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Two Stanford students rethink the light switch - Nudge blog

2009 Feb 23, 11:04"...the two have designed what they are calling a SmartSwitch, which lets people know how much energy they are using, not through colors, but through tactile feedback."PermalinkCommentsecology ui interface hci energy light lightswitch

DIY Pepsi Challenge

2009 Jan 25, 5:39

Deutsches MuseumMicrosoft isn't completely shielded from our economies issues but I still have a job and still get free soda. While that's all still the case, I decided to test Sarah's claimed ability to differentiate between Pepsi, Coke, and their diet counterparts by taste alone. I poured the four sodas into marked cups and Sarah and I each took two runs through the cups with the following guesses.

Soda Identification Challenge Results
Drink Sarah Dave
Guess 1 Guess 2 Guess 1 Guess 2
Coke Coke Coke Pepsi Diet Pepsi
Diet Coke Diet Coke Diet Pepsi Diet Coke Diet Coke
Pepsi Pepsi Pepsi Coke Coke
Diet Pepsi Diet Pepsi Diet Coke Diet Pepsi Pepsi
Total (out of 8) 6 3

As you can see from the results, Sarah's claimed ability to identify Coke and Pepsi by taste is confirmed. The first run through she got completely correct and on the second run only mistook Diet Pepsi for Diet Coke. Her excuse for the error on the second run was a tainted palate from the first run. I on the other hand was mostly incorrect. Surprisingly though my incorrect answers were mostly consistent between run one and two. For instance I thought Pepsi was Coke in both runs.

PermalinkCommentscoke microsoft waste of soda pepsi waste of time soda

Google: If You Commit a Felony, Don't Google It or You'll Go to Jail

2009 Jan 20, 11:40"But, when police searched his computer, they found Google searches from a couple days after the accident like, "auto parts, auto dealers out-of-state; auto glass, Las Vegas; auto glass reporting requirements to law enforcement, auto theft," according to the prosecutor. The coup de grace? He searched for "hit-and-run," which he followed to a page about the hit-and-run he committed."PermalinkCommentsprivacy google internet crime

MAKE: Blog: Maker Profile - Bicycle Rodeo

2009 Jan 7, 6:15Ridiculously awesome creations of odd bicycles and creative things made from bicycle parts: "Introducing Cyclecide, an inventive band of Bay Area performance artists who make creations out of materials from the junkyard. These Makers create everything from amusement park rides to outrageous bicycle contraptions to found-object sculpture."PermalinkCommentsvideo make bicycle tv

Tab Expansion in PowerShell

2008 Nov 18, 6:38

PowerShell gives us a real CLI for Windows based around .Net stuff. I don't like the creation of a new shell language but I suppose it makes sense given that they want something C# like but not C# exactly since that's much to verbose and strict for a CLI. One of the functions you can override is the TabExpansion function which is used when you tab complete commands. I really like this and so I've added on to the standard implementation to support replacing a variable name with its value, tab completion of available commands, previous command history, and drive names (there not restricted to just one letter in PS).

Learning the new language was a bit of a chore but MSDN helped. A couple of things to note, a statement that has a return value that you don't do anything with is implicitly the return value for the current function. That's why there's no explicit return's in my TabExpansion function. Also, if you're TabExpansion function fails or returns nothing then the builtin TabExpansion function runs which does just filenames. This is why you can see that the standard TabExpansion function doesn't handle normal filenames: it does extra stuff (like method and property completion on variables that represent .Net objects) but if there's no fancy extra stuff to be done it lets the builtin one take a crack.

