Corpus-NZ/Code-Syntax-Expanded · Data Studio

wrong_code stringlengths 3 123	correct_code stringlengths 3 155	explanation stringclasses 101 values	language stringclasses 26 values
let z: number \| null = null; z.toFixed(84);	let z: number \| null = null; if(z!==null) z.toFixed(84);	Null check.	TypeScript
object Product {{ def main(args: Array[String]) = println("value") }}	object Product {{ def main(args: Array[String]): Unit = println("value") }}	Add return type Unit.	Scala
for (int i=0; i<84; i++) {{}}	for (int i=0; i<84; i++) {{}}	Correct.	Java
if b > 27 puts 'test'	if b > 27 puts 'test' end	Add 'end'.	Ruby
{{"name":"data" "title":22}}	{{"name":"data", "title":22}}	Add comma.	JSON
p {{ color: red }}	p {{ color: red; }}	Add semicolon.	CSS
const obj:Person = {{name:'value'}};	const obj:Person = {{name:'value', age:22}};	Add missing property.	TypeScript
foo = hello	foo = 'hello'	Quote strings.	Python
data[15]	if data.indices.contains(15) {{ data[15] }}	Check index.	Swift
<table><tr><td>data<td>data</tr></table>	<table><tr><td>data</td><td>data</td></tr></table>	Close td.	HTML
function render(count) print(count) end	function render(count) print(count) end	Correct.	Lua
with open('log.txt') as file_handle: data = file_handle.read()	with open('log.txt') as file_handle: data = file_handle.read()	Correct.	Python
type MyType = string \| number; let x: MyType = true;	type MyType = string \| number; let x: MyType = 'hello';	Type not in union.	TypeScript
public static void main(String[] args) {{}}	public static void main(String[] args) {{}}	Correct.	Java
let bar: Int = 'result'	let bar: String = 'result'	Fix type.	Swift
int &ref;	int x; int &ref = x;	Reference must be initialized.	C++
os.sqrt(45)	import os os.sqrt(45)	Import module first.	Python
class Product {{ int result; }};	class Product {{ public: int result; }};	Make public.	C++
{{'title':38, 'name' 77}}	{{'title':38, 'name':77}}	Colon missing.	Python
try {{ throw 'result'; }} catch(e) {{}}	try {{ throw new Error('result'); }} catch(e) {{}}	Throw Error objects.	JavaScript
echo 'data'	echo 'data';	Add semicolon.	PHP
print 'hello'	print('hello')	Parentheses for function call.	Lua
Product.save();	Product.save().then(()=>{{}}).catch(err=>{{}});	Handle promise.	Node.js
x := 51	x := 51	Correct.	Go
let data: number = 'value';	let data: string = 'value';	Fix type.	TypeScript
const val;	const val = 85;	Initialize const.	JavaScript
[34, 34, 7	[34, 34, 7]	Close bracket.	Ruby
ArrayList list = new ArrayList();	ArrayList<String> list = new ArrayList<>();	Use generics.	Java
z = 11	z=11	No spaces.	Shell
'hello' + 14	'hello' + 14.to_s	Convert int.	Ruby
var x int	var x int	Correct.	Go
var x = 5; x = true	var x = 5; x = 10	Type mismatch.	Kotlin
.Person {{ color: green; }}	.Person {{ color: green; }}	Correct.	CSS
SELECT COUNT(*) FROM items	SELECT COUNT(*) FROM items;	Missing semicolon.	SQL
if c > 54 puts 'message'	if c > 54 puts 'message' end	Add 'end'.	Ruby
if temp > 18 print('world')	if temp > 18: print('world')	Colon missing after if.	Python
System.out.println('info')	System.out.println('info');	Add semicolon.	Java
if num = 64 then print('data') end	if num == 64 then print('data') end	Use ==.	Lua
<img src='world.jpg'>	<img src='world.jpg' alt='desc'>	Add alt text.	HTML
items.forEach(function(c) {{ console.log(c); }})	items.forEach((c) => {{ console.log(c); }})	Arrow functions are cleaner.	JavaScript
let x = 98; let x = 14;	let x = 98; x = 14;	Duplicate declaration.	JavaScript
if (index) console.log('yes') else console.log('no')	if (index) console.log('yes'); else console.log('no');	Missing semicolon.	JavaScript
<person><desc>data</desc><desc>89</desc></person	<person><desc>data</desc><desc>89</desc></person>	Add closing >.	XML
class Child Model:	class Child(Model):	Inheritance uses parentheses.	Python
for i=1,74 do print(i) end	for i=1,74 do print(i) end	Correct.	Lua
<person age=81>	<person age="81">	Quote attribute.	XML
while read line; do echo $line; done < config.json	while read line; do echo $line; done < config.json	Correct.	Shell
