PHP Double Equals == equality chart: PHP Triple Equals === Equality chart: Source code to create these images: PHP equality charts Guru Meditation Those who wish to keep their sanity, read no further because none of this will make any sense, except to say that this is how the insanity-fractal, of PHP was designed. NAN != NAN but NAN == true.
Note that the ; is redundant; as the answers suggest this short-tag expands to an echo with a semicolon added to the end, as per the php documents.
When your first argument is null, they're basically the same except that the null coalescing won't output an E_NOTICE when you have an undefined variable. The PHP 7.0 migration docs has this to say: The null coalescing operator (??) has been added as syntactic sugar for the common case of needing to use a ternary in conjunction with isset (). It returns its first operand if it exists and is ...
In PHP, with systems where a user can login, it is not uncommon for an administrator to be able to impersonate another user for testing purposes. With the above example, if the user is not impersonating another user, and also a logged in user does not exist, then the user will be a guest user instead. Read on more if you don't understand this yet to see what ternaries are and how they are used ...
I've been dabbling with PHP/MySQL for a few years now and even wrote a very basic CMS for my website at one point. However, I learned as I went and never picked up any formal programming structure or ...