include vs. require

[mrjam]

Call me stupid (once is enough thank you), but I just can't seem to understand the differences between include(once) and require(once).

I'm currently using include on a project I'm working, so I know how that works. But the difference...

I have read manuals on php.net, but I just cant get it into my head. I think that maybe some old programming skills causes me not to understand it. Some very basic ideas/examples would be grateful please.

Thanks in advance.

// Thomasson

[khaine]

The only info I could find to distiguise between the two is

require() is not actually a function in PHP; rather, it is a language construct. It is subject to some different rules than functions are. For instance, require() is not subject to any containing control structures. For another, it does not return any value; attempting to read a return value from a require() call results in a parse error.

and

include() differs from require() in that the include statement is re-evaluated each time it is encountered (and only when it is being executed), whereas the require() statement is replaced by the required file when it is first encountered, whether the contents of the file will be evaluated or not (for example, if it is inside an if statement whose condition evaluated to false).

I think basically that if you have an include in an if statment it will reduce to processing time because it is not included. wereas if the include was replaced with a require the file would be included even if it was never run.

Mark.