Here's my TabExpansion function. Probably has bugs, so watch out!


function EscapePath([string] $path, [string] $original)
{
    if ($path.Contains(' ') -and !$original.Contains(' '))
    {
        '"'   $path   '"';
    }
    else
    {
        $path;
    }
}

function PathRelativeTo($pathDest, $pathCurrent)
{
    if ($pathDest.PSParentPath.ToString().EndsWith($pathCurrent.Path))
    {
        '.\'   $pathDest.name;
    }
    else
    {
        $pathDest.FullName;
    }
}

#  This is the default function to use for tab expansion. It handles simple
# member expansion on variables, variable name expansion and parameter completion
# on commands. It doesn't understand strings so strings containing ; | ( or { may
# cause expansion to fail.

function TabExpansion($line, $lastWord)
{
    switch -regex ($lastWord)
    {
         # Handle property and method expansion...
         '(^.*)(\$(\w|\.) )\.(\w*)$' {
             $method = [Management.Automation.PSMemberTypes] `
                 'Method,CodeMethod,ScriptMethod,ParameterizedProperty'
             $base = $matches[1]
             $expression = $matches[2]
             Invoke-Expression ('$val='   $expression)
             $pat = $matches[4]   '*'
             Get-Member -inputobject $val $pat | sort membertype,name |
                 where { $_.name -notmatch '^[gs]et_'} |
                 foreach {
                     if ($_.MemberType -band $method)
                     {
                         # Return a method...
                         $base   $expression   '.'   $_.name   '('
                     }
                     else {
                         # Return a property...
                         $base   $expression   '.'   $_.name
                     }
                 }
             break;
          }

         # Handle variable name expansion...
         '(^.*\$)([\w\:]*)$' {
             $prefix = $matches[1]
             $varName = $matches[2]
             foreach ($v in Get-Childitem ('variable:'   $varName   '*'))
             {
                 if ($v.name -eq $varName)
                 {
                     $v.value
                 }
                 else
                 {
                    $prefix   $v.name
                 }
             }
             break;
         }

         # Do completion on parameters...
         '^-([\w0-9]*)' {
             $pat = $matches[1]   '*'

             # extract the command name from the string
             # first split the string into statements and pipeline elements
             # This doesn't handle strings however.
             $cmdlet = [regex]::Split($line, '[|;]')[-1]

             #  Extract the trailing unclosed block e.g. ls | foreach { cp
             if ($cmdlet -match '\{([^\{\}]*)$')
             {
                 $cmdlet = $matches[1]
             }

             # Extract the longest unclosed parenthetical expression...
             if ($cmdlet -match '\(([^()]*)$')
             {
                 $cmdlet = $matches[1]
             }

             # take the first space separated token of the remaining string
             # as the command to look up. Trim any leading or trailing spaces
             # so you don't get leading empty elements.
             $cmdlet = $cmdlet.Trim().Split()[0]

             # now get the info object for it...
             $cmdlet = @(Get-Command -type 'cmdlet,alias' $cmdlet)[0]

             # loop resolving aliases...
             while ($cmdlet.CommandType -eq 'alias') {
                 $cmdlet = @(Get-Command -type 'cmdlet,alias' $cmdlet.Definition)[0]
             }

             # expand the parameter sets and emit the matching elements
             foreach ($n in $cmdlet.ParameterSets | Select-Object -expand parameters)
             {
                 $n = $n.name
                 if ($n -like $pat) { '-'   $n }
             }
             break;
         }

         default {
             $varNameStar = $lastWord   '*';

             foreach ($n in @(Get-Childitem $varNameStar))
             {
                 $name = PathRelativeTo ($n) ($PWD);

                 if ($n.PSIsContainer)
                 {
                     EscapePath ($name   '\') ($lastWord);
                 }
                 else
                 {
                     EscapePath ($name) ($lastWord);
                 }
             }

             if (!$varNameStar.Contains('\'))
             {
                foreach ($n in @(Get-Command $varNameStar))
                {
                    if ($n.CommandType.ToString().Equals('Application'))
                    {
                       foreach ($ext in @((cat Env:PathExt).Split(';')))
                       {
                          if ($n.Path.ToString().ToLower().EndsWith(($ext).ToString().ToLower()))
                          {
                              EscapePath($n.Path) ($lastWord);
                          }
                       }
                    }
                    else
                    {
                        EscapePath($n.Name) ($lastWord);
                    }
                }

                foreach ($n in @(Get-psdrive $varNameStar))
                {
                    EscapePath($n.name   ":") ($lastWord);
                }
             }

             foreach ($n in @(Get-History))
             {
                 if ($n.CommandLine.StartsWith($line) -and $n.CommandLine -ne $line)
                 {
                     $lastWord   $n.CommandLine.Substring($line.Length);
                 }
             }

