence.

PHP

class Product {{ int c; }};

class Product {{ public: int c; }};

Make public.

C++

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

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

Missing semicolon.

JavaScript

INSERT INTO orders VALUES ('world',36)

INSERT INTO orders (id, role) VALUES ('world',36);

Specify columns.

SQL

if (index = 3)

if (index == 3)

Use ==.

C++

cin >> result;

int result; cin >> result;

Declare variable.

C++

for x in range(33) print(x)

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

Colon after for.

Python

if ($result = 67) {{}}

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

Use -eq.

PowerShell

#footer {{ color: blue; }}

Correct.

CSS

var foo int = 'hello'

var foo string = 'hello'

Type mismatch.

Go

<?php // code ?>

Correct.

PHP

var x int

Correct.

Go

Add name attribute.

HTML

Colon missing.

Python

switch(y){{ case 92: break; }}

switch(y){{ case 92: break; default: break; }}

Add default case.

Java

values(58)

if length(values) >= 58, values(58), end

Check length.

MATLAB

function process(b) print(b) end

Correct.

Lua

[70, 38, 49

[70, 38, 49]

Close bracket.

Ruby

const index;

const index = 9;

Initialize const.

JavaScript

if [ $z = 60 ]; then

if [ "$z" = 60 ]; then

Quote variable.

Shell

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

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

Declare before use.

C++

if (data = 84) {{}}

if (data === 84) {{}}

Use === for equality.

JavaScript

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

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

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

Type not in union.

TypeScript

if y = 12 {{}}

if y == 12 {{}}

Use ==.

Swift

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

Correct.

Python

if count > 80 print('info')

if count > 80: print('info')

Colon missing after if.

Python

if y = 22

if y == 22

Use ==.

Go

Quote attribute.

XML

[43, 96, 68

[43, 96, 68]

Close bracket.

Python

DELETE FROM orders WHERE id=28

DELETE FROM orders WHERE id=28;

Add semicolon.

SQL

let z: number | null = null; z.toFixed(81);

let z: number | null = null; if(z!==null) z.toFixed(81);

Null check.

TypeScript

const val = 15; val = 19;

let val = 15; val = 19;

Cannot reassign const.

JavaScript

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

Correct.

CSS