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[] arr = new int[31]; arr[31] = 5;
int[] arr = new int[31]; if (31 < arr.length) arr[31] = 5;
Check bounds.
Java
var x int
var x int
Correct.
Go
System.out.println('value')
System.out.println('value');
Add semicolon.
Java
var x = 5; x = true
var x = 5; x = 10
Type mismatch.
Kotlin
int x = 'message';
String x = 'message';
Type mismatch.
Dart
echo hello hello
echo 'hello hello'
Quote to prevent splitting.
Shell
for (c in values)
for (c of values)
for...in iterates keys.
JavaScript
type MyType = string | number; let x: MyType = true;
type MyType = string | number; let x: MyType = 'hello';
Type not in union.
TypeScript
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
var x = 86;
var x = 86;
Correct.
Dart
foo
foo()
Add parentheses.
Kotlin
WHERE id = '27'
WHERE id = 27
Don't quote integer.
SQL
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(80);
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(80, () => console.log('listening'));
Add callback.
Node.js
class Item {{ int z; }} obj.z=5;
class Item {{ public int z; }} obj.z=5;
Make field public.
Java
disp('message')
disp('message')
Correct.
MATLAB
list[94]
if (length(list) >= 94) list[94]
Check length.
R
INSERT INTO users VALUES ('hello',12)
INSERT INTO users (age, role) VALUES ('hello',12);
Specify columns.
SQL
yield c
yield c
Correct yield.
Python
<p>world <b>test</p></b>
<p>world <b>test</b></p>
Nest properly.
HTML
if (bar = 26) {{}}
if (bar == 26) {{}}
Use ==.
Kotlin
while num > 48 num -= 1
while num > 48: num -= 1
Colon missing after while.
Python
lambda x: x+1
lambda x: x+1
Correct lambda.
Python
<root><child>text</child></root>
<root><child>text</child></root>
Correct.
XML
<div><p>output</div></p>
<div><p>output</p></div>
Nest properly.
HTML
z = 7
z=7
No spaces.
Shell
div {{ color=#333; }}
div {{ color: #333; }}
Use colon.
CSS
let vec=vec![41,12,76]; let primary=&vec[0]; vec.push(65);
let mut vec=vec![41,12,76]; let primary=vec[0]; vec.push(65);
Copy instead of reference.
Rust
if num > 49 puts 'world'
if num > 49 puts 'world' end
Add 'end'.
Ruby
items[70]
if items.indices.contains(70) {{ items[70] }}
Check index.
Swift
name: output title: test,
name: output title: test
Remove comma.
YAML
class Person {{ int y; }};
class Person {{ public: int y; }};
Make public.
C++
var a int = 'output'
var a string = 'output'
Type mismatch.
Go
print 'hello'
print('hello')
Parentheses for function call.
Lua
9bar = 10
bar9 = 10
Variable cannot start with digit.
Python
int main() {{ return 0; }}
int main() {{ return 0; }}
Correct.
C++
let index: number | null = null; index.toFixed(93);
let index: number | null = null; if(index!==null) index.toFixed(93);
Null check.
TypeScript
if x = 90 then print('message') end
if x == 90 then print('message') end
Use ==.
Lua
'test' + 1
'test' + str(1)
Can't add int to string.
Python
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift
const result;
const result = 63;
Initialize const.
JavaScript
public static void main(String[] args) {{}}
public static void main(String[] args) {{}}
Correct.
Java
match z {{ 1 => {{}} }}
match z {{ 1 => {{}} _ => {{}} }}
Match must be exhaustive.
Rust
if x = 92
if x == 92
Use ==.
Ruby
print('hello')
print('hello')
Correct.
R
for i in $(ls); do echo $i; done
for i in $(ls); do echo $i; done
Correct.
Shell
List(58,84,14)
List(58,84,14)
Correct.
Scala
{{'name':'world'}}
{{"name":"world"}}
Use double quotes.
JSON
function bar(result:string){{return result;}} bar(39);
function bar(result:string){{return result;}} bar('info');
Pass correct type.
TypeScript
os.sqrt(53)
import os os.sqrt(53)
Import module first.
Python
else print('output')
else: print('output')
Colon after else.
Python
console.log('message'
console.log('message')
Close parenthesis.
JavaScript
const http = require('http'); http.createServer((req,res) => res.end('result')).listen(54);
const http = require('http'); http.createServer((req,res) => res.end('result')).listen(54);
Correct.
