In a message dated Wed, 4 Oct 2006, chromatic writes:
The assumption I remember from the design meetings was always "No library
designer has the knowledge or the right to tell me how fast or strict my
program has to run." Whatever B&D you do in the privacy of your own modules
is fine, but if it leaks out past encapsulation boundaries, expect that
somewhere you might offend community standards.
Yes, but by the same token, no library designer should force you to be
*less* strict than you wish to. I remember not so many years ago when
there were a lot of modules floating around that required you to do "no
strict" of various flavors in order to use them. I still run across
modules that need "no warnings". (I won't name names, because some of
their authors post to this list ;)
It should at the very least be *possible* to write modules that can be
used in every level of strictness from one-liners to
every-possible-stricture, everything-typed, everything-contracted systems.
If it's fairly easy to do, so much the better--there's a better chance
that you won't have to fork somebody else's module to get it to work with
the level of B&D you want.
As for the core--in DBC, which is what started this thread in the first
place, the compiler and runtime do various correctness inferences based on
contracts. If you call some code that doesn't have a contract, you can
either blow up, or you can just assert that the code you're calling is
correct--at which point you can no longer guarantee your own contract.
It's not a stricture that can be lexically toggled off and on like a
pragma.
So if Perl 6 is going to support DBC, the core needs to support DBC too.
Nobody is forcing you to use DBC in order to use the core modules, though.
In fact, most DBC systems I'm aware of run in production with
contract-checking turned off; the checks are for testing and debugging.
So even DBC programs themselves have to be able to run at a lower level of
strictness.
In my opinion,Perl 6 should spell "no bondage":
#!/usr/bin/perl6
No, it should spell "no more, or less, bondage than you want".
Trey
