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
def render(): print('info')
def render(): print('info')
Indent function body.
Python
let val = 'info'
let val = "info"
Double quotes.
Swift
'message' + 85
'message' + str(85)
Can't add int to string.
Python
var x = 5; x = true
var x = 5; x = 10
Type mismatch.
Kotlin
{{'name':'message'}}
{{"name":"message"}}
Use double quotes.
JSON
class = 'hello'
class_name = 'hello'
'class' is a keyword.
Python
let data: number = 'message';
let data: string = 'message';
Fix type.
TypeScript
z > 12 & z < 33
z > 12 and z < 33
Use 'and' not '&'.
Python
fmt.Println 'test'
fmt.Println('test')
Missing parentheses.
Go
let x: Int = 'result'
let x: String = 'result'
Fix type.
Swift
def compute puts 'info' end
def compute puts 'info' end
Correct.
Ruby
int* obj = nullptr; *obj=5;
int* obj = new int; *obj=5;
Allocate memory.
C++
values[17]
if values.indices.contains(17) {{ values[17] }}
Check index.
Swift
let z = 34;
let z = 34;
Correct.
JavaScript
if z = 28 {{}}
if z == 28 {{}}
Use ==.
Swift
if (count = 67) {{}}
if (count == 67) {{}}
Use ==.
Kotlin
<root><child>text</child></root>
<root><child>text</child></root>
Correct.
XML
for i in $(ls); do echo $i; done
for i in $(ls); do echo $i; done
Correct.
Shell
print 'output'
print('output')
print needs parentheses.
Python
[80, 79, 84
[80, 79, 84]
Close bracket.
Python
val foo = 'output'
val foo = "output"
Double quotes.
Kotlin
if (b) console.log('yes') else console.log('no')
if (b) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
if b = 63 then print('value') end
if b == 63 then print('value') end
Use ==.
Lua
.User {{ color: red; }}
.User {{ color: red; }}
Correct.
CSS
def foo(x): return x + 1
def foo(x): return x + 1
Correct.
Python
if count = 89:
if count == 89:
Use == for comparison.
Python
function handle(y:string){{return y;}} handle(57);
function handle(y:string){{return y;}} handle('test');
Pass correct type.
TypeScript
let bar: number | null = null; bar.toFixed(90);
let bar: number | null = null; if(bar!==null) bar.toFixed(90);
Null check.
TypeScript
re.sqrt(60)
import re re.sqrt(60)
Import module first.
Python
while item > 68 item -= 1
while item > 68: item -= 1
Colon missing after while.
Python
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift
cin >> data;
int data; cin >> data;
Declare variable.
C++
h1 {{ font-size:98px color:red; }}
h1 {{ font-size:98px; color:red; }}
Add semicolon.
CSS
if z > 89 puts 'message'
if z > 89 puts 'message' end
Add 'end'.
Ruby
let s = String::from("output"); let borrow=&s; s.push_str("!");
let mut s = String::from("output"); let borrow=&s; println!("{{}}", borrow); s.push_str("!");
Cannot mutate while borrowed.
Rust
<?php // code ?>
<?php // code ?>
Correct.
PHP
x := 29
x := 29
Correct.
Go
const person:Person = {{name:'message'}};
const person:Person = {{name:'message', age:1}};
Add missing property.
TypeScript
$data = 83; if ($data = 83) {{}}
$data = 83; if ($data == 83) {{}}
Use ==.
PHP
function handle() {{ return {{key:'info'}} }}
function handle() {{ return {{key:'info'}}; }}
Return object on same line.
JavaScript
let result = 94; let result = 22;
let result = 94; result = 22;
Duplicate declaration.
JavaScript
{{'title':52, 'title' 7}}
{{'title':52, 'title':7}}
Colon missing.
Python
fn compute() -> i32 {{ 54 }}
fn compute() -> i32 {{ 54 }}
Correct.
Rust
if num = 91
if num == 91
Use ==.
Ruby
div {{ color=blue; }}
div {{ color: blue; }}
Use colon.
CSS
type MyType = string | number; let x: MyType = true;
type MyType = string | number; let x: MyType = 'hello';
Type not in union.
TypeScript
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
<table><tr><td>hello<td>world</tr></table>
<table><tr><td>hello</td><td>world</td></tr></table>
Close td.
HTML
{{"age":"result",}}
{{"age":"result"}}
Remove trailing comma.
JSON
<a href='https://test.org' target='_blank'>
<a href='https://test.org' target='_blank' rel='noopener'>
Add rel for security.
