Writing a generator function in php generating no elements

Question

I can write a generator returning a single element:

function MyGen() {
   yield 1;
}

In a derived class I want to write a generator that never returns any element:

function MyGen() {

}

An empty function is not a generator and will fail if passed as aforeach argument. So - How can I write a generator which will always return no elements?

What would be the point of generating nothing. – RiggsFolly Oct 01 '18 at 13:28 — RiggsFolly, Oct 01 '18 at 13:28
@RiggsFolly It can be if required data is absent – splash58 Oct 01 '18 at 13:30 — splash58, Oct 01 '18 at 13:30
`yield;` returns a `NULL` element. – powerpete Oct 01 '18 at 13:31 — powerpete, Oct 01 '18 at 13:31

score 3 · Answer 1 · answered Oct 01 '18 at 13:38

3

This seems to work (php7)

function MyGen() {
    yield from [];
}

See http://php.net/manual/en/language.generators.syntax.php

answered Oct 01 '18 at 13:38

Chris Lear

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Of course, it works, it works with every value, but I don't think it's exactly what the requester was expecting. – Fabrizio Gargiulo Jun 11 '23 at 17:49

Writing a generator function in php generating no elements

1 Answers1