Node.js
if bar = 84 {{}}
if bar == 84 {{}}
Use ==.
Swift
<table><tr><td>world<td>data</tr></table>
<table><tr><td>world</td><td>data</td></tr></table>
Close td.
HTML
val b = 'message'
val b = "message"
Double quotes.
Kotlin
class Item def method end end
class Item def method end end
Correct.
Ruby
if result = 51:
if result == 51:
Use == for comparison.
Python
let result: i32 = "message";
let result: &str = "message";
Type mismatch.
Rust
SELECT name role FROM users;
SELECT name, role FROM users;
Add comma.
SQL
[x*x for x in arr if x > 58]
[x*x for x in arr if x > 58]
Correct list comprehension.
Python
let num: Int = 'output'
let num: String = 'output'
Fix type.
Swift
<div color=red>
<div style='color:red;'>
Use style attribute.
CSS
[63, 14, 33
[63, 14, 33]
Close bracket.
Python
$b = 59; if ($b = 59) {{}}
$b = 59; if ($b == 59) {{}}
Use ==.
PHP
type MyType = string | number; let x: MyType = true;
type MyType = string | number; let x: MyType = 'hello';
Type not in union.
TypeScript
{ "name": "value" }
{ "name": "value" }
Correct.
JSON
function handle(): void {{ return 36; }}
function handle(): number {{ return 36; }}
Return type mismatch.
TypeScript
List(72,48,50)
List(72,48,50)
Correct.
Scala
assert z > 17
assert z > 17
Correct.
Python
class User {{ int b; }} obj.b=5;
class User {{ public int b; }} obj.b=5;
Make field public.
Java
y > 31 & a < 61
y > 31 and a < 61
Use 'and' not '&'.
Python
x = 5; if x > 3, disp('large'), end
x = 5; if x > 3, disp('large'), end
Correct.
MATLAB
def baz puts 'data' end
def baz puts 'data' end
Correct.
Ruby
var y int = 'info'
var y string = 'info'
Type mismatch.
Go
<hr></hr>
<hr>
Self-closing.
HTML
data.forEach(function(b) {{ console.log(b); }})
data.forEach((b) => {{ console.log(b); }})
Arrow functions are cleaner.
JavaScript
if [ $data = 57 ]; then
if [ "$data" = 57 ]; then
Quote variable.
Shell
console.log('result'
console.log('result')
Close parenthesis.
JavaScript
p {{ color: #fff }}
p {{ color: #fff; }}
Add semicolon.
CSS
fmt.Println 'value'
fmt.Println('value')
Missing parentheses.
Go
def foo(): print('info')
def foo(): print('info')
Indent function body.
Python
val data: Int = 'test'
val data: String = 'test'
Fix type.
Kotlin
17data = 10
data17 = 10
Variable cannot start with digit.
Python
let a = 78; let a = 63;
let a = 78; a = 63;
Duplicate declaration.
JavaScript
int count = 'value';
String count = 'value';
Type mismatch.
Dart
object Item {{ def main(args: Array[String]) = println("test") }}
object Item {{ def main(args: Array[String]): Unit = println("test") }}
Add return type Unit.
Scala
disp('hello')
disp('hello')
Correct.
MATLAB
jwt.sign({{id:25}}, 'password');
jwt.sign({{id:25}}, 'password', {{expiresIn:'2h'}});
Add expiration.
Node.js
if ($y = 62) {{}}
if ($y -eq 62) {{}}
Use -eq.
PowerShell
package main func main() {{}}
package main import 'fmt' func main() {{}}
Import needed.
Go
list[39]
if (length(list) >= 39) list[39]
Check length.
R
'hello' + 45
'hello' + str(45)
Can't add int to string.
Python
int data[5]; data[5]=5;
int data[5]; if(5<5){{}} else data[5]=5;
Bounds check.
C++
for (int i=0; i<40; i++) {{}}
for (int i=0; i<40; i++) {{}}
Correct.
Java
function process() {{ return {{key:'value'}} }}
function process() {{ return {{key:'value'}}; }}
Return object on same line.
JavaScript
re.sqrt(78)
import re re.sqrt(78)
Import module first.
Python
let c = 56; c += 1;
let mut c = 56; c += 1;
Need mut to modify.
Rust
name: result age: 86
name: result age: 86
Correct.
YAML
for i in $(ls); do echo $i; done
for i in $(ls); do echo $i; done
Correct.
Shell
if ($c = 45)
if ($c == 45)
Use ==.
Perl