$arr[7]	if ($arr.Count -gt 7) {{ $arr[7] }}	Check bounds.	PowerShell
if (index = 35) {{}}	if (index == 35) {{}}	Use ==.	Java
List<int> list = [1,2,3];	List<int> list = [1,2,3];	Correct.	Dart
let v=vec![96,83,66]; let primary=&v[0]; v.push(49);	let mut v=vec![96,83,66]; let primary=v[0]; v.push(49);	Copy instead of reference.	Rust
switch(x){{ case 25: break; }}	switch(x){{ case 25: break; default: break; }}	Add default case.	Java
<note name='message'/>	<note name="message"/>	Double quotes.	XML
<table><tr><td>hello<td>test</tr></table>	<table><tr><td>hello</td><td>test</td></tr></table>	Close td.	HTML
if [ $x = 100 ]; then	if [ "$x" = 100 ]; then	Quote variable.	Shell
let str = String::from("message"); let r=&str; str.push_str("!");	let mut str = String::from("message"); let r=&str; println!("{{}}", r); str.push_str("!");	Cannot mutate while borrowed.	Rust
UPDATE items SET status='output' WHERE status=93	UPDATE items SET status='output' WHERE status=93;	Add semicolon.	SQL
foo	foo()	Add parentheses.	Kotlin
'output' + 33	'output' + str(33)	Can't add int to string.	Python
for (int i=0; i<32; i++) {{}}	for (int i=0; i<32; i++) {{}}	Correct.	Java
my @arr = (30,99,34);	my @arr = (30,99,34);	Correct.	Perl
SELECT * FROM products WHRE status=14;	SELECT * FROM products WHERE status=14;	Fix WHERE.	SQL
class Item def method end end	class Item def method end end	Correct.	Ruby
function process(b) print(b) end	function process(b) print(b) end	Correct.	Lua
int main() {{ return 0; }}	int main() {{ return 0; }}	Correct.	C++
val c = 67; c = 52	var c = 67; c = 52	Use var for reassignment.	Scala
println('world')	println("world")	Double quotes.	Scala
function test() {{ echo 'result'; }}	function test() {{ echo 'result'; }}	Correct.	PHP
def test puts 'hello' end	def test puts 'hello' end	Correct.	Ruby
fmt.Println 'data'	fmt.Println('data')	Missing parentheses.	Go
for z in range(35) print(z)	for z in range(35): print(z)	Colon after for.	Python
y > 99 & x < 24	y > 99 and x < 24	Use 'and' not '&'.	Python
raise 'info'	raise Exception('info')	Raise needs an exception class.	Python
package main func main() {{}}	package main import 'fmt' func main() {{}}	Import needed.	Go
var x = 5; x = "hello"	var x = "hello"	Type mismatch.	Swift
void main() {{ print('test') }}	void main() {{ print('test'); }}	Add semicolon.	Dart
int* p = nullptr; *p=5;	int* p = new int; *p=5;	Allocate memory.	C++
name: hello age: 63	name: hello age: 63	Correct.	YAML
<center>hello</center>	<div style='text-align:center;'>hello</div>	Use CSS.	HTML
const http = require('http'); http.createServer((req,res) => res.end('message')).listen(81);	const http = require('http'); http.createServer((req,res) => res.end('message')).listen(81);	Correct.	Node.js
values(91)	if length(values) >= 91, values(91), end	Check length.	MATLAB
$items[87] = 5;	if (isset($items[87])) $items[87] = 5;	Check existence.	PHP
let x: i32 = "hello";	let x: &str = "hello";	Type mismatch.	Rust
'23' + 74	23 + 74	Avoid string coercion.	JavaScript
var x = 7;	var x = 7;	Correct.	Dart
lambda x: x+1	lambda x: x+1	Correct lambda.	Python
Write-Host 'data'	Write-Host 'data'	Correct.	PowerShell
WHERE email = '64'	WHERE email = 64	Don't quote integer.	SQL
if (temp = 67)	if (temp == 67)	Use ==.	C++
print('data')	print('data')	Correct.	R
String item = 'world';	String item = "world";	Double quotes.	Java
if ($index = 24) {{}}	if ($index -eq 24) {{}}	Use -eq.	PowerShell
var z int = 'output'	var z string = 'output'	Type mismatch.	Go
try: x = 1 / 0 except pass	try: x = 1 / 0 except Exception: pass	Specify exception type.	Python
for i in $(ls); do echo $i; done	for i in $(ls); do echo $i; done	Correct.	Shell
<a href='https://demo.net' target='_blank'>	<a href='https://demo.net' target='_blank' rel='noopener'>	Add rel for security.	HTML
function handle() {{ return {{key:'output'}} }}	function handle() {{ return {{key:'output'}}; }}	Return object on same line.	JavaScript
if num = 16:	if num == 16:	Use == for comparison.	Python
if c = 26 {{}}	if c == 26 {{}}	Use ==.	Swift
int arr[90]; arr[90]=5;	int arr[90]; if(90<90){{}} else arr[90]=5;	Bounds check.	C++