             # Add the original string to the end of the expansion list.
             $lastWord;

             break;
         }
    }
}

PermalinkCommentscli technical tabexpansion powershell

G1 Android Phone

2008 Nov 9, 11:29

T-Mobile G1 Wallpapers by romainguy
I finally replaced my old regular cell-phone which was literally being held together by a rubber band with a fancy new G1, my first Internet accessible phone.

I had to call the T-Mobile support line to get data added to my plan and the person helping me was disconcertingly friendly. She asked about my weekend plans and so I felt compelled to ask her the same. Her plans involved replacing her video card so she could get back to World of Warcraft and do I enjoy computer gaming? I couldn't tell if she was genuine or if she was signing me up for magazines.

I was with Sarah in her new car, trying out the phone's GPS functionality via Google Maps while she drove. I switched to Street View and happened to find my car. It was a weird feeling, kind of like those Google conspiracy videos.

The phone runs Google's open source OS and I really enjoy the application API. Its all in Java and URIs and mime-types are sort of basics. Rather than invoking the builtin item picker control directly you invoke an 'intent' specifying the URI of your list of items, a mime-type describing the type of items in the list, and an action 'PICK' and whatever is registered as the picker on the system pops up and lets the user pick from that list. The same goes if you want to 'EDIT' an image, or 'VIEW' an mp3.

I wanted to replace the Google search box gadget that appears on the home screen with my own search box widget that uses OpenSearch descriptors but apparently in the current API you can't make home screen gadgets without changing parts of the OS. My other desired application is something to replace this GPS photo tracker device by recording my location to a file and an additional program on my computer to apply those locations to photos.

PermalinkCommentstmobile personal api phone technical g1 android google

Investigation of a Few Application Protocols (Updated)

2008 Oct 25, 6:51

Windows allows for application protocols in which, through the registry, you specify a URL scheme and a command line to have that URL passed to your application. Its an easy way to hook a webbrowser up to your application. Anyone can read the doc above and then walk through the registry and pick out the application protocols but just from that info you can't tell what the application expects these URLs to look like. I did a bit of research on some of the application protocols I've seen which is listed below. Good places to look for information on URI schemes: Wikipedia URI scheme, and ESW Wiki UriSchemes.

