meyerweb.com

Skip to: site navigation/presentation
Skip to: Thoughts From Eric

Archive: September 2004

A Few Spots of Fun

Just in case anyone cares, I’ve finally brought the Media Is Funny and CNN Is Funny pages out of dormancy.  They’re now caught up to this morning.  On a related note, I saw something this morning that didn’t really qualify for either page, but was worth sharing nonetheless.  The ad server at The Weather Channel coughed up a filler image today, and lucky me, I caught it.

A screenshot from weather.com showing a '300 x 600' placeholder in one of the advertisement spots.

So if you were ever curious about how much screen real estate that ad was chewing up… now you know.

Grammar Question

I was just recently asked if attribute selectors must use quotes around the value.  In other words, are both the following two selectors legal?

a[href="http://www.meyerweb.com"] {font-weight: bold;}
a[href=http://www.complexspiral.com] {font-style: italic;}

“No, they’re optional,” I said with assurance.  And then the doubts started to gnaw at me.  What if they actually weren’t, which might make sense given that you can require the exact match of a space-separated list of attribute values? By this, I mean that if you declare:

div[class="this is a test"] {color: orange;}

…then the selector will match any div element whose class attribute is exactly this is a test, in that order, and with nothing else in the attribute value.  Or so I’ve always been given to understand.  In that case, if you left off the quotes, couldn’t that somehow be confusing to the browser?  Maybe not, but it still bothered me.

So I went digging through CSS2.1, Appendix G and found the grammatical definition of an attribute selector.

attrib
  : '[' S* IDENT S* [ [ '=' | INCLUDES | DASHMATCH ] S*
    [ IDENT | STRING ] S* ]? ']'
  ;

You all understood that, right?  Uh-huh.  Me either.  (This is one of those hostile-to-outsiders posts I mentioned a while back.)

I never liked grammar in school, and I still don’t, but it is sometimes sadly necessary.  So here goes.  When you run down the definitions of the all-caps words (I think those are tokens) you find that IDENT is an identifier, which is sort of a catch-all bin for things like selectors, property names, values, and such.  Fine.  STRING, on the other hand, is a collection of symbols and other fun stuff, again including the non-ASCII range but not the ASCII range.  But then it includes the entirety of Unicode.  I’m not sure how much sense that makes, but whatever.

So the whole point of this is: if quotes around an IDENT are optional, wouldn’t it have made more sense to say this?

attrib
  : '[' S* IDENT S* [ [ '=' | INCLUDES | DASHMATCH ] S*
    [ STRING? IDENT STRING? ] S* ]? ']'
  ;

Or even:

attrib
  : '[' S* IDENT S* [ [ '=' | INCLUDES | DASHMATCH ] S*
    [ '"'? IDENT '"'? ] S* ]? ']'
  ;

It’s the [ IDENT | STRING ] from the original definition that has me befuddled.  It seems like it’s saying you can include an IDENT or a STRING but not both, and since IDENT doesn’t include quotes, that implies that you can either drop in an identifier, or a string with quotes.  Why is this a good idea?  Does it mean that any identifier has to be unquoted?  Does it mean that there’s no practical distinction between a STRING and an IDENT in this situation?  Does it mean that quotes prevent the inclusion of anything useful?  Somebody let me know.

Freezer Case

Since a few people asked for it, I’ve created a test file that reproduces the Internet Explorer freeze reported yesterday.  You can find it with the title “Internet Explorer Freezes — BEWARE!“.  If you follow that link with a non-IE browser, you should see a static copy of the “Ten Things To Do…” post, with two differences:

  1. I stripped off the theme stylesheet so the masthead graphic isn’t shown.
  2. I inserted a warning/explanatory comment near the top of the document.

Under the hood, the main difference is that the style sheets are all embedded in the document, so if you’re so inclined you can download that single page to your hard drive and fiddle with it to your heart’s content.  If anyone can narrow down this problem to a very minimal test case, I’d love to see it.  Refer back to “When Browsers Attack!” for notes on what I discovered.  There may well be more to the story, but if so, I didn’t find it.

I’ll reiterate the warning, in case it somehow wasn’t clear enough: iif you load this document in IE/Win, the odds are very, very, very high that it will freeze Internet Explorer, necessitating a force-quit of the application.  It may also crash Windows.  If you don’t want those sorts of things to happen to you, then don’t load the document.  Clear?  Good.

When Browsers Attack!

Remember my recently posted conversation with Molly?  Boy, am I ever feelin’ that today.  In spades.

