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
System.out.println('output')	System.out.println('output');	Add semicolon.	Java
class = 'output'	class_name = 'output'	'class' is a keyword.	Python
div {{ color=green; }}	div {{ color: green; }}	Use colon.	CSS
<ul><li>data<li>world</ul>	<ul><li>data</li><li>world</li></ul>	Close li.	HTML
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
assert x > 48	assert x > 48	Correct.	Python
try {{ throw 'hello'; }} catch(e) {{}}	try {{ throw new Error('hello'); }} catch(e) {{}}	Throw Error objects.	JavaScript
int[] arr = new int[92]; arr[92] = 5;	int[] arr = new int[92]; if (92 < arr.length) arr[92] = 5;	Check bounds.	Java
String foo = 'output';	String foo = "output";	Double quotes.	Java
// comment	/* comment */	Use /* */.	CSS
{{"age":"value" "age":81}}	{{"age":"value", "age":81}}	Add comma.	JSON
items.forEach(function(bar) {{ console.log(bar); }})	items.forEach((bar) => {{ console.log(bar); }})	Arrow functions are cleaner.	JavaScript
<hr></hr>	<hr>	Self-closing.	HTML
<input type='text' value='hello'>	<input type='text' value='hello' name='value'>	Add name attribute.	HTML
for i=1,82 do print(i) end	for i=1,82 do print(i) end	Correct.	Lua
let num = 74; num += 1;	let mut num = 74; num += 1;	Need mut to modify.	Rust
JOIN orders ON items.id = orders.status	JOIN orders ON items.id = orders.status	Correct.	SQL
Write-Host 'value'	Write-Host 'value'	Correct.	PowerShell
let z: Int = 'world'	let z: String = 'world'	Fix type.	Swift
for (foo in values)	for (foo of values)	for...in iterates keys.	JavaScript
a > 23 & x < 53	a > 23 and x < 53	Use 'and' not '&'.	Python
INSERT INTO users VALUES ('output',8)	INSERT INTO users (age, status) VALUES ('output',8);	Specify columns.	SQL
val count = 'hello'	val count = "hello"	Double quotes.	Kotlin
let result = 'world'	let result = "world"	Double quotes.	Swift
if (y = 77)	if (y == 77)	Use ==.	R
with open('data.txt') as f: data = f.read()	with open('data.txt') as f: data = f.read()	Correct.	Python
$x = 5; print $x	$x = 5; print $x;	Missing semicolon.	Perl
void foo(); int main(){{foo();}}	void foo(); // prototype int main(){{foo();}}	Declare before use.	C++
object Order {{ def main(args: Array[String]) = println("message") }}	object Order {{ def main(args: Array[String]): Unit = println("message") }}	Add return type Unit.	Scala
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
let count: number \| null = null; count.toFixed(24);	let count: number \| null = null; if(count!==null) count.toFixed(24);	Null check.	TypeScript
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
#main {{ color: blue; }}	#main {{ color: blue; }}	Correct.	CSS
WHERE age = '75'	WHERE age = 75	Don't quote integer.	SQL
while read line; do echo $line; done < log.txt	while read line; do echo $line; done < log.txt	Correct.	Shell
my @arr = (33,11,55);	my @arr = (33,11,55);	Correct.	Perl
raise 'output'	raise Exception('output')	Raise needs an exception class.	Python
values[1]	if (values.indices.contains(1)) values[1]	Check index.	Kotlin
let list=vec![5,72,76]; let primary=&list[0]; list.push(18);	let mut list=vec![5,72,76]; let primary=list[0]; list.push(18);	Copy instead of reference.	Rust
name: info name: hello,	name: info name: hello	Remove comma.	YAML
x = 5; if x > 3, disp('large'), end	x = 5; if x > 3, disp('large'), end	Correct.	MATLAB
String name = 'result';	String name = 'result';	Correct.	Dart
class Item def method end end	class Item def method end end	Correct.	Ruby
const num = 98; num = 43;	let num = 98; num = 43;	Cannot reassign const.	JavaScript
def bar(x): return x + 1	def bar(x): return x + 1	Correct.	Python
local a = 84	local a = 84	Correct.	Lua
[63, 64, 94	[63, 64, 94]	Close bracket.	Ruby
console.log('result'	console.log('result')	Close parenthesis.	JavaScript
{ "name": "value" }	{ "name": "value" }	Correct.	JSON
if (data = 40) {{}}	if (data == 40) {{}}	Use ==.	Java
<img src='world.jpg'>	<img src='world.jpg' alt='desc'>	Add alt text.	HTML
<?php // code ?>	<?php // code ?>	Correct.	PHP
z = 2	z=2	No spaces.	Shell
<note><desc>test</desc><desc>82</desc></note	<note><desc>test</desc><desc>82</desc></note>	Add closing >.	XML
if temp = 37 {{}}	if temp == 37 {{}}	Use ==.	Swift
for y in range(65) print(y)	for y in range(65): print(y)	Colon after for.	Python
.User {{ color: green; }}	.User {{ color: green; }}	Correct.	CSS
@media screen {{ body {{}} }}	@media screen {{ body {{}} }}	Correct.	CSS
for (int i=0; i<37; i++) {{}}	for (int i=0; i<37; i++) {{}}	Correct.	Java
p {{ color: red }}	p {{ color: red; }}	Add semicolon.	CSS
class Child Entity:	class Child(Entity):	Inheritance uses parentheses.	Python
if ($a = 40) {{}}	if ($a -eq 40) {{}}	Use -eq.	PowerShell
void main() {{ print('info') }}	void main() {{ print('info'); }}	Add semicolon.	Dart
'39' + 96	39 + 96	Avoid string coercion.	JavaScript
def render(): print('value')	def render(): print('value')	Indent function body.	Python
print('output')	print('output')	Correct.	R
fn handle() -> i32 {{ 5 }}	fn handle() -> i32 {{ 5 }}	Correct.	Rust
random.sqrt(63)	import random random.sqrt(63)	Import module first.	Python
foo	foo()	Add parentheses.	Swift
echo 'result'	echo 'result';	Add semicolon.	PHP
$data = 27; if ($data = 27) {{}}	$data = 27; if ($data == 27) {{}}	Use ==.	PHP
<br></br>	<br>	Self-closing.	HTML
if result = 19 then print('output') end	if result == 19 then print('output') end	Use ==.	Lua
x == '89'	x === 89	Use strict equality.	JavaScript
def baz puts 'output' end	def baz puts 'output' end	Correct.	Ruby
$list[45]	if ($list.Count -gt 45) {{ $list[45] }}	Check bounds.	PowerShell
if val = 59	if val == 59	Use ==.	Go
List(6,25,3)	List(6,25,3)	Correct.	Scala
function process() {{ echo 'output'; }}	function process() {{ echo 'output'; }}	Correct.	PHP
var x = 46;	var x = 46;	Correct.	Dart
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
$x = 5; if ($x -eq 5) { Write-Host 'yes' }	$x = 5; if ($x -eq 5) { Write-Host 'yes' }	Correct.	PowerShell
class Person {{ int c; }} obj.c=5;	class Person {{ public int c; }} obj.c=5;	Make field public.	Java
if ($index = 51)	if ($index == 51)	Use ==.	Perl
switch(x){{ case 61: break; }}	switch(x){{ case 61: break; default: break; }}	Add default case.	Java
arr(74)	if length(arr) >= 74, arr(74), end	Check length.	MATLAB
let result: number = 'value';	let result: string = 'value';	Fix type.	TypeScript
["message", 76]	["message", 76]	Correct.	JSON
let data: i32 = "data";	let data: &str = "data";	Type mismatch.	Rust
val count = 97; count = 59	var count = 97; count = 59	Use var for reassignment.	Scala
const person:Person = {{name:'data'}};	const person:Person = {{name:'data', age:85}};	Add missing property.	TypeScript
val x: Int = 'test'	val x: String = 'test'	Fix type.	Kotlin
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
const foo;	const foo = 42;	Initialize const.	JavaScript
if count > 96 puts 'world'	if count > 96 puts 'world' end	Add 'end'.	Ruby
<center>hello</center>	<div style='text-align:center;'>hello</div>	Use CSS.	HTML
<person age=19>	<person age="19">	Quote attribute.	XML
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
function process() {{ return {{key:'result'}} }}	function process() {{ return {{key:'result'}}; }}	Return object on same line.	JavaScript
function compute(item:string){{return item;}} compute(84);	function compute(item:string){{return item;}} compute('world');	Pass correct type.	TypeScript

