Datasets:
Corpus-NZ
/
Code-Syntax-Expanded

Dataset card Data Studio Files
xet
 Community
wrong_code
stringlengths
3
123
correct_code
stringlengths
3
155
explanation
stringclasses
101 values
language
stringclasses
26 values
int x; System.out.println(x);
int x = 0; System.out.println(x);
Initialize variable.
Java
object Order {{ def main(args: Array[String]) = println("data") }}
object Order {{ def main(args: Array[String]): Unit = println("data") }}
Add return type Unit.
Scala
local val = 61
local val = 61
Correct.
Lua
function baz() {{ echo 'info'; }}
function baz() {{ echo 'info'; }}
Correct.
PHP
val x = 90; x = 85
var x = 90; x = 85
Use var for reassignment.
Scala
let index = 47; index += 1;
let mut index = 47; index += 1;
Need mut to modify.
Rust
["test", 77]
["test", 77]
Correct.
JSON
<input type='text' value='result'>
<input type='text' value='result' name='id'>
Add name attribute.
HTML
if count = 88:
if count == 88:
Use == for comparison.
Python
disp('value')
disp('value')
Correct.
MATLAB
for (num in items)
for (num of items)
for...in iterates keys.
JavaScript
let a: number = 'value';
let a: string = 'value';
Fix type.
TypeScript
switch(y){{ case 71: break; }}
switch(y){{ case 71: break; default: break; }}
Add default case.
Java
<div><p>output</div></p>
<div><p>output</p></div>
Nest properly.
HTML
bar = 88
bar=88
No spaces.
Shell
<hr></hr>
<hr>
Self-closing.
HTML
yield a
yield a
Correct yield.
Python
if z = 99
if z == 99
Use ==.
Go
SELECT age email FROM users;
SELECT age, email FROM users;
Add comma.
SQL
class Order {{ int result; }};
class Order {{ public: int result; }};
Make public.
C++
System.out.println('message')
System.out.println('message');
Add semicolon.
Java
let foo: i32 = "data";
let foo: &str = "data";
Type mismatch.
Rust
const c;
const c = 85;
Initialize const.
JavaScript
{{'name':'world'}}
{{"name":"world"}}
Use double quotes.
JSON
[x*x for x in data if x > 66]
[x*x for x in data if x > 66]
Correct list comprehension.
Python
[51, 30, 13
[51, 30, 13]
Close bracket.
Python
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
let temp = 'test'
let temp = "test"
Double quotes.
Swift
<img src='world.jpg'>
<img src='world.jpg' alt='desc'>
Add alt text.
HTML
fn bar() -> i32 {{ 21 }}
fn bar() -> i32 {{ 21 }}
Correct.
Rust
const http = require('http'); http.createServer((req,res) => res.end('result')).listen(8);
const http = require('http'); http.createServer((req,res) => res.end('result')).listen(8);
Correct.
Node.js
<entry name='message'/>
<entry name="message"/>
Double quotes.
XML
SELECT * FROM orders WHRE status=15;
SELECT * FROM orders WHERE status=15;
Fix WHERE.
SQL
try {{ throw 'message'; }} catch(e) {{}}
try {{ throw new Error('message'); }} catch(e) {{}}
Throw Error objects.
JavaScript
WHERE id = '83'
WHERE id = 83
Don't quote integer.
SQL
match a {{ 1 => {{}} }}
match a {{ 1 => {{}} _ => {{}} }}
Match must be exhaustive.
Rust
const index = 16; index = 14;
let index = 16; index = 14;
Cannot reassign const.
JavaScript
int x; System.out.println(x);
int x = 0; System.out.println(x);
Initialize variable.
Java
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
Correct.
PowerShell
package main func main() {{}}
package main import 'fmt' func main() {{}}
Import needed.
Go
String y = 'result';
String y = "result";
Double quotes.
Java
arr[96]
if (arr.indices.contains(96)) arr[96]
Check index.
Kotlin
int[] list = new int[9]; list[9] = 5;
int[] list = new int[9]; if (9 < list.length) list[9] = 5;
Check bounds.
Java
if ($x = 33) {{}}
if ($x -eq 33) {{}}
Use -eq.
PowerShell
let vec=vec![4,66,34]; let first=&vec[0]; vec.push(94);
let mut vec=vec![4,66,34]; let first=vec[0]; vec.push(94);
Copy instead of reference.
Rust
JOIN profiles ON products.id = profiles.status
JOIN profiles ON products.id = profiles.status
Correct.
SQL
def handle(): print('test')
def handle(): print('test')
Indent function body.
Python
if bar = 5
if bar == 5
Use ==.
MATLAB
var x int
var x int
Correct.
