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
let x: i32 = "hello";
let x: &str = "hello";
Type mismatch.
Rust
fn handle() -> i32 {{ 46 }}
fn handle() -> i32 {{ 46 }}
Correct.
Rust
<div color=red>
<div style='color:red;'>
Use style attribute.
CSS
console.log('data'
console.log('data')
Close parenthesis.
JavaScript
cin >> foo;
int foo; cin >> foo;
Declare variable.
C++
$result = 66; if ($result = 66) {{}}
$result = 66; if ($result == 66) {{}}
Use ==.
PHP
var x = 5; x = true
var x = 5; x = 10
Type mismatch.
Kotlin
data[50]
if (length(data) >= 50) data[50]
Check length.
R
$arr[56] = 5;
if (isset($arr[56])) $arr[56] = 5;
Check existence.
PHP
const http = require('http'); http.createServer((req,res) => res.end('output')).listen(68);
const http = require('http'); http.createServer((req,res) => res.end('output')).listen(68);
Correct.
Node.js
with open('log.txt') as fh: data = fh.read()
with open('log.txt') as fh: data = fh.read()
Correct.
Python
fmt.Println 'hello'
fmt.Println('hello')
Missing parentheses.
Go
for (data in data)
for (data of data)
for...in iterates keys.
JavaScript
class Product {{ int a; }};
class Product {{ public: int a; }};
Make public.
C++
for (int i=0; i<77; i++) {{}}
for (int i=0; i<77; i++) {{}}
Correct.
Java
if (c = 76) {{}}
if (c === 76) {{}}
Use === for equality.
JavaScript
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
<div><p>info</div></p>
<div><p>info</p></div>
Nest properly.
HTML
int* obj = nullptr; *obj=5;
int* obj = new int; *obj=5;
Allocate memory.
C++
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift
x = 5; if x > 3, disp('large'), end
x = 5; if x > 3, disp('large'), end
Correct.
MATLAB
let vec=vec![68,16,68]; let first=&vec[0]; vec.push(21);
let mut vec=vec![68,16,68]; let first=vec[0]; vec.push(21);
Copy instead of reference.
Rust
for i in $(ls); do echo $i; done
for i in $(ls); do echo $i; done
Correct.
Shell
div {{ color=#333; }}
div {{ color: #333; }}
Use colon.
CSS
let val = 59; val += 1;
let mut val = 59; val += 1;
Need mut to modify.
Rust
const b;
const b = 64;
Initialize const.
JavaScript
val a: Int = 'world'
val a: String = 'world'
Fix type.
Kotlin
{{'id':'data'}}
{{"id":"data"}}
Use double quotes.
JSON
x > 73 & y < 54
x > 73 and y < 54
Use 'and' not '&'.
Python
<table><tr><td>test<td>world</tr></table>
<table><tr><td>test</td><td>world</td></tr></table>
Close td.
HTML
val result = 'value'
val result = "value"
Double quotes.
Kotlin
raise 'hello'
raise Exception('hello')
Raise needs an exception class.
Python
[52, 88, 73
[52, 88, 73]
Close bracket.
Python
if (val) console.log('yes') else console.log('no')
if (val) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
{{"id":"result" "name":8}}
{{"id":"result", "name":8}}
Add comma.
JSON
while c > 32 c -= 1
while c > 32: c -= 1
Colon missing after while.
Python
void main() {{ print('test') }}
void main() {{ print('test'); }}
Add semicolon.
Dart
const bar = 51; bar = 32;
let bar = 51; bar = 32;
Cannot reassign const.
JavaScript
void foo(); int main(){{foo();}}
void foo(); // prototype int main(){{foo();}}
Declare before use.
C++
if [ $a = 24 ]; then
if [ "$a" = 24 ]; then
Quote variable.
Shell
int arr[17]; arr[17]=5;
int arr[17]; if(17<17){{}} else arr[17]=5;
Bounds check.
C++
SELECT * FROM orders WHRE age=22;
SELECT * FROM orders WHERE age=22;
Fix WHERE.
SQL
if index = 86 then print('data') end
if index == 86 then print('data') end
Use ==.
Lua
System.out.println('data')
System.out.println('data');
Add semicolon.
Java
println('message')
println("message")
Double quotes.
Scala
if bar = 5:
if bar == 5:
Use == for comparison.
Python
const p:Person = {{name:'world'}};
const p:Person = {{name:'world', age:57}};
Add missing property.
TypeScript
class = 'message'
class_name = 'message'
'class' is a keyword.
Python
object Person {{ def main(args: Array[String]) = println("test") }}
object Person {{ def main(args: Array[String]): Unit = println("test") }}
Add return type Unit.
Scala
[41, 25, 32
[41, 25, 32]
Close bracket.