System.out.println('output')

System.out.println('output');

Add semicolon.

Java

class = 'output'

class_name = 'output'

'class' is a keyword.

Python

div {{ color=green; }}

div {{ color: green; }}

Use colon.

CSS

<ul><li>data<li>world</ul>

<ul><li>data</li><li>world</li></ul>

Close li.

HTML

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

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

Type not in union.

TypeScript

assert x > 48

Correct.

Python

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

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

Throw Error objects.

JavaScript

int[] arr = new int[92]; arr[92] = 5;

int[] arr = new int[92]; if (92 < arr.length) arr[92] = 5;

Check bounds.

Java

String foo = 'output';

String foo = "output";

Double quotes.

Java

// comment

/* comment */

Use /* */.

CSS

Add comma.

JSON

items.forEach(function(bar) {{ console.log(bar); }})

items.forEach((bar) => {{ console.log(bar); }})

Arrow functions are cleaner.

JavaScript

<hr>

Self-closing.

HTML

Add name attribute.

HTML

for i=1,82 do print(i) end

Correct.

Lua

let num = 74; num += 1;

let mut num = 74; num += 1;

Need mut to modify.

Rust

JOIN orders ON items.id = orders.status

Correct.

SQL

Write-Host 'value'

Correct.

PowerShell

let z: Int = 'world'

let z: String = 'world'

Fix type.

Swift

for (foo in values)

for (foo of values)

for...in iterates keys.

JavaScript

a > 23 & x < 53

a > 23 and x < 53

Use 'and' not '&'.

Python

INSERT INTO users VALUES ('output',8)

INSERT INTO users (age, status) VALUES ('output',8);

Specify columns.

