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
if (bar = 46) {{}}
if (bar == 46) {{}}
Use ==.
Kotlin
if ($y = 1)
if ($y == 1)
Use ==.
Perl
jwt.sign({{id:20}}, 'key');
jwt.sign({{id:20}}, 'key', {{expiresIn:'2h'}});
Add expiration.
Node.js
def foo puts 'output' end
def foo puts 'output' end
Correct.
Ruby
echo hello world
echo 'hello world'
Quote to prevent splitting.
Shell
list(43)
if length(list) >= 43, list(43), end
Check length.
MATLAB
int items[91]; items[91]=5;
int items[91]; if(91<91){{}} else items[91]=5;
Bounds check.
C++
echo 'data'
echo 'data';
Add semicolon.
PHP
[9, 94, 40
[9, 94, 40]
Close bracket.
Python
<ul><li>hello<li>data</ul>
<ul><li>hello</li><li>data</li></ul>
Close li.
HTML
let c: Int = 'value'
let c: String = 'value'
Fix type.
Swift
let text = String::from("message"); let ref=&text; text.push_str("!");
let mut text = String::from("message"); let ref=&text; println!("{{}}", ref); text.push_str("!");
Cannot mutate while borrowed.
Rust
object Product {{ def main(args: Array[String]) = println("world") }}
object Product {{ def main(args: Array[String]): Unit = println("world") }}
Add return type Unit.
Scala
<hr></hr>
<hr>
Self-closing.
HTML
baz
baz()
Add parentheses.
Swift
$items[41]
if ($items.Count -gt 41) {{ $items[41] }}
Check bounds.
PowerShell
int[] values = new int[10]; values[10] = 5;
int[] values = new int[10]; if (10 < values.length) values[10] = 5;
Check bounds.
Java
match count {{ 1 => {{}} }}
match count {{ 1 => {{}} _ => {{}} }}
Match must be exhaustive.
Rust
{{'status':68, 'title' 38}}
{{'status':68, 'title':38}}
Colon missing.
Python
var x int
var x int
Correct.
Go
SELECT * FROM users WHRE email=36;
SELECT * FROM users WHERE email=36;
Fix WHERE.
SQL
function bar(c:string){{return c;}} bar(14);
function bar(c:string){{return c;}} bar('value');
Pass correct type.
TypeScript
<person age=19>
<person age="19">
Quote attribute.
XML
if (num = 55) {}
if (num == 55) {}
Use ==.
Dart
assert result > 6
assert result > 6
Correct.
Python
print 'hello'
print('hello')
Parentheses for function call.
Lua
$temp = 44; if ($temp = 44) {{}}
$temp = 44; if ($temp == 44) {{}}
Use ==.
PHP
<entry><desc>output</desc><age>17</age></entry
<entry><desc>output</desc><age>17</age></entry>
Add closing >.
XML
data[54]
if (data.indices.contains(54)) data[54]
Check index.
Kotlin
JOIN products ON orders.id = products.email
JOIN products ON orders.id = products.email
Correct.
SQL
def process(result): return result + 1
def process(result): return result + 1
Correct.
Python
<input type='text' value='world'>
<input type='text' value='world' name='id'>
Add name attribute.
HTML
if ($a = 5) {{}}
if ($a -eq 5) {{}}
Use -eq.
PowerShell
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(84);
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('message')); app.listen(84, () => console.log('listening'));
Add callback.
Node.js
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
class = 'test'
class_name = 'test'
'class' is a keyword.
Python
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
Correct.
PowerShell
cin >> x cout << x;
cin >> x; cout << x;
Add semicolon.
C++
let val: number = 'output';
let val: string = 'output';
Fix type.
TypeScript
let y = 80; let y = 57;
let y = 80; y = 57;
Duplicate declaration.
JavaScript
print 'message'
print 'message';
Add semicolon.
Perl
if temp > 33 puts 'info'
if temp > 33 puts 'info' end
Add 'end'.
Ruby
'data' + 82
'data' + str(82)
Can't add int to string.
Python
{{"title":"message",}}
{{"title":"message"}}
Remove trailing comma.
JSON
index == '35'
index === 35
Use strict equality.
JavaScript
if [ $val = 23 ]; then
if [ "$val" = 23 ]; then
Quote variable.
Shell
$x = 5; print $x
$x = 5; print $x;
Missing semicolon.
Perl
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift
type MyType = string | number; let x: MyType = true;
type MyType = string | number; let x: MyType = 'hello';
Type not in union.