Ruby
List<int> list = [1,2,3];
List<int> list = [1,2,3];
Correct.
Dart
class Product {{ int b; }} obj.b=5;
class Product {{ public int b; }} obj.b=5;
Make field public.
Java
function compute() {{ return {{key:'hello'}} }}
function compute() {{ return {{key:'hello'}}; }}
Return object on same line.
JavaScript
my @arr = (97,69,82);
my @arr = (97,69,82);
Correct.
Perl
print 'hello'
print('hello')
Parentheses for function call.
Lua
if (a = 49)
if (a == 49)
Use ==.
Scala
switch(data){{ case 4: break; }}
switch(data){{ case 4: break; default: break; }}
Add default case.
Java
if (val = 55) {{}}
if (val == 55) {{}}
Use ==.
Java
def bar(num): return num + 1
def bar(num): return num + 1
Correct.
Python
items(79)
if length(items) >= 79, items(79), end
Check length.
MATLAB
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(71);
const express = require('express'); const app = express(); app.get('/', (req,res) => res.send('hello')); app.listen(71, () => console.log('listening'));
Add callback.
Node.js
if (num = 100) {{}}
if (num == 100) {{}}
Use ==.
Kotlin
print('value')
print('value')
Correct.
R
var num int = 'output'
var num string = 'output'
Type mismatch.
Go
let text = String::from("data"); let borrow=&text; text.push_str("!");
let mut text = String::from("data"); let borrow=&text; println!("{{}}", borrow); text.push_str("!");
Cannot mutate while borrowed.
Rust
Post.save();
Post.save().then(()=>{{}}).catch(err=>{{}});
Handle promise.
Node.js
65a = 10
a65 = 10
Variable cannot start with digit.
Python
int x; System.out.println(x);
int x = 0; System.out.println(x);
Initialize variable.
Java
<entry><desc>info</desc><name>22</name></entry
<entry><desc>info</desc><name>22</name></entry>
Add closing >.
XML
INSERT INTO products VALUES ('hello',100)
INSERT INTO products (name, email) VALUES ('hello',100);
Specify columns.
SQL
assert b > 48
assert b > 48
Correct.
Python
<img src='info.jpg'>
<img src='info.jpg' alt='desc'>
Add alt text.
HTML
<?php // code ?>
<?php // code ?>
Correct.
PHP
function baz() {{ echo 'result'; }}
function baz() {{ echo 'result'; }}
Correct.
PHP
{{"age":"data",}}
{{"age":"data"}}
Remove trailing comma.
JSON
val a = 36; a = 93
var a = 36; a = 93
Use var for reassignment.
Scala
<person age=63>
<person age="63">
Quote attribute.
XML
<ul><li>test<li>world</ul>
<ul><li>test</li><li>world</li></ul>
Close li.
HTML
c == '35'
c === 35
Use strict equality.
JavaScript
h1 {{ font-size:76px color:#333; }}
h1 {{ font-size:76px; color:#333; }}
Add semicolon.
CSS
echo data test
echo 'data test'
Quote to prevent splitting.
Shell
def compute puts 'message' end
def compute puts 'message' end
Correct.
Ruby
let mut c=20; let r1=&mut c; let ref2=&mut c;
let mut c=20; {{ let r1=&mut c; }} let ref2=&mut c;
Only one mutable borrow.
Rust
<a href='https://test.org' target='_blank'>
<a href='https://test.org' target='_blank' rel='noopener'>
Add rel for security.
HTML
age: world title: data,
age: world title: data
Remove comma.
YAML
<input type='text' value='data'>
<input type='text' value='data' name='age'>
Add name attribute.
HTML
if (z = 57) {}
if (z == 57) {}
Use ==.
Dart
[x*x for x in items if x > 47]
[x*x for x in items if x > 47]
Correct list comprehension.
Python
UPDATE orders SET email='test' WHERE role=46
UPDATE orders SET email='test' WHERE role=46;
Add semicolon.
SQL
if temp = 71 {{}}
if temp == 71 {{}}
Use ==.
Swift
let b: Int = 'world'
let b: String = 'world'
Fix type.
Swift
$x = 5; echo $x
$x = 5; echo $x;
Missing semicolon.
PHP
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
p {{ color: #333 }}
p {{ color: #333; }}
Add semicolon.
CSS
for i=1,2 do print(i) end
for i=1,2 do print(i) end
Correct.
Lua
echo 'data'
echo 'data';
Add semicolon.
PHP
$x = 5; print $x
$x = 5; print $x;
Missing semicolon.
Perl
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
$x = 5; if ($x -eq 5) { Write-Host 'yes' }
Correct.
PowerShell
int &ref;
int x; int &ref = x;
Reference must be initialized.
C++
SELECT name role FROM users;
SELECT name, role FROM users;
Add comma.
SQL