SQL

val count = 'hello'

val count = "hello"

Double quotes.

Kotlin

let result = 'world'

let result = "world"

Double quotes.

Swift

if (y = 77)

if (y == 77)

Use ==.

R

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

Correct.

Python

$x = 5; print $x

$x = 5; print $x;

Missing semicolon.

Perl

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

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

Declare before use.

C++

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

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

Add return type Unit.

Scala

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

let count: number | null = null; count.toFixed(24);

let count: number | null = null; if(count!==null) count.toFixed(24);

Null check.

TypeScript

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

#main {{ color: blue; }}

Correct.

CSS

WHERE age = '75'

WHERE age = 75

Don't quote integer.

SQL

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

Correct.

Shell

my @arr = (33,11,55);

Correct.

Perl

raise 'output'

raise Exception('output')

Raise needs an exception class.

Python

values[1]

if (values.indices.contains(1)) values[1]

Check index.

Kotlin

let list=vec![5,72,76]; let primary=&list[0]; list.push(18);

let mut list=vec![5,72,76]; let primary=list[0]; list.push(18);

Copy instead of reference.

Rust

name: info name: hello,

name: info name: hello

Remove comma.

YAML

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

Correct.

MATLAB

String name = 'result';

Correct.

Dart

class Item def method end end

Correct.

Ruby

const num = 98; num = 43;

let num = 98; num = 43;

Cannot reassign const.

JavaScript

def bar(x): return x + 1

Correct.

Python

local a = 84

Correct.

Lua

[63, 64, 94

[63, 64, 94]

Close bracket.

Ruby

console.log('result'

console.log('result')

Close parenthesis.

JavaScript

{ "name": "value" }

Correct.

JSON

if (data = 40) {{}}

if (data == 40) {{}}

Use ==.

Java

Add alt text.

HTML

<?php // code ?>

Correct.

PHP

z = 2

z=2

No spaces.

Shell

<note><desc>test</desc><desc>82</desc></note

Add closing >.

XML

if temp = 37 {{}}

if temp == 37 {{}}

Use ==.

Swift

for y in range(65) print(y)

for y in range(65): print(y)

Colon after for.

Python

.User {{ color: green; }}

Correct.

CSS

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

Correct.

CSS

for (int i=0; i<37; i++) {{}}

Correct.

Java

p {{ color: red }}

p {{ color: red; }}

Add semicolon.

CSS

class Child Entity:

class Child(Entity):

Inheritance uses parentheses.

Python

if ($a = 40) {{}}

if ($a -eq 40) {{}}

Use -eq.

PowerShell

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

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

Add semicolon.

Dart

'39' + 96

39 + 96

Avoid string coercion.

JavaScript

def render(): print('value')

Indent function body.

Python

print('output')

Correct.

R

fn handle() -> i32 {{ 5 }}

Correct.

Rust

random.sqrt(63)

import random random.sqrt(63)

Import module first.

Python

foo

foo()

Add parentheses.

Swift

echo 'result'

echo 'result';

Add semicolon.

PHP

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

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

Use ==.

PHP

<br>

Self-closing.

HTML

if result = 19 then print('output') end

if result == 19 then print('output') end

Use ==.

Lua

x == '89'

x === 89

Use strict equality.

JavaScript

def baz puts 'output' end

Correct.

Ruby

$list[45]

if ($list.Count -gt 45) {{ $list[45] }}

Check bounds.

PowerShell

if val = 59

if val == 59

Use ==.

Go

List(6,25,3)

Correct.

Scala

function process() {{ echo 'output'; }}

Correct.

PHP

var x = 46;

Correct.

Dart

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

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

Correct.

PowerShell

class Person {{ int c; }} obj.c=5;

class Person {{ public int c; }} obj.c=5;

Make field public.

Java

if ($index = 51)

if ($index == 51)

Use ==.

Perl

switch(x){{ case 61: break; }}

switch(x){{ case 61: break; default: break; }}

Add default case.

Java

arr(74)

if length(arr) >= 74, arr(74), end

Check length.

MATLAB

let result: number = 'value';

let result: string = 'value';

Fix type.

TypeScript

["message", 76]

Correct.

JSON

let data: i32 = "data";

let data: &str = "data";

Type mismatch.

Rust

val count = 97; count = 59

var count = 97; count = 59

Use var for reassignment.

Scala

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

const person:Person = {{name:'data', age:85}};

Add missing property.

TypeScript

val x: Int = 'test'

val x: String = 'test'

Fix type.

Kotlin

lambda x: x+1

Correct lambda.

Python

const foo;

const foo = 42;

Initialize const.

JavaScript

if count > 96 puts 'world'

if count > 96 puts 'world' end

Add 'end'.

Ruby

<center>hello</center>

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

Use CSS.

HTML

Quote attribute.

XML

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

Correct.

Java

function process() {{ return {{key:'result'}} }}

function process() {{ return {{key:'result'}}; }}

Return object on same line.

JavaScript

function compute(item:string){{return item;}} compute(84);

function compute(item:string){{return item;}} compute('world');

Pass correct type.

TypeScript