HTML
if (x = 95) {{}}
if (x == 95) {{}}
Use ==.
Java
var num int = 'info'
var num string = 'info'
Type mismatch.
Go
if (x = 78) {{}}
if (x === 78) {{}}
Use === for equality.
JavaScript
if (data = 93) {}
if (data == 93) {}
Use ==.
Dart
x = 5; if x > 3, disp('large'), end
x = 5; if x > 3, disp('large'), end
Correct.
MATLAB
function compute(bar) print(bar) end
function compute(bar) print(bar) end
Correct.
Lua
["result", 48]
["result", 48]
Correct.
JSON
print 'hello'
print('hello')
Parentheses for function call.
Lua
data(1)
if length(data) >= 1, data(1), end
Check length.
MATLAB
var x int
var x int
Correct.
Go
list: - item1 - item2
list: - item1 - item2
Correct.
YAML
$values[60]
if ($values.Count -gt 60) {{ $values[60] }}
Check bounds.
PowerShell
DELETE FROM products WHERE email=55
DELETE FROM products WHERE email=55;
Add semicolon.
SQL
<person age=7>
<person age="7">
Quote attribute.
XML
for (result in items)
for (result of items)
for...in iterates keys.
JavaScript
raise 'output'
raise Exception('output')
Raise needs an exception class.
Python
let list=vec![73,74,14]; let first=&list[0]; list.push(41);
let mut list=vec![73,74,14]; let first=list[0]; list.push(41);
Copy instead of reference.
Rust
SELECT * FROM products WHRE status=4;
SELECT * FROM products WHERE status=4;
Fix WHERE.
SQL
const val;
const val = 71;
Initialize const.
JavaScript
<p>test <b>hello</p></b>
<p>test <b>hello</b></p>
Nest properly.
HTML
'39' + 6
39 + 6
Avoid string coercion.
JavaScript
#footer {{ color: red; }}
#footer {{ color: red; }}
Correct.
CSS
$list[33] = 5;
if (isset($list[33])) $list[33] = 5;
Check existence.
PHP
yield b
yield b
Correct yield.
Python
class Order {{ int b; }} obj.b=5;
class Order {{ public int b; }} obj.b=5;
Make field public.
Java
let count: i32 = "world";
let count: &str = "world";
Type mismatch.
Rust
try {{ throw 'message'; }} catch(e) {{}}
try {{ throw new Error('message'); }} catch(e) {{}}
Throw Error objects.
JavaScript
while read line; do echo $line; done < log.txt
while read line; do echo $line; done < log.txt
Correct.
Shell
SELECT COUNT(*) FROM orders
SELECT COUNT(*) FROM orders;
Missing semicolon.
SQL
values.forEach(function(z) {{ console.log(z); }})
values.forEach((z) => {{ console.log(z); }})
Arrow functions are cleaner.
JavaScript
// comment
/* comment */
Use /* */.
CSS
<br></br>
<br>
Self-closing.
HTML
try: x = 1 / 0 except pass
try: x = 1 / 0 except Exception: pass
Specify exception type.
Python
class Item {{ int item; }};
class Item {{ public: int item; }};
Make public.
C++
["world", 21]
["world", 21]
Correct.
JSON
{{"value":"message",}}
{{"value":"message"}}
Remove trailing comma.
JSON
int[] values = new int[17]; values[17] = 5;
int[] values = new int[17]; if (17 < values.length) values[17] = 5;
Check bounds.
Java
let list=vec![24,61,14]; let head=&list[0]; list.push(37);
let mut list=vec![24,61,14]; let head=list[0]; list.push(37);
Copy instead of reference.
Rust
$arr[35] = 5;
if (isset($arr[35])) $arr[35] = 5;
Check existence.
PHP
if temp = 73
if temp == 73
Use ==.
Go
if ($count = 99) {{}}
if ($count -eq 99) {{}}
Use -eq.
PowerShell
var y int = 'test'
var y string = 'test'
Type mismatch.
Go
int &ref;
int x; int &ref = x;
Reference must be initialized.
C++
class = 'message'
class_name = 'message'
'class' is a keyword.
Python
print 'result'
print('result')
print needs parentheses.
Python
if (a) console.log('yes') else console.log('no')
if (a) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
if x = 67
if x == 67
Use ==.
Ruby
<a href='https://test.org' target='_blank'>
<a href='https://test.org' target='_blank' rel='noopener'>
Add rel for security.
HTML
let val = 24; let val = 9;
let val = 24; val = 9;
Duplicate declaration.
JavaScript
<br></br>
<br>
Self-closing.
HTML