Some of you have noticed earlier today that things were presentationally unstable.  Depending on when you dropped by, you would have seen raw document presentation with no author styles at all, or some chunks of the site’s usual styles but not others, or all of the usual styles with a few oddities thrown on top for good measure.  For a few hours, during which I had to attend to something else, the site was fine except that in IE/Win, the main content column was quite a bit wider than usual, and some bits of content were visually exceeding the edges of the design box.  All that was happening because I was turning styles on and off in an attempt to stop freezing Internet Explorer for Windows.

Freezing?  Oh, yes.  As in locking it up so that people had to use the Task Manager to force-quit the process.  There were probably a few reboots out there as well; there were at least a couple here in Casa de Meyer.  Ordinarily, I’d apologize.  Not this time.  If you want an apology, try finding the person or persons responsible for IE’s CSS handling, and demand an apology from them.  I’m not taking the rap for this.

To set the stage, let me back up a couple of days.  As I passed by Kat’s office, she called out, “Hey, how come my browser keeps getting screwed up?”

“Because it’s Explorer,” I said.  “Next question?”

“Ha ha.  Seriously, every time I try to view your ‘ten things to do in Cleveland‘ post, the computer crashes.  I think there’s something wrong with it.”

Grumbling, I wandered over to her computer.  Sure enough, the browser was completely frozen.  She’d already called up the Task Manager and was forcing the browser to quit.  She said it was the third time she’d had to do it.  As I watched, the screen went blank, then drew the desktop color and stopped.  The cursor appeared as an hourglass, and refused to change or even move.

Once the system had gone through a hard reboot, I fired up Netscape 7 and loaded up meyerweb.  I surfed around to various posts.  No problems at all.  I then launched IE and loaded up the home page.  No problem.  I went to the offending post.  Instant freeze.

After a few more invocations of the Fatal Freeze, I wandered out of her office again, muttering about Explorer and Windows and pondering the possibility that her computer had been infected with some kind of virus, malware, or other nastiness.  But then, the next day, I got some e-mail reporting similar problems.  Then Ian Firth managed to get a comment in about the problem on the post “Really Undoing html.css“, even though others were getting the Fatal Freeze on that very post.  And he mentioned that it was happening in both IE and FeedDemon—which meant it was something in IE’s rendering engine, since FeedDemon just wraps itself around the engine.  A similar report cropped up in the FeedDemon forums this morning, where it was mentioned that a similar problem had already been seen in the post “Standards Savings“.  (Not that anybody had actually bothered to tell me, but hey, whatever.)

So I fired up VirtualPC this morning and tested the problem for myself.  And sure enough, I was very quickly the latest resident of Lockup City.  So I started narrowing down the cause.  I’ll spare you all the nasty details (and foul language) of my bug hunt, and cut to the chase: the lockup was happening on entry pages where the post content included an element that used left padding.  Blockquotes and lists were the prime triggers.  There wasn’t an absolute 100% guarantee of trouble, but it was close.  I could avoid the freeze by commenting out a single declaration in my main style sheet:

#main {
  margin: 0 15em 0 0;
  /* padding: 3em 4em 3em 4em; */
  border-right: 1px solid #AAA;
  background: #FFF;
  min-height: 30em;
}

That’s why the content was running rampant earlier today.  I had to leave that line commented out for a few hours.  But I knew that couldn’t be the real cause, because it didn’t cause freezes on the home page, or even on monthly or daily archive pages.  The freeze only happened on an individual entry page where there was a padding-indented element inside the content column.  Thus, the source was most likely to lie in style sheet that’s applied only to post pages.

So I started digging through my entry style sheet until I narrowed the problem down to this line:

.prev-next {margin: 0; padding: 0.25em 1% 0; 
  float: left; width: 98%;}

If I commented it out, and uncommented the padding declaration from before, there were no problems.  So the culprit lay somewhere in the .prev-next rule.  Anyone want to guess at the cause?  Go ahead.

Oh, all right, I’ll tell you.  It was float: left;.  As soon as I removed that declaration, the IE6 freezing problem just melted away.  So if you’ve encountered freezes while trying to view entry pages in the past, you shouldn’t any more.  (If you do, please comment on this entry with the exact browser and OS you’re using.)

The original point of the float statement was to get the unordered list to wrap around the floated list items within it, since floated elements wrap around floated descendants (for more details, see my article “Containing Floats“).  Since that was apparently a recipe for disaster, I modified the rule to read:

.prev-next {margin: 0; padding: 0.25em 1% 0; 
  width: 98%; height: 1em;}

It isn’t exactly the same as what I was doing before, but the result is close enough for now.

