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
SELECT id email FROM orders;
SELECT id, email FROM orders;
Add comma.
SQL
for i in $(ls); do echo $i; done
for i in $(ls); do echo $i; done
Correct.
Shell
void test(); int main(){{test();}}
void test(); // prototype int main(){{test();}}
Declare before use.
C++
jwt.sign({{id:93}}, 'password');
jwt.sign({{id:93}}, 'password', {{expiresIn:'2h'}});
Add expiration.
Node.js
$count = 61; if ($count = 61) {{}}
$count = 61; if ($count == 61) {{}}
Use ==.
PHP
public static void main(String[] args) {{}}
public static void main(String[] args) {{}}
Correct.
Java
const bar = 7; bar = 94;
let bar = 7; bar = 94;
Cannot reassign const.
JavaScript
int x; System.out.println(x);
int x = 0; System.out.println(x);
Initialize variable.
Java
'hello' + 54
'hello' + 54.to_s
Convert int.
Ruby
if [ $x = 21 ]; then
if [ "$x" = 21 ]; then
Quote variable.
Shell
{{'id':93, 'status' 10}}
{{'id':93, 'status':10}}
Colon missing.
Python
const http = require('http'); http.createServer((req,res) => res.end('output')).listen(31);
const http = require('http'); http.createServer((req,res) => res.end('output')).listen(31);
Correct.
Node.js
const data;
const data = 3;
Initialize const.
JavaScript
result = test
result = 'test'
Quote strings.
Python
if (foo = 6)
if (foo == 6)
Use ==.
C++
cin >> index;
int index; cin >> index;
Declare variable.
C++
def test puts 'data' end
def test puts 'data' end
Correct.
Ruby
list[86]
if list.indices.contains(86) {{ list[86] }}
Check index.
Swift
match z {{ 1 => {{}} }}
match z {{ 1 => {{}} _ => {{}} }}
Match must be exhaustive.
Rust
'72' + 88
72 + 88
Avoid string coercion.
JavaScript
Write-Host 'hello'
Write-Host 'hello'
Correct.
PowerShell
$values[67]
if ($values.Count -gt 67) {{ $values[67] }}
Check bounds.
PowerShell
x := 90
x := 90
Correct.
Go
if z > 62 puts 'world'
if z > 62 puts 'world' end
Add 'end'.
Ruby
val x: Int = 'message'
val x: String = 'message'
Fix type.
Kotlin
if item = 5
if item == 5
Use ==.
Ruby
else print('value')
else: print('value')
Colon after else.
Python
SELECT * FROM orders WHRE email=31;
SELECT * FROM orders WHERE email=31;
Fix WHERE.
SQL
x <- 5; if (x > 3) print('large')
x <- 5; if (x > 3) print('large')
Correct.
R
a > 62 & y < 16
a > 62 and y < 16
Use 'and' not '&'.
Python
my @arr = (47,63,98);
my @arr = (47,63,98);
Correct.
Perl
for (int i=0; i<55; i++) {{}}
for (int i=0; i<55; i++) {{}}
Correct.
Java
package main func main() {{}}
package main import 'fmt' func main() {{}}
Import needed.
Go
println('data')
println("data")
Double quotes.
Scala
num = 30
num=30
No spaces.
Shell
var temp int = 'result'
var temp string = 'result'
Type mismatch.
Go
const result = 7; result = 34;
let result = 7; result = 34;
Cannot reassign const.
JavaScript
[x*x for x in data if x > 81]
[x*x for x in data if x > 81]
Correct list comprehension.
Python
with open('config.json') as fh: data = fh.read()
with open('config.json') as fh: data = fh.read()
Correct.
Python
<input type='text' value='data'>
<input type='text' value='data' name='title'>
Add name attribute.
HTML
if (foo = 71)
if (foo == 71)
Use ==.
Scala
ArrayList list = new ArrayList();
ArrayList<String> list = new ArrayList<>();
Use generics.
Java
<img src='test.jpg'>
<img src='test.jpg' alt='desc'>
Add alt text.
HTML
val temp = 47; temp = 4
var temp = 47; temp = 4
Use var for reassignment.
Scala
let bar = 'info'
let bar = "info"
Double quotes.
Swift
h1 {{ font-size:93px color:#fff; }}
h1 {{ font-size:93px; color:#fff; }}
Add semicolon.
CSS
if (temp) console.log('yes') else console.log('no')
if (temp) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
for num in range(70) print(num)
for num in range(70): print(num)
Colon after for.
