Why do some PHP programmers use a double backslash in their namespaces instead of a single one?

Question

While scanning some library code today, I've seen it several times: Instead of declaring a NamespaceLikeThis, it's Done\Like\This.

Could somebody please enlighten me – whats the reason behind this?

All I can images that it's either something framework specific (which I don't believe), or it's a strange form of escaping that I don't understand.

Answer 1

You should use double backslash when you're referencing the class name in a string, eg: $className = "Foo\Bar". This is prevent the escaping of characters, a familiar example would be a newline echo "Hello World "; If you had two backslashes it would print "Hello World " rather than "Hello World" with a new line.