What else might I have done?  Well, in all honesty, I thought seriously about leaving things status quo and letting IE users go hang.  I don’t cater to potential crash bugs in NN4, for example; why should I make an exception for another browser?  But as I always knew I would, I grumbled a bit and then made an accommodation for IE.  I may one day restore the float for more modern browsers and use some sort of hack to hide it from IE/Win, but for now I’ll leave things be.

What’s odd to me is that the styles involved in triggering this problem have been in place literally for months.  If this was a problem, it should have arisen before now.  Yet the first I heard of this freeze bug was two days ago, and then all of a sudden I was hearing about it from multiple sources.  If I’d been updating my CSS, that would be understandable, but I wasn’t.  So what happened?  Did the installed Explorer population just get spontaneously and collectively buggier over the weekend, or what?  Is there a subtle worm running around adding bugs to IE’s rendering engine?  I’m really at a loss here.

As to why that particular combination of styles would cause IE to freeze up, I’m completely at a loss.  Not a clue in the world.

While I was mucking around in the CSS anyway, I decided to see if I could fix the rendering error in IE/Win that made the sidebar hang out over the vertical separator.  I did, so far as I can tell.  The problem there was the “Exploration” box and the styles I’d applied to it.  Apparently, if you set a form element to width: 95%; margin-left 5%; and then set a text input within that form to width: 100%;, it all adds up to something like 120%, or something.  So I did a little bit of a hack to hide the input element’s width value from IE/Win.  The input box won’t be as wide for IE/Win users, but as far as I’m concerned that’s an acceptable loss.

I hope your morning was substantially less frustrating than mine.

When Blog Software Attacks!

Heard several times in 2002 and 2003: “Hey, Eric, how come you don’t use a blogging package for your site instead of that goofy XML/XSLT thing you cooked up?  It would make your archive URLs easier to remember, you could let people search, and comments would be possible.”

Oh, I don’t know… maybe because once I pour everything into a system, I’m subject to its quirks and whims, whereas if I roll my own system, it’s subject to my quirks and whims—and is thus tuned to my personal expectations, built to account for what I might choose to do even if I don’t realize it?

Despite this totally sensible attitude, I eventually did migrate to a system (WordPress).  That decision just bit me, thanks to its handling of markup in a post title.  Had the markup just been stripped out, that would be one thing—annoying, but totally understandable.  But to only sort-of strip it in the post slug and drop the markup raw into the title element, thus breaking any hope of validation?  Instead of, oh, I don’t know, maybe stripping the markup from both the title element and the post slug, but otherwise leaving it alone, so that the post title could remain marked up in the document itself?

<sigh type="frustrated" />

For the record, this is not evidence that WordPress sucks.  All packages suck in some way, and each one sucks in unique ways.  Eventually, you’re going to trip over something undesirable.  Today it was my turn to take that trip.

Now the post slug of emreallyem-undoing-htmlcss is enshrined forever, because you don’t change permalinks if you can possibly avoid it.  I can avoid it here by gritting my teeth, sucking it up, and wishing I had the programming moxie (not to mention spare time) to implement my own full-featured system.

Really Undoing html.css

There’s an aspect of document presentation most of us don’t consider: the browser defaults.  If you take an HTML or XHTML document—for the purposes of this exercise, assume it contains no presentational markup—and load it up in a Web browser with no CSS applied, there will still be some presentational effects.  A level-one heading, for example, is usually boldfaced and a good deal larger than other text, thus leading to the old stereotype of headings being “big and ugly”; the pre element typically honors whitespace and uses a monospace font; a paragraph is separated from other elements by a “blank line”; and so on.  From a CSS point of view, all this happens because the browser has built-in styles.

Tantek recently wrote about his creation of a file called undohtml.css, whose sole purpose is to strip away some of the default browser styles applied to common elements.  By resetting all headings to the same size, for example, he avoids the inconsistencies of heading sizes across browsers and brings everything to a common baseline.  If a different size is desired, the author has to do it manually.  (He should probably zero out the margins on headings as well, as those too tend to be inconsistent across browsers.)  He also zeroes out their margins, using a separate rule that I overlooked when I first posted.  Apologies to Tantek for my initial claim that he didn’t take that step.

Of course, Tantek isn’t really removing all the default styles, but (so far) just those that have given him the most trouble.  When it comes to Gecko-based browsers like Firefox and Mozilla, however, you can completely eliminate all built-in styles.  These browsers use a series of style sheets to control the presentation of documents, forms, MathML markup, and so on.  In OS X, you can find most of these style sheets by showing the package contents of the browser’s application file and navigating to Contents > MacOS > res.  On just about any other OS, it’s even easier; just search your hard drive for html.css and open the directory that contains that file.

