Post by Mark Wieder
Post by Richard Gaskin
Remember that LiveCode is dynamically compiled - the only copy of a
script stored with a stack is the source copy, not any tokenized
version. So whenever you open a stack, as part of the unpacking its
scripts are dynamically compiled - and that's when the compilation error
OK - I see the difference. I've never considered turning explicitVars
on from the message box. The message box is a weird enough critter
that I wouldn't be surprised by unexpected consequences (OK - I
realize that's an oxymoron, but I can live with that).
My issue with LC's Message Box is that it's always in palette mode.
MC's is modeless, and the more I use Terminal the more I've come to
enjoy having the MB occasionally sized larger and always layerable with
my other windows.
So a while back when I had a free Saturday I started work on my own MB
replacement, and these days it's much easier to do a graceful
implementation because we now have the messageBoxRedirect global
property (thanks for that one, Kevin - I'm making good use of it).
At the time my main motivation was just to have an MB I could use as an
optional plugin in standalones but limited to specific commands in case
I chose to make it available for customers, but the more I got to using
it the more I found it simpler for day-to-day work in the IDE than LC's
mouse-driven MB UI (when you're typing, you're typing).
I've since added a bunch of shortcuts I use all the time, like listing
globals vars and props, and stack lists, and the message path, and other
stuff, and then I started down the road of implementing a few shell
calls like "ls" and "cd" - and of course now the challenge is to stop
doing that so I can just post it for others to use. I have an update
for devolution in the works that'll include it once I get a few client
things out of the way. It'll be MIT licensed so folks can tear it apart
and make their own if they want.
Post by Mark Wieder
But I've had explicitVars enabled from the preferences menu for years
and never had a problem. The IDE stacks are notoriously not
explicitVars-safe, so you'd expect there to be issues with them if
there were any problems with running in mixed mode.
The only "issues" I've had are when trying to compile someone else's
stack, plugin or no, that doesn't have declared variables.
That's the great thing about LC's current implementation in their IDE,
one of the areas in which I'd say it's a cut above MetaCard:
In MC, being close to the engine as it is, explicitVars is truly a
global property, and will require that everything you run has been
written to accommodate it.
In LC we have greater freedom in the sense that we can turn it on for
our own scripts while still using stuff from other people that doesn't
account for it.
Some history trivia for those who might care:
The explicitVars global property was added for SuperCard compatibility
back in the late '90s. SC was the first xTalk to have implemented
this, and I suppose that Raney, with his degree in CS focused on
compiler design, found it appealing, so unlike so many other SC- and
HC-specific compatibility tokens added as mere non-working stubs, this
one was added with full functionality.
But how did SC come to have explicitVars?
Back in those days the lead engineer for SuperCard was Gary Poppitz, a
man well versed in C and 68k Assembler. As far as I know no user had
ever requested it, he just felt it would be useful and put it in.
After he added that to SC I wondered if perhaps the benefit might be
compiler optimization, so I did some benchmarking. But on the
contrary, I found that running with it turned on actually made script
execution measurably slower than without (not by much though, maybe <5%,
and I've seen no difference in speed with LC's implementation, though
it's been years since I've benchmarked it).
So I asked Gary, "Why was explicitVars added?", and he said, "Because it
I write tons of code, and then I have to also write unit tests and
harnesses for it - and I need a new feature that requires even more
SC's implementation was like MC's (and ultimately LC's since of course
MC and LC are the same engine), in which it's truly global and requires
everything in the environment be compliant with it if it's to be used at
So while I had no personal interest in explicitVars myself, I used to
adhere to its requirements because I had no choice if I wanted to share
code with others who might have it turned on.
Now that RunRev has made this a more optional thing I'll admit I never
bother with it at all. I can understand why some do, but I really love
the freedom of being able to choose for myself whether I use it or not
for a given script.
Post by Mark Wieder Post by Richard Gaskin
PS: Sorry about being over-sensitive about the "trolling" thing. I've
known you for enough years that I should have been able to expect
nothing more than good humor from you. I'd just had a complicated
morning; thank you for replying so gracefully.
Not a problem on my end. Sorry about the unintentional slight. And
sorry about your morning - mine was weird as well. Sunspots? UFOs?
In my case it was UFOs: Uninteresting FUBAR Obstacles. :)
My mood has since elevated with news of some nice fixes in the LC engine
for Linux (including a particularly difficult one in which Mark
Waddingham worked around a GTK limitation to provide a workable
windowBoundingRect, at least for single-monitor setups - thanks Mark!),
and I very much enjoyed the notice on the Ubuntu.com home page
announcing their new 12.10 release with the tag line, "Avoid the pain of
Windows 8" (which they've since replaced with a much less interesting
tag line, but it made me chuckle while it was up <g>).
Like the Apple "1984", "Lemmings", and "I'm a Mac" ads, and the recent
ones from Samsung that turn the tables, sometimes a little controversy
isn't a bad thing; when done well it can even be fun (though I suppose
Win8 is an easy target given the press it's been getting, not to mention
Otellini's leaked memo).
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