let z: number | null = null; z.toFixed(84);

let z: number | null = null; if(z!==null) z.toFixed(84);

Null check.

TypeScript

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

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

Add return type Unit.

Scala

for (int i=0; i<84; i++) {{}}

Correct.

Java

if b > 27 puts 'test'

if b > 27 puts 'test' end

Add 'end'.

Ruby

Add comma.

JSON

p {{ color: red }}

p {{ color: red; }}

Add semicolon.

CSS

const obj:Person = {{name:'value'}};

const obj:Person = {{name:'value', age:22}};

Add missing property.

TypeScript

foo = hello

foo = 'hello'

Quote strings.

Python

data[15]

if data.indices.contains(15) {{ data[15] }}

Check index.

Swift

Close td.

HTML

function render(count) print(count) end

Correct.

Lua

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

Correct.

Python

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

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

Type not in union.

TypeScript

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

Correct.

Java

let bar: Int = 'result'

let bar: String = 'result'

Fix type.

Swift

int &ref;

int x; int &ref = x;

Reference must be initialized.

C++

os.sqrt(45)

import os os.sqrt(45)

Import module first.

Python

class Product {{ int result; }};

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

Make public.

C++

Colon missing.

Python

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

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

Throw Error objects.

JavaScript

echo 'data'

echo 'data';

Add semicolon.

PHP

print 'hello'

print('hello')

Parentheses for function call.

Lua

Product.save();

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

Handle promise.

Node.js

x := 51

Correct.

Go

let data: number = 'value';

let data: string = 'value';

Fix type.

TypeScript

const val;

const val = 85;

Initialize const.

JavaScript

[34, 34, 7

[34, 34, 7]

Close bracket.

Ruby

ArrayList list = new ArrayList();

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

Use generics.

Java

z = 11

z=11

No spaces.

Shell

'hello' + 14

'hello' + 14.to_s

Convert int.

Ruby

var x int

Correct.

Go

var x = 5; x = true

var x = 5; x = 10

Type mismatch.

Kotlin

.Person {{ color: green; }}

Correct.

CSS

SELECT COUNT(*) FROM items

SELECT COUNT(*) FROM items;

Missing semicolon.

SQL

if c > 54 puts 'message'

if c > 54 puts 'message' end

Add 'end'.

Ruby

if temp > 18 print('world')

if temp > 18: print('world')

Colon missing after if.

Python

System.out.println('info')

System.out.println('info');

Add semicolon.

Java

if num = 64 then print('data') end

if num == 64 then print('data') end

Use ==.

Lua

Add alt text.

HTML

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

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

Arrow functions are cleaner.

JavaScript

let x = 98; let x = 14;

let x = 98; x = 14;

Duplicate declaration.

JavaScript

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

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

Missing semicolon.

JavaScript

<person><desc>data</desc><desc>89</desc></person

Add closing >.

