Hello All,
I just want to bring in a different perception on the proposed
feature. I think people are very focused on what I call "library
code". This is the kind of code that should in theory be worked on
less, than the glue code that you write in every project to finish up
the applications your customers have requested.
IMHO type hinting and more importantly strict type hinting is very
focused with making the life of library developers easier. They can
just easily discard anything that doesnt match their expectations
100%. That this is not how PHP has traditionally worked has been
mentioned quite often in this thread. But I want to direct peoples
attention to the code that calls strictly typed libraries.
Suddenly I need to ensure that all my variables have the proper types.
So what will people do? They will start forcing type juggeling
manually before they call the library in question. Since this is the
glue code, its the kind of code you have to write day in day out. So
maybe an "(int)" here or there is not so much more code to type, but
you can already see that code you safe on one end, you have to start
adding on the other, the one which you write more often. More
importantly, in some cases simple type juggeling with "(int)" will not
be sufficient, you might have to do some minor checks etc. In the past
library authors did this as part of the code that the strict type
hinting camp is now hoping to remove. So again more code in my glue
code.
Furthermore people over estimate the usefulness of automated errors.
They tend to include very minimal context information. So when in the
past people had to write out the parameter checking code manually,
they had the opportunity to very easily add important context
information to whatever error they raised. This will no longer be the
case with strict type hinting. There it will be the responsibility for
the caller to make sense of the error and know whatever context is
relevant for this error condition.
I guess the reply I can expect from this mail is that I do not have to
use it, that I do not have to use libraries that use strict type
hinting or that good developers will pick and choose when to use
strict type hinting. While this may be true, we do not live in a
perfect world. So again I want to remind people that as we develop the
language, we need to pick and choose what features come in that will
ensure that PHP remains at least as productive has it has been in the
past for its users.
As such I want to again bring up that a loose type hinting with types
like "scalar" and "numeric" are much less risky, since they are a much
wider filter. Its quite easy to figure out why a function that is
documented to not operate on arrays to come back with an error when I
pass it an array. However it will be a bit confusing to get an error
when I pass '1' to a method that then comes back to complain I did not
pass an integer.
regards,
Lukas
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
