This post is more for newcomers, than a response to stvn.

Yes, use assertions. Use boatloads of them.

 "assertions++" x 1000. Assertions rock. You will be surprised at how many bugs they detect.

And if you can (risk, speed, etc), leave them in and turned on in production code (with an appropriate handler, of course). (After all, these are assertions, and thus should NEVER happen, right?)

but...

Unless you're writing time-critical software in perl -- a game, a controller, etc (and one could ask, "errr, why in perl, then?" if that is indeed the case) -- then

  1. The program run time will very likely be dominated by IO, usually disk, db, network, web fetches, etc, and thus the speed difference between  assert (defined $foo, 'defined foo') and  defined $foo || die 'defined foo'; should be irrelevent in real code
  2. Machine time is cheap and Programmer time is expensive -- what is clearest? Which is easiest for others to read?
  3. Making assert a sub makes it Very Easy to change the assert behavior of the whole code base (logging, reponding to errors, correct shutdown in case of Really Bad Errors, etc), whereas the in-line || doesn't give you those options.
Last point aside, IMHO, it really doesn't matter if a shop opts for  assert vs.  ||, as long as the gang uses the idiom consistently. I personally like  assert, because to me is is more clear, and more flexible, but I also prefer Pepsi to Coke -- many of these things are just individual preference.

And as for ensuring an entire code base meets explicit coding standards -- well, this is great use of perl testing. just File::Find::Rule or whatever and  Test::More the whole source tree and apply regexps to every module and program, such that code that doesn't meet standard fails the test and 'breaks the build'.

From what I've read here, stvn is a far more advanced coder than I. This is not a criticism of his post or his method, just a caution to the less-experienced: Premature optimization is the root of all evil .

Don't worry about speed difference until you know your program is running too slowly, then rationally determine what is creating the bottleneck. And I'd bet you lunch that, unless you have contrived code, the bottleneck won't be your assertions. No way. 

 
"assertions++" x 1000;
"coding_standards++" x 1000;
"'worrying about speed of assert vs. ||' -- ";

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In reply to Re: Being more Assert-ive with Perl by water
in thread Being more Assert-ive with Perl by stvn

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