Python

To join an array (or list) of strings into one string in Python, you can use the join() method. This method is called on a string that acts as a separator and takes an iterable (like a list) as its argument. The elements of the iterable are then concatenated into a single string, with the separator string placed between each element.

var1 = ['devlabs', '.', 'ninja', '!']
result = ''.join(var1)
print(result)  # Output: devlabs.ninja!

In this example, '' (an empty string) is used as the separator, meaning the elements will be joined without any character between them. You can use any string as the separator, including spaces, commas, or even special characters.

The join() method is efficient and considered Pythonic for combining a list of strings into a single string. It's worth noting that join() can only be used with iterables containing strings. If you attempt to use it with a list that contains non-string elements, you'll encounter a TypeError. To work around this, you can convert each element to a string before joining them, using a generator expression or a list comprehension:

numbers = [1,  2,  3,  4,  5]
result = ', '.join(str(number) for number in numbers)
print(result)  # Output:  1,  2,  3,  4,  5

Java

Using Java Streams: With Java 8 and above, you can use the Stream API to convert a list of strings into a comma-separated string. The Collectors.joining() method is used to join the elements of the stream with a specified delimiter.

List<String> list = Arrays.asList("ONE", "TWO", "THREE");
String commaSeparatedString = list.stream().collect(Collectors.joining(","));
System.out.println(commaSeparatedString); // Output: ONE,TWO,THREE

Using String.join() Method: This is a straightforward approach using the join() method from the String class. It takes two parameters: the delimiter (in this case, a comma) and the list of strings to join.

List<String> list = Arrays.asList("ONE", "TWO", "THREE");
String commaSeparatedString = String.join(",", list);
System.out.println(commaSeparatedString); // Output: ONE,TWO,THREE

JavaScript / TypeScript

Similar to Java, you can use the join method of arrays to combine strings:

const words = ["Hello", "world", "this", "is", "JavaScript"];
const sentence = words.join(" ");
console.log(sentence); // Output: "Hello world this is JavaScript"

PHP

In PHP, the equivalent function is implode. This function works similarly to join in JavaScript, combining array elements into a single string.

<?php
$words = ["Hello", "world", "this", "is", "PHP"];
$sentence = implode(" ", $words);
echo $sentence; // Output: "Hello world this is PHP"
?>