Some Application Protocols and associated documentation.
Scheme Name Notes
search-ms Windows Search Protocol The search-ms application protocol is a convention for querying the Windows Search index. The protocol enables applications, like Microsoft Windows Explorer, to query the index with parameter-value arguments, including property arguments, previously saved searches, Advanced Query Syntax, Natural Query Syntax, and language code identifiers (LCIDs) for both the Indexer and the query itself. See the MSDN docs for search-ms for more info.
Example: search-ms:query=food
Explorer.AssocProtocol.search-ms
OneNote OneNote Protocol From the OneNote help: /hyperlink "pagetarget" - Starts OneNote and opens the page specified by the pagetarget parameter. To obtain the hyperlink for any page in a OneNote notebook, right-click its page tab and then click Copy Hyperlink to this Page.
Example: onenote:///\\GUMMO\Users\davris\Documents\OneNote%20Notebooks\OneNote%202007%20Guide\Getting%20Started%20with%20OneNote.one#section-id={692F45F5-A42A-415B-8C0D-39A10E88A30F}&end
callto Callto Protocol ESW Wiki Info on callto
Skype callto info
NetMeeting callto info
Example: callto://+12125551234
itpc iTunes Podcast Tells iTunes to subscribe to an indicated podcast. iTunes documentation.
C:\Program Files\iTunes\iTunes.exe /url "%1"
Example: itpc:http://www.npr.org/rss/podcast.php?id=35
iTunes.AssocProtocol.itpc
pcast
iTunes.AssocProtocol.pcast
Magnet Magnet URI Magnet URL scheme described by Wikipedia. Magnet URLs identify a resource by a hash of that resource so that when used in P2P scenarios no central authority is necessary to create URIs for a resource.
mailto Mail Protocol RFC 2368 - Mailto URL Scheme.
Mailto Syntax
Opens mail programs with new message with some parameters filled in, such as the to, from, subject, and body.
Example: mailto:?to=david.risney@gmail.com&subject=test&body=Test of mailto syntax
WindowsMail.Url.Mailto
MMS mms Protocol MSDN describes associated protocols.
Wikipedia describes MMS.
"C:\Program Files\Windows Media Player\wmplayer.exe" "%L"
Also appears to be related to MMS cellphone messages: MMS IETF Draft.
WMP11.AssocProtocol.MMS
secondlife [SecondLife] Opens SecondLife to the specified location, user, etc.
SecondLife Wiki description of the URL scheme.
"C:\Program Files\SecondLife\SecondLife.exe" -set SystemLanguage en-us -url "%1"
Example: secondlife://ahern/128/128/128
skype Skype Protocol Open Skype to call a user or phone number.
Skype's documentation
Wikipedia summary of skype URL scheme
"C:\Program Files\Skype\Phone\Skype.exe" "/uri:%l"
Example: skype:+14035551111?call
skype-plugin Skype Plugin Protocol Handler Something to do with adding plugins to skype? Maybe.
"C:\Program Files\Skype\Plugin Manager\skypePM.exe" "/uri:%1"
svn SVN Protocol Opens TortoiseSVN to browse the repository URL specified in the URL.
C:\Program Files\TortoiseSVN\bin\TortoiseProc.exe /command:repobrowser /path:"%1"
svn+ssh
tsvn
webcal Webcal Protocol Wikipedia describes webcal URL scheme.
Webcal URL scheme description.
A URL that starts with webcal:// points to an Internet location that contains a calendar in iCalendar format.
"C:\Program Files\Windows Calendar\wincal.exe" /webcal "%1"
Example: webcal://www.lightstalkers.org/LS.ics
WindowsCalendar.UrlWebcal.1
zune Zune Protocol Provides access to some Zune operations such as podcast subscription (via Zune Insider).
"c:\Program Files\Zune\Zune.exe" -link:"%1"
Example: zune://subscribe/?name=http://feeds.feedburner.com/wallstrip.
feed Outlook Add RSS Feed Identify a resource that is a feed such as Atom or RSS. Implemented by Outlook to add the indicated feed to Outlook.
Feed URI scheme pre-draft document
"C:\PROGRA~2\MICROS~1\Office12\OUTLOOK.EXE" /share "%1"
im IM Protocol RFC 3860 IM URI scheme description
Like mailto but for instant messaging clients.
Registered by Office Communicator but I was unable to get it to work as described in RFC 3860.
"C:\Program Files (x86)\Microsoft Office Communicator\Communicator.exe" "%1"
tel Tel Protocol RFC 5341 - tel URI scheme IANA assignment
RFC 3966 - tel URI scheme description
Call phone numbers via the tel URI scheme. Implemented by Office Communicator.
"C:\Program Files (x86)\Microsoft Office Communicator\Communicator.exe" "%1"
(Updated 2008-10-27: Added feed, im, and tel from Office Communicator)PermalinkCommentstechnical application protocol shell url windows

Party Movies Recommended by Netflix

2008 Sep 18, 10:31
Poster for 24 Hour Party PeoplePoster for Human TrafficPoster for The Boys and Girls Guide to Getting Down

Netflix has recommended three party movies over my time with Netflix and if you're OK with movies featuring sex, drugs, rock&roll (or techno) as almost the main character then I can recommend at least The Boys and Girls Guide to Getting Down.

24 Hour Party People is based on the true story of Tony Wilson, journalist, band manager, and club owner (not all at once) around the rise of punk and new wave in England. Like many true-story based movies it starts off strong and very interesting but gets very slow at the end like the writers got bored and just started copying the actual events. Unless you have some interest in the history of music in the 80s in Manchester I don't recommend this movie.

