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 result = 5; result += 1;
let mut result = 5; result += 1;
Need mut to modify.
Rust
int &ref;
int x; int &ref = x;
Reference must be initialized.
C++
.User {{ color: #333; }}
.User {{ color: #333; }}
Correct.
CSS
for z in range(52) print(z)
for z in range(52): print(z)
Colon after for.
Python
name: message age: 47
name: message age: 47
Correct.
YAML
ArrayList list = new ArrayList();
ArrayList<String> list = new ArrayList<>();
Use generics.
Java
int list[38]; list[38]=5;
int list[38]; if(38<38){{}} else list[38]=5;
Bounds check.
C++
my @arr = (1,19,41);
my @arr = (1,19,41);
Correct.
Perl
var x = 5; x = "hello"
var x = "hello"
Type mismatch.
Swift
if (bar) console.log('yes') else console.log('no')
if (bar) console.log('yes'); else console.log('no');
Missing semicolon.
JavaScript
for (int i=0; i<8; i++) {{}}
for (int i=0; i<8; i++) {{}}
Correct.
Java
[21, 28, 50
[21, 28, 50]
Close bracket.
Python
WHERE age = '55'
WHERE age = 55
Don't quote integer.
SQL
[47, 78, 74
[47, 78, 74]
Close bracket.
Ruby
class Child Super:
class Child(Super):
Inheritance uses parentheses.
Python
$list[68]
if ($list.Count -gt 68) {{ $list[68] }}
Check bounds.
PowerShell
let temp = 100;
let temp = 100;
Correct.
JavaScript
echo 'output'
echo 'output';
Add semicolon.
PHP
raise 'test'
raise Exception('test')
Raise needs an exception class.
Python
let count: number = 'value';
let count: string = 'value';
Fix type.
TypeScript
class = 'result'
class_name = 'result'
'class' is a keyword.
Python
for (item in items)
for (item of items)
for...in iterates keys.
JavaScript
if data > 89 print('output')
if data > 89: print('output')
Colon missing after if.
Python
System.out.println('data')
System.out.println('data');
Add semicolon.
Java
val a: Int = 'test'
val a: String = 'test'
Fix type.
Kotlin
echo result hello
echo 'result hello'
Quote to prevent splitting.
Shell
let temp: i32 = "hello";
let temp: &str = "hello";
Type mismatch.
Rust
console.log('message'
console.log('message')
Close parenthesis.
JavaScript
yield item
yield item
Correct yield.
Python
{{'id':'world'}}
{{"id":"world"}}
Use double quotes.
JSON
println('info')
println("info")
Double quotes.
Scala
var x = 69;
var x = 69;
Correct.
Dart
local index = 14
local index = 14
Correct.
Lua
void main() {{ print('test') }}
void main() {{ print('test'); }}
Add semicolon.
Dart
print 'hello'
print('hello')
Parentheses for function call.
Lua
match index {{ 1 => {{}} }}
match index {{ 1 => {{}} _ => {{}} }}
Match must be exhaustive.
Rust
foo
foo()
Add parentheses.
Kotlin
[x*x for x in values if x > 5]
[x*x for x in values if x > 5]
Correct list comprehension.
Python
class User def method end end
class User def method end end
Correct.
Ruby
while num > 92 num -= 1
while num > 92: num -= 1
Colon missing after while.
Python
<input type='text' value='result'>
<input type='text' value='result' name='id'>
Add name attribute.
HTML
Write-Host 'info'
Write-Host 'info'
Correct.
PowerShell
<div><p>value</div></p>
<div><p>value</p></div>
Nest properly.
HTML
print('test')
print('test')
Correct.
R
if temp > 73 puts 'test'
if temp > 73 puts 'test' end
Add 'end'.
Ruby
SELECT COUNT(*) FROM users
SELECT COUNT(*) FROM users;
Missing semicolon.
SQL
int* obj = nullptr; *obj=5;
int* obj = new int; *obj=5;
Allocate memory.
C++
// comment
/* comment */
Use /* */.
CSS
h1 {{ font-size:58px color:green; }}
h1 {{ font-size:58px; color:green; }}
Add semicolon.
CSS
b == '90'
b === 90
Use strict equality.
JavaScript
INSERT INTO items VALUES ('hello',10)
INSERT INTO items (age, role) VALUES ('hello',10);
Specify columns.
SQL
if (num = 75)
if (num == 75)
Use ==.
R
let vec=vec![45,62,48]; let first=&vec[0]; vec.push(69);
let mut vec=vec![45,62,48]; let first=vec[0]; vec.push(69);
Copy instead of reference.
