Edd Mann has a new post today sharing some of his exploration into implementing tuples in PHP. A tuple is a common data structure in other languages consisting of an immutable, ordered list of items.

Since exploring languages such as Scala and Python which provide the tuple data-structure, I have been keen to experiment with how to clearly map it into a PHP solution. Tuples are simply a finite, ordered sequence of elements - usually with good language support to both pack (construction) and unpack (deconstruction) of the values. I have found that many use-cases of the common place array structure in PHP could be better suited to n-tuple's. [...] I discussed briefly that what makes tuples so powerful in the highlighted languages is their good support for handling their contents, for example unpacking a user tuple into separate id and name variables. PHP supports this form of unpacking in regard to arrays using the 'list' function, which I frequently use to return multiple values from a function/method invocation.

He shares the code for his basic implementation, extended from the SplFixedArray, and shows an example of it in use. He also includes samples showing how to make typed tuples via a "type" method call.