Human Traffic is fun and funny following a group of friends going out for a night of clubbing and partying. I had to get over seeing John Simm as not The Master from Doctor Who but rather as a partying youth. It felt like it was geared towards viewers who were on something like the totally odd techno musical interludes with the characters dancing for no apparent reason. Otherwise the movie was good.

The Boys and Girls Guide to Getting Down is done in the style of an old educational movie on the topic of clubbing and partying. It sounds like a premise that would get old but they do a good job. While demonstrating drinking and driving they have scientists push a mouse around in a toy convertible. Enough said. It was funny and I recommend it.

PermalinkCommentsparty movie netflix

rec.arts.sf.science qdFAQ

2008 Aug 26, 3:42Links to write ups on how much energy it would take to destroy the Earth or at least make it inhabitable in various fashions: "Destroying the Earth, It is often asked what it would take to shatter the Earth into little pieces. Erik Max Francis gives a rough answer. A less drastic measure would be to sterilise it by heating the outside. Brian Davis does the arithmetic, but I think he should have calculated what it would take to boil the oceans, which is a few thousand times more by my BotEC. Occasionally it is asked what would happen if you shot a fast-moving projectile at the Earth; I've written something up."PermalinkCommentsscifi science math

Network notary system thwarts man-in-the-middle attacks

2008 Aug 26, 10:03"A new system devised by Carnegie Mellon University researchers aims to thwart man-in-the-middle (MitM) attacks by providing a way to verify the authenticity of self-signed certificates. The system, which is called Perspectives, uses a distributed network of "notary" servers to evaluate the public key of a target destination so that its validity can be ascertained."PermalinkCommentssecurity ssl pki certificate man-in-the-middle

Tag Metadata in Feeds

2008 Aug 25, 10:13

As noted previously, my page consists of the aggregation of my various feeds and in working on that code recently it was again brought to my attention that everyone has different ways of representing tag metadata in feeds. I made up a list of how my various feed sources represent tags and list that data here so that it might help others in the future.

Tag markup from various sources
Source Feed Type Tag Markup Scheme One Tag Per Element Tag Scheme URI Human / Machine Names Example Markup
LiveJournal Atom atom:category yes no no , (source)
LiveJournal RSS 2.0 rss2:category yes no no technical
(soure)
WordPress RSS 2.0 rss2:category yes no no , (source)
Delicious RSS 1.0 dc:subject no no no photosynth photos 3d tool
(source)
Delicious RSS 2.0 rss2:category yes yes no domain="http://delicious.com/SequelGuy/">
hulu

(source)
Flickr Atom atom:category yes yes no term="seattle"
scheme="http://www.flickr.com/photos/tags/" />

(source)
Flickr RSS 2.0 media:category no yes no scheme="urn:flickr:tags">
seattle washington baseball mariners

(source)
YouTube RSS 2.0 media:category no no no label="Tags">
bunny rabbit yawn cadbury

(source)
LibraryThing RSS 2.0 No explicit tag metadata. no no no n/a, (source)
Tag markup scheme
Tag Markup Scheme Notes Example
Atom Category
atom:category
xmlns:atom="http://www.w3.org/2005/Atom"
category/@term
Required category name.
category/@scheme
Optional IRI id'ing the categorization scheme.
category/@label
Optional human readable category name.
term="catName"
scheme="tag:deletethis.net,2008:tagscheme"
label="category name in human readable format"/>
RSS 2.0 category
rss2:category
empty namespace
category/@domain
Optional string id'ing the categorization scheme.
category/text()
Required category name. The value of the element is a forward-slash-separated string that identifies a hierarchic location in the indicated taxonomy. Processors may establish conventions for the interpretation of categories.
domain="tag:deletethis.net,2008:tagscheme">
MSFT
Yahoo Media RSS Module category
media:category
xmlns:media="http://search.yahoo.com/mrss/"
category/text()
Required category name.
category/@domain
Optional string id'ing the categorization scheme.
scheme="http://dmoz.org"
label="Ace Ventura - Pet Detective">
Arts/Movies/Titles/A/Ace_Ventura_Series/Ace_Ventura_-_Pet_Detective
Dublin Core subject
dc:subject
xmlns:dc="http://purl.org/dc/elements/1.1/"
subject/text()
Required category name. Typically, the subject will be represented using keywords, key phrases, or classification codes. Recommended best practice is to use a controlled vocabulary.
humor

Update 2009-9-14: Added WordPress to the Tag Markup table and namespaces to the Tag Markup Scheme table.