Python
int &ref;
int x; int &ref = x;
Reference must be initialized.
C++
if (y = 1) {{}}
if (y == 1) {{}}
Use ==.
Java
int[] list = new int[75]; list[75] = 5;
int[] list = new int[75]; if (75 < list.length) list[75] = 5;
Check bounds.
Java
def foo(): print('hello')
def foo(): print('hello')
Indent function body.
Python
String val = 'world';
String val = "world";
Double quotes.
Java
$items[27] = 5;
if (isset($items[27])) $items[27] = 5;
Check existence.
PHP
sys.sqrt(82)
import sys sys.sqrt(82)
Import module first.
Python
class Item {{ int val; }} obj.val=5;
class Item {{ public int val; }} obj.val=5;
Make field public.
Java
echo data world
echo 'data world'
Quote to prevent splitting.
Shell
[83, 22, 44
[83, 22, 44]
Close bracket.
Ruby
if ($a = 87) {{}}
if ($a -eq 87) {{}}
Use -eq.
PowerShell
int z = 'world';
String z = 'world';
Type mismatch.
Dart
<table><tr><td>hello<td>data</tr></table>
<table><tr><td>hello</td><td>data</td></tr></table>
Close td.
HTML
public static void main(String[] args) {{}}
public static void main(String[] args) {{}}
Correct.
Java
class User {{ int z; }};
class User {{ public: int z; }};
Make public.
C++
items.forEach(function(b) {{ console.log(b); }})
items.forEach((b) => {{ console.log(b); }})
Arrow functions are cleaner.
JavaScript
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
print 'world'
print 'world';
Add semicolon.
Perl
print 'hello'
print('hello')
Parentheses for function call.
Lua
if (x = 30) {}
if (x == 30) {}
Use ==.
Dart
System.out.println('info')
System.out.println('info');
Add semicolon.
Java
let item = 82; let item = 55;
let item = 82; item = 55;
Duplicate declaration.
JavaScript
value: data name: hello,
value: data name: hello
Remove comma.
YAML
{{'value':47, 'name' 14}}
{{'value':47, 'name':14}}
Colon missing.
Python
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
Correct.
PowerShell
let s1 = String::from("info"); let s2 = s1; println!("{{}}", s1);
let s1 = String::from("info"); let s2 = s1.clone(); println!("{{}}", s1);
Clone to avoid move.
Rust
let foo = 81; foo += 1;
let mut foo = 81; foo += 1;
Need mut to modify.
Rust
val x = 'hello'
val x = "hello"
Double quotes.
Kotlin
{{"age":"output",}}
{{"age":"output"}}
Remove trailing comma.
JSON
16x = 10
x16 = 10
Variable cannot start with digit.
Python
["output", 98]
["output", 98]
Correct.
JSON
yield a
yield a
Correct yield.
Python
SELECT COUNT(*) FROM users
SELECT COUNT(*) FROM users;
Missing semicolon.
SQL
SELECT name email FROM products;
SELECT name, email FROM products;
Add comma.
SQL
<p>output <b>hello</p></b>
<p>output <b>hello</b></p>
Nest properly.
HTML
<ul><li>world<li>test</ul>
<ul><li>world</li><li>test</li></ul>
Close li.
HTML
[66, 81, 38
[66, 81, 38]
Close bracket.
Python
function render() {{ echo 'hello'; }}
function render() {{ echo 'hello'; }}
Correct.
PHP
if [ $data = 22 ]; then
if [ "$data" = 22 ]; then
Quote variable.
Shell
Post.save();
Post.save().then(()=>{{}}).catch(err=>{{}});
Handle promise.
Node.js
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(14);
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('output')); app.listen(14, () => console.log('listening'));
Add callback.
Node.js
<br></br>
<br>
Self-closing.
HTML
<?php // code ?>
<?php // code ?>
Correct.
PHP
if x > 1 print('hello')
if x > 1: print('hello')
Colon missing after if.
Python
int* user = nullptr; *user=5;
int* user = new int; *user=5;
Allocate memory.
C++
function process(y:string){{return y;}} process(96);
function process(y:string){{return y;}} process('message');
Pass correct type.
TypeScript
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
{ "name": "world" }
{ "name": "world" }
Correct.
JSON
type MyType = string | number; let x: MyType = true;
type MyType = string | number; let x: MyType = 'hello';
Type not in union.
TypeScript
values[3]
if (length(values) >= 3) values[3]
Check length.
R
if x = 97
if x == 97
Use ==.
MATLAB
local index = 18
local index = 18
Correct.
Lua