Array Pointer

n8grndr1087

Is it possible to set the array pointer to a particular key?

I want to iterate over an array of commands, but some loop commands need to move
the pointer back to a specific key. Iterating with an index variable ($i) would work, but it involves looking up each command.

paulnaj

Quick manual search says no. Wouldn't be hard to create your own class to handle this behaviour though.

n8grndr1087

Thanks. I'm looking for speed here, so if I use an iterator in a class like you said, does PHP anticipate the next element if there is no jump, or does it have to look it up each time?

paulnaj

I think you'd have to be a little more specific about what's actually going on with your 'commands'.

For example, what does-'... looking up each command.' mean?

laserlight

It sounds like n8grndr1087 is coming from a C background where looping through an array with pointers is faster than accessing by index, compiler optimisations aside.

Frankly, in PHP, I do not think that iterators will provide anything more than a negligible speed improvement over accessing an array by index. It might even be a little slower. Chances are the time will be dominated by things like network latency, database and file access, and printing output.

n8grndr1087

sorry about not being clear. i was hoping that PHP would try to optimize sequential array accessing ($a[0], $a[1], $a[2] ...) instead of having to go and find the requested element every time in a for loop.

thank you paulnaj and laserlight.