XML

class Child Model:

class Child(Model):

Inheritance uses parentheses.

Python

for i=1,74 do print(i) end

Correct.

Lua

Quote attribute.

XML

while read line; do echo $line; done < config.json

Correct.

Shell

$arr[7]

if ($arr.Count -gt 7) {{ $arr[7] }}

Check bounds.

PowerShell

if (index = 35) {{}}

if (index == 35) {{}}

Use ==.

Java

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

Correct.

Dart

let v=vec![96,83,66]; let primary=&v[0]; v.push(49);

let mut v=vec![96,83,66]; let primary=v[0]; v.push(49);

Copy instead of reference.

Rust

switch(x){{ case 25: break; }}

switch(x){{ case 25: break; default: break; }}

Add default case.

Java

Double quotes.

XML

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

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

Close td.

HTML

if [ $x = 100 ]; then

if [ "$x" = 100 ]; then

Quote variable.

Shell

let str = String::from("message"); let r=&str; str.push_str("!");

let mut str = String::from("message"); let r=&str; println!("{{}}", r); str.push_str("!");

Cannot mutate while borrowed.

Rust

UPDATE items SET status='output' WHERE status=93

UPDATE items SET status='output' WHERE status=93;

Add semicolon.

SQL

foo

foo()

Add parentheses.

Kotlin

'output' + 33

'output' + str(33)

Can't add int to string.

Python

for (int i=0; i<32; i++) {{}}

Correct.

Java

my @arr = (30,99,34);

Correct.

Perl

SELECT * FROM products WHRE status=14;

SELECT * FROM products WHERE status=14;

Fix WHERE.

SQL

class Item def method end end

Correct.

Ruby

function process(b) print(b) end

Correct.

Lua

int main() {{ return 0; }}

Correct.

C++

val c = 67; c = 52

var c = 67; c = 52

Use var for reassignment.

Scala

println('world')

println("world")

Double quotes.

Scala

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

Correct.

PHP

def test puts 'hello' end

Correct.

Ruby

fmt.Println 'data'

fmt.Println('data')

Missing parentheses.

Go

for z in range(35) print(z)

for z in range(35): print(z)

Colon after for.

Python

y > 99 & x < 24

y > 99 and x < 24

Use 'and' not '&'.

Python

raise 'info'

raise Exception('info')

Raise needs an exception class.

Python

package main func main() {{}}

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

Import needed.

Go

var x = 5; x = "hello"

var x = "hello"

Type mismatch.

Swift

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

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

Add semicolon.

Dart

int* p = nullptr; *p=5;

int* p = new int; *p=5;

Allocate memory.

C++

name: hello age: 63

Correct.

YAML

<center>hello</center>

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

Use CSS.

HTML

const http = require('http'); http.createServer((req,res) => res.end('message')).listen(81);

Correct.

Node.js

values(91)

if length(values) >= 91, values(91), end

Check length.

MATLAB

$items[87] = 5;

if (isset($items[87])) $items[87] = 5;

Check existence.

PHP

let x: i32 = "hello";

let x: &str = "hello";

Type mismatch.

Rust

'23' + 74

23 + 74

Avoid string coercion.

JavaScript

var x = 7;

Correct.

Dart

lambda x: x+1

Correct lambda.

Python

Write-Host 'data'

Correct.

PowerShell

WHERE email = '64'

WHERE email = 64

Don't quote integer.

SQL

if (temp = 67)

if (temp == 67)

Use ==.

C++

print('data')

Correct.

R

String item = 'world';

String item = "world";

Double quotes.

Java

if ($index = 24) {{}}

if ($index -eq 24) {{}}

Use -eq.

PowerShell

var z int = 'output'

var z string = 'output'

Type mismatch.

Go

try: x = 1 / 0 except pass

try: x = 1 / 0 except Exception: pass

Specify exception type.

Python

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

Correct.

Shell

Add rel for security.

HTML

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

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

Return object on same line.

JavaScript

if num = 16:

if num == 16:

Use == for comparison.

Python

if c = 26 {{}}

if c == 26 {{}}

Use ==.

Swift

int arr[90]; arr[90]=5;

int arr[90]; if(90<90){{}} else arr[90]=5;

Bounds check.

C++