PermalinkCommentsfeed media delicious technical atom youtube yahoo rss tag

"Small but Mighty Wandering Pearl" on Flickr - Photo Sharing!

2008 Jun 19, 11:57I saw '"Small but Mighty Wandering Pearl", an installation by Mandy Greer' at Bumbershoot and again at the Bellevue Arts Museum with some other of Mandy Greer's work. I must resist urge to roll around on the yarn everytime.PermalinkCommentsphoto art mandy-greer bumbershoot

NetFlix Media Center and Ong-Bak

2008 Jun 15, 7:57

Ong-Bak movie poster.I just installed vmcNetFlix which lets you watch your on demand NetFlix movies via your Vista Media Center or any Media Center Extenders like the Xbox 360. It works well but fails poorly with some cryptic error messages and long timeouts. Be sure to get NetFlix on demand movies working in your browser before installing this plugin. Once I did that everything worked very well.

To test it out I watched Ong-Bak: The Thai Warrior in which Ting must travel from his country village to Bangkok where he works with his cousin in the city to recover his village's stolen religious artifact. Its a mix of Perfect Strangers, Street Fighter and Pad-See Ew. Martial arts movies, like porn and video games, aren't required to have a strong plot but Ong-Bak has a fine plot line and enjoyable Thai martial arts. I saw the Tiger Knee in there several times. An enjoyable movie that reminded me of watching martial arts movies with my friends in high school.

PermalinkCommentsmedia-center thai netflix ong-bak vista

Golf Cart Parking

2008 May 28, 11:02

sequelguy posted a photo:

Golf Cart Parking

Kierland Commons shopping center next to the resort had fancy shops, hummers and golf carts.

PermalinkCommentsarizona sarah parking scottsdale golfcart kierlandcommons

Smithsonian Magazine | Arts & Culture | Showcasing Shams

2008 May 19, 11:46Museum of fraudulent art. "Instead of being destroyed, as they were in the past, the fraudulent pieces will live to see another day in the Museum of Fakes, established in 1991 as part of the University of Salerno's Center for the Study of Forgery."PermalinkCommentsart museum fraud via:boingboing

Leaking Information Through Delicious

2008 May 18, 6:45

While re-reading Cryptonomicon I thought about what kind of information I'm leaking by posting links on Delicious. At work I don't post any Intranet websites for fear of revealing anything but I wondered if not posting would reveal anything. For instance, if I'm particularly busy at work might I post less indicating something about the state of the things I work on? I got an archive of my Delicious posts via the Delicious API and then ran it through a tool I made to create a couple of tables which I've graphed on Many Eyes

I've graphed my posts per week and with red lines I've marked IE7 and IE8 releases as stated by Wikipedia. As you can see, there doesn't seem to be much of a pattern so I suppose my concerns we're unfounded. I use it for both work and non-work purposes and my use of Delicious isn't that consistent so I don't think it would be easy to find a pattern like I was thinking about. Perhaps if many people from my project used Delicious and that data could be compared together it might be easier.
For fun I looked at my posts per day of week which starts off strong on Mondays and decreases as the week goes on, and my posts per hour of day. It looks like I mostly post around lunch and on the extremes I've only posted very late at night twice at 4am: converting media for the Zune, and Penn's archive of articles. In the morning at 7am I've posted only once: document introducing SGML.PermalinkCommentsmanyeyes graph cryptonomicon delicious

URI Fragment Info Roundup

2008 Apr 21, 11:53

['Neverending story' by Alexandre Duret-Lutz. A framed photo of books with the droste effect applied. Licensed under creative commons.]Information about URI Fragments, the portion of URIs that follow the '#' at the end and that are used to navigate within a document, is scattered throughout various documents which I usually have to hunt down. Instead I'll link to them all here.

