Understanding defer in Go. Deferred Function Calls A defer statement is an ordinary function or method call prefixed by the keyword defer. The function and argument expressions are evaluated when the statement is executed, but the actual call is def...

Closures and Anonymous Functions in Go. Anonymous Function A function literal is written like a function declaration, but without a name following the func keyword. It is an expression, and its value is called an anonymous function. package main ...

Testing the equivalence of maps in Go. reflect.DeepEqual Function It first checks if both maps are nil, then it checks if they have the same length before finally checking to see if they have the same set of (key, value) pairs. package main impo...

In Golang, there are 2 ways to check string is in json format. Using Unmarshal Function The following example should cover whatever you are trying to do: package main import ( "encoding/json" "fmt" ) func isJson(s string) bool { var js ...

In Golang, using the crypto/aes package is the easiest way to encrypt a string using AES CBC. Ehrsam, Meyer, Smith and Tuchman invented the cipher block chaining (CBC) mode of operation in 1976. In CBC mode, each block of plaintext is XORed with the ...

In Golang, using the crypto/aes package is the easiest way to encrypt a string using AES GCM 256. In cryptography, Galois/Counter Mode (GCM) is a mode of operation for symmetric-key cryptographic block ciphers which is widely adopted for its performa...

In Golang, using the crypto/hmac library is the easiest way to generate a SHA256 HMAC Hash from a string. In cryptography, an HMAC (hash-based message authentication code) is a specific type of message authentication code (MAC) involving a cryptograp...

In PHP, there are 3 ways to delete an element from an array. Using unset Function The unset(mixed $var, mixed ...$vars): void function destroys the specified variables. For example, $arr = ["a", "b", "d"]; unset($arr[1]); print_r($arr); Arr...

In Golang, there are 2 ways to check if a file is a valid image. Using DetectContentType Function The http.DetectContentType() function implements the algorithm described at https://mimesniff.spec.whatwg.org/ to determine the Content-Type of the gi...

In Python, using the os.environ variable is the easiest way to set environment variables Using os.environ Variable os.environ behaves like a python dictionary, so all the common dictionary operations can be performed. In addition to the get and set ...

In Python, there are 3 ways to get key by value in dictionary. Using keys Function Basically, it separates the dictionary's values in a list, finds the position of the value you have, and gets the key at that position. The following example: #!...

In Rust, there are 2 ways to convert float to integer. Using as Keyword Executing an as expression casts the value on the left-hand side to the type on the right-hand side. An example of an as expression: fn main() { let a = 3.6415_f64; l...

In Python, there are 3 ways to return dictionary keys as a list. Using keys Function The dict.keys() function returns a view object that displays a list of all the keys in the dictionary in order of insertion. See the following example: #!/usr/...

In Python, there are 3 ways to remove duplicates in list. Using Built-in set Function The built-in set() function returns a new set object, optionally with elements taken from iterable. If you later need a real list again, you can similarly pass the...

In Golang, using the len function is the easiest way to count the items in the map structure. Using len Function The built-in function len take arguments of various types and return a result of type int. The implementation guarantees that the result...