If you look in html.css, you’ll find all of the styles that make what we think of as “unstyled” documents act the way they do.  Consider, for example:

area, base, basefont, head, meta, script, style, title,
noembed, noscript, param {
   display: none;
}

That rule is why the head element and all its contents don’t appear in your browser (as well as all those other “invisible” elements).  From a CSS standpoint, there’s nothing special about those elements as compared to others like div or ul.  The fact that they’re traditionally “invisible” is irrelevant—but with that one rule, the tradition is preserved.  You can always override the rule, of course; try style {display: block;} on a test document that contains an embedded style sheet and load it up in Firefox/Mozilla.  It isn’t magic.  It’s just a change from the usual way that documents are presented.  (See this test document for an example.)

There’s also:

/* nested lists have no top/bottom margins */
ul ul,   ul ol,   ul dir,   ul menu,   ul dl,
ol ul,   ol ol,   ol dir,   ol menu,   ol dl,
dir ul,  dir ol,  dir dir,  dir menu,  dir dl,
menu ul, menu ol, menu dir, menu menu, menu dl,
dl ul,   dl ol,   dl dir,   dl menu,   dl dl {
  margin-top: 0;
  margin-bottom: 0;
}

So in order to remove the top and bottom margins from nested lists, which is a traditional behavior of HTML browsers, that rule needs to be in the default style sheet.  Remove it, and nested lists would have top and bottom margins thanks to another rule in the style sheet:

ul, menu, dir {
  display: block;
  list-style-type: disc;
  margin: 1em 0;
  -moz-padding-start: 40px;
  -moz-counter-reset: -html-counter 0;
}

That rule not only sets the usual margins and such, but also includes some Mozilla-proprietary properties that help lists act in accordance with our expectations.  There are certain aspects of traditional presentation that aren’t (yet) fully describable using CSS, so the Mozilla folks have had to add properties.  In accordance with CSS2.1, section 4.1.2, these proprietary extensions are marked with a vendor prefix; here, it’s -moz-.  So any property or value you see starting with that string is a proprietary extension.  (For the record, I have no objection to extensions so long as they’re clearly marked as such; it’s the “silent” extensions that bug me.)

There is more to the presentation story than just html.css.  In the same directory, you can find quirk.css, which is applied instead of html.css when the browser is in “quirks” mode.  Another style sheet, viewsource.css, affects the presentation of any view source window.  All the nifty color-coding happens as a result of that style sheet, which is applied to automatically-generated markup that underlies the actual source you see.

So how do you completely strip out the default styles for an (X)HTML document?  Quit the browser application and rename the file html.css to something like html222.css.  Do the same for quirk.css.  Now re-launch the browser and find out just how much you’ve been taking for granted.  Feel free to browse around the Web and see what happens on various sites, but you’ll have to type blind, because the address bar won’t show any text.  You can still drag HTML documents on your hard drive into the window and see what happens.  If a document has any CSS applied to it, then the browser will use it.  It just won’t have any of the default styles available, so you’ll be applying your styles on top of nothing, instead of the usual foundation of expected presentation.

So what exactly is the point of all this?  As it turns out, I believe there are four:

  1. By studying html.css, beginning CSS users can compare the rules to the “unstyled” presentation of documents, and thus get a much better idea of how CSS works.
  2. By removing the default styles, you can come to a much greater realization of how much presentation is taken for granted, and how much there is to be dealt with when creating a new design.
  3. On a related note, note that the absolute bare minimum presentation of a document is to render all elements with inline boxes, and to show every scrap of content available.  Even something as basic as making a paragraph generate a block box is a style effect.
  4. It helps us to realize that what we often think of as the “special handling” of HTML is anything but: in Firefox/Mozilla, HTML documents are just a case of some markup that happens to have some pre-defined CSS applied to it.  Granted, the proprietary extensions needed to keep things in line with expectations are a case of special handling, and those tell us one of two things:
    • CSS still has a long way to go before it can be called a full-fledged layout tool, since it can’t fully recreate traditional HTML layout.
    • Old-school HTML layout was so totally wack, it’s no surprise that it’s hard to describe even with a tool like CSS at your disposal.
    I’ll leave it to the reader to decide which of those two they prefer.  Or, heck, choose both.  It isn’t as though they’re mutually exclusive.

Have fun fiddling with or completely removing the built-in styles!  Just remember: modifications like those described are made at your own risk, I’m not responsible if you do this and your hard drive vaporizes, no warranty is expressed or implied, not a flying toy, blah blah blah.