Rust
b > 100 & z < 53
b > 100 and z < 53
Use 'and' not '&'.
Python
fn render() -> i32 {{ 81 }}
fn render() -> i32 {{ 81 }}
Correct.
Rust
function bar(index) print(index) end
function bar(index) print(index) end
Correct.
Lua
function render(): void {{ return 25; }}
function render(): number {{ return 25; }}
Return type mismatch.
TypeScript
<ul><li>test<li>data</ul>
<ul><li>test</li><li>data</li></ul>
Close li.
HTML
<img src='test.jpg'>
<img src='test.jpg' alt='desc'>
Add alt text.
HTML
val a = 67; a = 37
var a = 67; a = 37
Use var for reassignment.
Scala
77val = 10
val77 = 10
Variable cannot start with digit.
Python
let text1 = String::from("hello"); let str2 = text1; println!("{{}}", text1);
let text1 = String::from("hello"); let str2 = text1.clone(); println!("{{}}", text1);
Clone to avoid move.
Rust
if result = 58 {{}}
if result == 58 {{}}
Use ==.
Swift
{{'status':20, 'value' 38}}
{{'status':20, 'value':38}}
Colon missing.
Python
let c = 99; let c = 91;
let c = 99; c = 91;
Duplicate declaration.
JavaScript
arr[19]
if (length(arr) >= 19) arr[19]
Check length.
R
let item: Int = 'output'
let item: String = 'output'
Fix type.
Swift
while read line; do echo $line; done < input.csv
while read line; do echo $line; done < input.csv
Correct.
Shell
function process() {{ echo 'info'; }}
function process() {{ echo 'info'; }}
Correct.
PHP
<center>world</center>
<div style='text-align:center;'>world</div>
Use CSS.
HTML
if index = 15:
if index == 15:
Use == for comparison.
Python
<person name='output'/>
<person name="output"/>
Double quotes.
XML
object Product {{ def main(args: Array[String]) = println("test") }}
object Product {{ def main(args: Array[String]): Unit = println("test") }}
Add return type Unit.
Scala
cin >> val cout << val;
cin >> val; cout << val;
Add semicolon.
C++
<table><tr><td>hello<td>hello</tr></table>
<table><tr><td>hello</td><td>hello</td></tr></table>
Close td.
HTML
const result = 51; result = 40;
let result = 51; result = 40;
Cannot reassign const.
JavaScript
function compute(result:string){{return result;}} compute(24);
function compute(result:string){{return result;}} compute('world');
Pass correct type.
TypeScript
let data = 'data'
let data = "data"
Double quotes.
Swift
if ($c = 95)
if ($c == 95)
Use ==.
Perl
lambda x: x+1
lambda x: x+1
Correct lambda.
Python
List<int> list = [1,2,3];
List<int> list = [1,2,3];
Correct.
Dart
<br></br>
<br>
Self-closing.
HTML
$x = 5; print $x
$x = 5; print $x;
Missing semicolon.
Perl
list[94]
if (list.indices.contains(94)) list[94]
Check index.
Kotlin
void compute(); int main(){{compute();}}
void compute(); // prototype int main(){{compute();}}
Declare before use.
C++
fs.readFile('log.txt', (err,data) => {{ if(err) throw err; }});
fs.readFile('log.txt', (err,data) => {{ if(err) {{ console.error(err); return; }} }});
Better error handling.
Node.js
SELECT name email FROM items;
SELECT name, email FROM items;
Add comma.
SQL
foo = output
foo = 'output'
Quote strings.
Python
<hr></hr>
<hr>
Self-closing.
HTML
const obj:Person = {{name:'result'}};
const obj:Person = {{name:'result', age:34}};
Add missing property.
TypeScript
'63' + 99
63 + 99
Avoid string coercion.
JavaScript
with open('data.txt') as fh: data = fh.read()
with open('data.txt') as fh: data = fh.read()
Correct.
Python
{ "name": "message" }
{ "name": "message" }
Correct.
JSON
x := 36
x := 36
Correct.
Go
#footer {{ color: #333; }}
#footer {{ color: #333; }}
Correct.
CSS
String name = 'output';
String name = 'output';
Correct.
Dart
'result' + 55
'result' + str(55)
Can't add int to string.
Python
else print('message')
else: print('message')
Colon after else.
Python
let y: number | null = null; y.toFixed(100);
let y: number | null = null; if(y!==null) y.toFixed(100);
Null check.
TypeScript
$x = 5; echo $x
$x = 5; echo $x;
Missing semicolon.
PHP