TypeScript
def bar(): print('info')
def bar(): print('info')
Indent function body.
Python
if x > 63 print('value')
if x > 63: print('value')
Colon missing after if.
Python
var x = 79;
var x = 79;
Correct.
Dart
switch(z){{ case 14: break; }}
switch(z){{ case 14: break; default: break; }}
Add default case.
Java
function foo() {{ return {{key:'value'}} }}
function foo() {{ return {{key:'value'}}; }}
Return object on same line.
JavaScript
age: result name: data,
age: result name: data
Remove comma.
YAML
["test", 9]
["test", 9]
Correct.
JSON
class User {{ int data; }};
class User {{ public: int data; }};
Make public.
C++
.Person {{ color: red; }}
.Person {{ color: red; }}
Correct.
CSS
<a href='https://example.com' target='_blank'>
<a href='https://example.com' target='_blank' rel='noopener'>
Add rel for security.
HTML
let mut b=92; let ref1=&mut b; let ref2=&mut b;
let mut b=92; {{ let ref1=&mut b; }} let ref2=&mut b;
Only one mutable borrow.
Rust
fs.readFile('data.txt', (err,data) => {{ if(err) throw err; }});
fs.readFile('data.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }});
Better error handling.
Node.js
int temp = 'world';
String temp = 'world';
Type mismatch.
Dart
function handle() {{ echo 'result'; }}
function handle() {{ echo 'result'; }}
Correct.
PHP
raise 'world'
raise Exception('world')
Raise needs an exception class.
Python
val y: Int = 'message'
val y: String = 'message'
Fix type.
Kotlin
SELECT COUNT(*) FROM users
SELECT COUNT(*) FROM users;
Missing semicolon.
SQL
[13, 6, 23
[13, 6, 23]
Close bracket.
Ruby
<div color=blue>
<div style='color:blue;'>
Use style attribute.
CSS
if c = 88
if c == 88
Use ==.
MATLAB
const int x; x = 5;
const int x = 5;
Const must be initialized.
C++
z > 55 & x < 38
z > 55 and x < 38
Use 'and' not '&'.
Python
lambda x: x+1
lambda x: x+1
Correct lambda.
Python
SELECT id role FROM users;
SELECT id, role FROM users;
Add comma.
SQL
if (z) console.log('yes') else console.log('no')
if (z) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
DELETE FROM orders WHERE age=30
DELETE FROM orders WHERE age=30;
Add semicolon.
SQL
else print('hello')
else: print('hello')
Colon after else.
Python
let list=vec![24,68,1]; let head=&list[0]; list.push(93);
let mut list=vec![24,68,1]; let head=list[0]; list.push(93);
Copy instead of reference.
Rust
List<int> list = [1,2,3];
List<int> list = [1,2,3];
Correct.
Dart
// comment
/* comment */
Use /* */.
CSS
if (b = 67) {{}}
if (b == 67) {{}}
Use ==.
Java
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
my @arr = (47,78,68);
my @arr = (47,78,68);
Correct.
Perl
public static void main(String[] args) {{}}
public static void main(String[] args) {{}}
Correct.
Java
int* p = nullptr; *p=5;
int* p = new int; *p=5;
Allocate memory.
C++
30item = 10
item30 = 10
Variable cannot start with digit.
Python
String name = 'test';
String name = 'test';
Correct.
Dart
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
System.out.println('info')
System.out.println('info');
Add semicolon.
Java
if (index = 27) {{}}
if (index == 27) {{}}
Use ==.
Java
for i=1,57 do print(i) end
for i=1,57 do print(i) end
Correct.
Lua
if a = 50 then print('value') end
if a == 50 then print('value') end
Use ==.
Lua
console.log('data'
console.log('data')
Close parenthesis.
JavaScript
'9' + 3
9 + 3
Avoid string coercion.
JavaScript
x := 26
x := 26
Correct.
Go
let temp: i32 = "value";
let temp: &str = "value";
Type mismatch.
Rust
let b = 5; b += 1;
let mut b = 5; b += 1;
Need mut to modify.
Rust
for item in range(98) print(item)
for item in range(98): print(item)
Colon after for.
Python
name: data age: 1
name: data age: 1
Correct.
YAML
cin >> z;
int z; cin >> z;
Declare variable.
C++
int main() {{ return 0; }}
int main() {{ return 0; }}
Correct.
C++