Re: My first USEFUL script!

Comments, in no particular order:

Where's use strict; and use warnings;? To me, putting these in perl code is like avoiding goto: it's good advice, and you should heed the advice until you know why the advice is given and you know why the advice may not apply to your current effort. (Let's just say I use "goto" far more often, especially in C, than I purposefully avoid using strict and warnings.) Granted, if your code works, it's probably fine, but you may find that the perl compiler (and interpreter) can give valuable advice, especially during development of a new script, just by turning these on.
I don't see anything wrong with explicitly using $_. Avoid it when you can, and you remember, but don't fret if you don't remember. Far more functions work when $_ is explicit than when you leave it out. ;-)
Use glob instead of the <> operator when expanding shell-like expressions as on your second line.
Personally, I avoid the map and grep EXPR versons, and always use the BLOCK versions. Admittedly, the EXPR version may be faster in some (many?) cases, but not only does the BLOCK version work in all cases, but I just find it clearer (no mental parsing for commas)
Finally, I'd have renamed the files to $_ . "5.8" instead of $_ . ".5.8" (e.g., "perl5.8" instead of "perl.5.8"). I think that's a bit more standard. Actually, I would not have renamed the old perl's at all - your system may have OS tools that are dependent on the system perl that probably have not been tested with perl 5.10. If they break with the new perl, Apple likely won't give you support. Instead, I'd call the new perl "perl5.10" and then I can have my own scripts with the line "#!/usr/local/bin/perl5.10" at the top to get the perl I want.

As for a rating, your scale is difficult to work with ;-) I'd have to say that if it worked, the rating automatically is decent. The only caveat really is that last point: system tools may expect the system perl to be the one that the system installed. Playing with that is always dangerous. But that isn't a comment on your perl code, it's more a comment on your unix-fu :-)

(Congrats :->)

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Re^2: My first USEFUL script! by nefigah (Monk) on Mar 05, 2008 at 05:16 UTC
Most appreciated :) strict/warnings: I actually had those in the original script; as they are a part of the template that I set up for creating a new script (along with the shebang line and some #created on comments), I didn't copy and paste them. But I agree :D $_: I'd been pointed to a general rule of thumb that explicitly saying $_ was to be avoided when possible (although that it is probably okay in grep/map). Glad to know there is some varying opinions on this though! glob: Roger, I'll keep that in mind--is it faster or something? blocks: Will keep that in mind as well Renaming: I'll go back and take out the dot--it does make more sense. As to OS tools breaking, I think I'll go ahead and see what happens. I can always put the originals back in place if stuff is being weird. Thank you for the word of caution :) The rating scale tends to be easy use for the extreme ends of the scale, which is what I was concerned with ;) Thank you for looking this over!!	[reply]
Re^3: My first USEFUL script! by ikegami (Patriarch) on Mar 05, 2008 at 06:51 UTC
Explicitly saying $_ is to be avoided when possible since you might as well as a meaningful variable name instead. However, that's obviously not the case when `map`/`grep` sets `$_` for you.	[reply] [d/l] [select]
Re^3: My first USEFUL script! by Tanktalus (Canon) on Mar 05, 2008 at 14:46 UTC
glob is more clear in general. For example, what does `<FILE>` do? Does it read a line (or all lines in list context) from the global filehandle 'FILE'? Or does it do a glob of 'FILE' in the current working directory? How about `<$fh>`? If $fh is "/usr/bin/perl*"? How about if $fh is an IO::File object? Or a reference to a global filehandle? If you want a glob, just use the glob function. That's what the `<>` does under the covers anyway. As for "stuff being weird" - you may not notice for 6 months... and by then you'll have forgotten that you replaced the system perl, and will beat your head against a wall trying to fix it ;-)	[reply] [d/l] [select]
Re^2: My first USEFUL script! by ikegami (Patriarch) on Mar 05, 2008 at 06:53 UTC
not only does the BLOCK version work in all cases There's a situation where it fails. I can't remember what it is, but it might be when you create a closure inside the `map` block. (The solution is to add an extra pair of braces, creating a new scope.) Of course, you'd have the same problem if you used the EXPR form (if it's even possible to write the buggy code in EXPR form), so this doesn't weaken your point.	[reply] [d/l]