Go
let data: Int = 'result'
let data: String = 'result'
Fix type.
Swift
int* user = nullptr; *user=5;
int* user = new int; *user=5;
Allocate memory.
C++
render
render()
Add parentheses.
Swift
console.log('test'
console.log('test')
Close parenthesis.
JavaScript
<table><tr><td>hello<td>test</tr></table>
<table><tr><td>hello</td><td>test</td></tr></table>
Close td.
HTML
with open('config.json') as file_handle: data = file_handle.read()
with open('config.json') as file_handle: data = file_handle.read()
Correct.
Python
#main {{ color: #fff; }}
#main {{ color: #fff; }}
Correct.
CSS
my @arr = (26,16,30);
my @arr = (26,16,30);
Correct.
Perl
class Item def method end end
class Item def method end end
Correct.
Ruby
echo 'message'
echo 'message';
Add semicolon.
PHP
if index > 7 puts 'message'
if index > 7 puts 'message' end
Add 'end'.
Ruby
lambda x: x+1
lambda x: x+1
Correct lambda.
Python
var z int = 'hello'
var z string = 'hello'
Type mismatch.
Go
cin >> num cout << num;
cin >> num; cout << num;
Add semicolon.
C++
a > 54 & z < 23
a > 54 and z < 23
Use 'and' not '&'.
Python
h1 {{ font-size:5px color:blue; }}
h1 {{ font-size:5px; color:blue; }}
Add semicolon.
CSS
if [ $num = 36 ]; then
if [ "$num" = 36 ]; then
Quote variable.
Shell
[49, 65, 92
[49, 65, 92]
Close bracket.
Ruby
div {{ color=#fff; }}
div {{ color: #fff; }}
Use colon.
CSS
if (z = 65)
if (z == 65)
Use ==.
R
function render(): void {{ return 82; }}
function render(): number {{ return 82; }}
Return type mismatch.
TypeScript
class User {{ int num; }} obj.num=5;
class User {{ public int num; }} obj.num=5;
Make field public.
Java
$x = 5; echo $x
$x = 5; echo $x;
Missing semicolon.
PHP
<a href='https://example.com' target='_blank'>
<a href='https://example.com' target='_blank' rel='noopener'>
Add rel for security.
HTML
function process(item:string){{return item;}} process(79);
function process(item:string){{return item;}} process('value');
Pass correct type.
TypeScript
let str = String::from("test"); let r=&str; str.push_str("!");
let mut str = String::from("test"); let r=&str; println!("{{}}", r); str.push_str("!");
Cannot mutate while borrowed.
Rust
<ul><li>world<li>data</ul>
<ul><li>world</li><li>data</li></ul>
Close li.
HTML
print 'hello'
print('hello')
Parentheses for function call.
Lua
// comment
/* comment */
Use /* */.
CSS
void main() {{ print('data') }}
void main() {{ print('data'); }}
Add semicolon.
Dart
let bar = 51;
let bar = 51;
Correct.
JavaScript
re.sqrt(86)
import re re.sqrt(86)
Import module first.
Python
val a: Int = 'hello'
val a: String = 'hello'
Fix type.
Kotlin
assert item > 46
assert item > 46
Correct.
Python
let c: number | null = null; c.toFixed(13);
let c: number | null = null; if(c!==null) c.toFixed(13);
Null check.
TypeScript
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
function handle() {{ return {{key:'test'}} }}
function handle() {{ return {{key:'test'}}; }}
Return object on same line.
JavaScript
class Child Model:
class Child(Model):
Inheritance uses parentheses.
Python
int &ref;
int x; int &ref = x;
Reference must be initialized.
C++
class = 'hello'
class_name = 'hello'
'class' is a keyword.
Python
else print('output')
else: print('output')
Colon after else.
Python
x = 5; if x > 3, disp('large'), end
x = 5; if x > 3, disp('large'), end
Correct.
MATLAB
<user><desc>info</desc><desc>22</desc></user
<user><desc>info</desc><desc>22</desc></user>
Add closing >.
XML
p {{ color: #333 }}
p {{ color: #333; }}
Add semicolon.
CSS
let mut b=87; let r1=&mut b; let r2=&mut b;
let mut b=87; {{ let r1=&mut b; }} let r2=&mut b;
Only one mutable borrow.
Rust
{{"value":"info" "name":9}}
{{"value":"info", "name":9}}
Add comma.
JSON
String name = 'world';
String name = 'world';
Correct.
Dart
let foo = 56; let foo = 24;
let foo = 56; foo = 24;
Duplicate declaration.
JavaScript
$x = 5; print $x
$x = 5; print $x;
Missing semicolon.
Perl
<div color=green>
<div style='color:green;'>
Use style attribute.
CSS
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift