Re: [RFC] Context Managers, v2

On Thu, 5 Nov 2026 at 19:33, Larry Garfield <larry@garfieldtech.com> wrote: > On Thu, Nov 5, 2026, at 12:18 PM, Stephen Reay wrote: > > > > > Hi Larry, > > > > TLDR: why => rather than > > as? > > > > As a userland developer I like what this is trying to achieve. I'm not > > knowledgeable enough about the internals to comment on the finer > > details or their ramifications - I just have a bike shedding > > suggestion/question which seemed glaring to me so I wonder if it's > > because of an ambiguous syntax or some other issue? > > > > The => symbol seems odd to me, given how it's used > > elsewhere > > (generally as an indicator of a key/value pair, whether in an array or > > match block) and how generators/iterables are used elsewhere (ie > > foreach as) > > > > Your example is: > > > > using (file_for_write('file.txt') => $fp) { > > > > Whereas to my eye this seems like a much more obvious choice: > > > > using (file_for_write('file.txt') as $fp) { > > > > Anyway, just a thought. > > The v1 RFC originally used as, which is what Python uses as > well. > However, a lot of people were concerned that it implied that the left side > expression would be "used as" the right side variable. While in some cases > it might be, the typical case is that it's not. The context variable is > emitted by the context manager, but is not the same thing. > > At the time, no one could really agree on a better keyword. But => was > right there waiting to be used, and already has an "evaluates to" or > "yields" or "produces" meaning, which is roughly accurate to what happens > here. > > I don't mind as, personally, but the consensus before > seemed to not care > for it. > > --Larry Garfield > Hello Larry, Using the => operator for this case looks inconsistent to me as well. In my perception, the meaning of => in PHP is that of mapping as a function in the mathematical sense: the domain mapped to the image. For example, we have keys mapped to values in arrays or in yield generators or even in iterations with foreach. Similarly, the usage of => in lambda functions is also consistent as we have a mapping of input to output. In this new case, however, it looks like it is used more as an assignment. In the statement foreach ($iterable as $key => $value), the assignment operator is as, while => consistently carries the meaning of a map. So, I would argue that using as for assigning is more consistent with the previous syntax choices. Lazare INEPOLOGLOU Architecte Logiciel