Scenes From An iChat Window

Excerpt from an IM session this afternoon:

Eric Meyer: Browsers– can’t live with ‘em, can’t kill their developers.

Molly Holzschlag: well one could …

Eric Meyer: Okay, but not legally.

Molly Holzschlag: justifiable homicide?

Eric Meyer: Juries are notoriously unsympathetic to technical explanations.

Molly Holzschlag: you have a point

Ten Things To Do In Cleveland Before You’re Dead

I quick-linked 10 Things to Do in Cleveland Before You Die, but the more I looked at the list, the less happy it made me.  So I’ve decided to compile my own list.  Note that this list doesn’t include restaurants.  As much as I love to eat, I just don’t think that a single meal is worthy of a “things to do before you’re dead” list, no matter how amazing the meal.  I might compile a separate “Ten Places to Eat In Cleveland” list, but that’s a subject for another day.

  1. Hear the Cleveland Orchestra.

    Not on CD, you goof—anyone can do that.  Hear them perform live and in person at least once in your life.  Odds are you’ll want to make it more than once, given that they’re one of the best orchestras in the world.  Bonus points for seeing them at Blossom Music Center, followed by a fireworks display.

  2. Tour the cultural institutions of University Circle.

    That includes the Cleveland Museum of Art; the Cleveland Museum of Natural History, which includes the Shafran Planetarium; the Western Reserve Historical Society, which includes the Crawford Auto-Aviation Museum; and the Cleveland Botanical Gardens, all within a quarter-mile radius.  Included in that grouping is Severance Hall, home of the Cleveland Orchestra.  This one’s kind of a cheat, since if I mentioned them all separately that would make this a “Top 15 Things To Do” list, which for some reason doesn’t sound as interesting.

  3. Spend a day at the Cleveland Metroparks.

    Known as the “Emerald Necklace”, the extensive park system (20,000 acres in 14 reservations) not only girds the city but also runs throughout the greater metropolitan area.  There are hiking trails, picnic areas, educational events, and a whole lot more, including the Cleveland Metroparks Zoo.

  4. Tour the Rock and Roll Hall of Fame.

    The real joy is in the smaller cases, where you can find original lyrics sheets to landmark songs complete with scratched-out ideas and arrows marking rearrangements, bills for hotel-room damage, and other tidbits.  The architecture of the building is fascinating as well.

  5. Visit the West Side Market.

    Besides the dozens of fruit and vegetable stalls in the outside promenade, the interior market space is filled with local butchers, bakers, and other amazing treats.  Come early on Saturday morning for the best selection.

  6. Spend Labor Day weekend downtown.

    That’s where and when you’ll find the Taste of Cleveland, a great way to sample various cuisines, while the aerial displays of the Cleveland National Air Show, based not half a mile away, soar overhead.  (Assuming the FAA relaxes its restrictions on such flights near sporting events, that is.)  If you stick around until nightfall, you’ll have a perfect excuse to go party in the Flats, too.

  7. Hit one of the amusement parks.

    Technically these aren’t in Cleveland itself, but they’re close enough to warrant inclusion.  About forty minutes southeast of downtown is Geauga Lake (formerly Six Flags Worlds of Adventure), a combination amusement park and water park.  Just over an hour west of downtown, you’ll find Cedar Point, one of the nation’s premiere amusements parks and the roller coaster capital of the world.

  8. Go sailing on Lake Erie.

    Whether you take out a two-man boat or take a dinner cruise on the Good Time III, it’s worth seeing the city from the water.  Even better, if you’re captain of your own boat, you can sail to one of the islands or head west along the shoreline to Cedar Point.

  9. See a game.

    With three major-league teams (the Indians, Browns, and Cavaliers) playing downtown, if you’re a sports fan, you’ll find a game to watch.  There are a number of other teams in town as well, including the Barons (hockey) and the Force (soccer).

  10. Drop by Lakeview Cemetery.

    Do it while you’re still alive, okay?  You’ll not only get great views of the city, but also see artistic, beautiful monuments to James A. Garfield, John D. Rockefeller, Eliot Ness, and others.  The Wade Chapel, situated on the shores of a pond, features an interior designed by Louis Comfort Tiffany and full of the famous glasswork bearing his name.  Who knows?  Maybe you’ll find a place to rest after you’re dead.

I have to be honest and admit that I haven’t even done everything on my own list.  However, I suspect that as our kids grow up, we’ll do all of those things more than once.

September 2004
SMTWTFS
August October
 1234
567891011
12131415161718
19202122232425
2627282930  

Archives

Feeds

Extras