Definitions. Fragments are defined in the URI RFC which states that they're used to identify a secondary resource that is related to the primary resource identified by the URI as a subset of the primary, a view of the primary, or some other resource described by the primary. The interpretation of a fragment is based on the mime type of the primary resource. Tim Berners-Lee notes that determining fragment meaning from mime type is a problem because a single URI may contain a single fragment, however over HTTP a single URI can result in the same logical resource represented in different mime types. So there's one fragment but multiple mime types and so multiple interpretations of the one fragment. The URI RFC says that if an author has a single resource available in multiple mime types then the author must ensure that the various representations of a single resource must all resolve fragments to the same logical secondary resource. Depending on which mime types you're dealing with this is either not easy or not possible.

HTTP. In HTTP when URIs are used, the fragment is not included. The General Syntax section of the HTTP standard says it uses the definitions of 'URI-reference' (which includes the fragment), 'absoluteURI', and 'relativeURI' (which don't include the fragment) from the URI RFC. However, the 'URI-reference' term doesn't actually appear in the BNF for the protocol. Accordingly the headers like 'Request-URI', 'Content-Location', 'Location', and 'Referer' which include URIs are defined with 'absoluteURI' or 'relativeURI' and don't include the fragment. This is in keeping with the original fragment definition which says that the fragment is used as a view of the original resource and consequently only needed for resolution on the client. Additionally, the URI RFC explicitly notes that not including the fragment is a privacy feature such that page authors won't be able to stop clients from viewing whatever fragments the client chooses. This seems like an odd claim given that if the author wanted to selectively restrict access to portions of documents there are other options for them like breaking out the parts of a single resource to which the author wishes to restrict access into separate resources.

HTML. In HTML, the HTML mime type RFC defines HTML's fragment use which consists of fragments referring to elements with a corresponding 'id' attribute or one of a particular set of elements with a corresponding 'name' attribute. The HTML spec discusses fragment use additionally noting that the names and ids must be unique in the document and that they must consist of only US-ASCII characters. The ID and NAME attributes are further restricted in section 6 to only consist of alphanumerics, the hyphen, period, colon, and underscore. This is a subset of the characters allowed in the URI fragment so no encoding is discussed since technically its not needed. However, practically speaking, browsers like FireFox and Internet Explorer allow for names and ids containing characters outside of the defined set including characters that must be percent-encoded to appear in a URI fragment. The interpretation of percent-encoded characters in fragments for HTML documents is not consistent across browsers (or in some cases within the same browser) especially for the percent-encoded percent.

Text. Text/plain recently got a fragment definition that allows fragments to refer to particular lines or characters within a text document. The scheme no longer includes regular expressions, which disappointed me at first, but in retrospect is probably good idea for increasing the adoption of this fragment scheme and for avoiding the potential for ubiquitous DoS via regex. One of the authors also notes this on his blog. I look forward to the day when this scheme is widely implemented.

XML. XML has the XPointer framework to define its fragment structure as noted by the XML mime type definition. XPointer consists of a general scheme that contains subschemes that identify a subset of an XML document. Its too bad such a thing wasn't adopted for URI fragments in general to solve the problem of a single resource with multiple mime type representations. I wrote more about XPointer when I worked on hacking XPointer into IE.

SVG and MPEG. Through the Media Fragments Working Group I found a couple more fragment scheme definitions. SVG's fragment scheme is defined in the SVG documentation and looks similar to XML's. MPEG has one defined but I could only find it as an ISO document "Text of ISO/IEC FCD 21000-17 MPEG-12 FID" and not as an RFC which is a little disturbing.

AJAX. AJAX websites have used fragments as an escape hatch for two issues that I've seen. The first is getting a unique URL for versions of a page that are produced on the client by script. The fragment may be changed by script without forcing the page to reload. This goes outside the rules of the standards by using HTML fragments in a fashion not called out by the HTML spec. but it does seem to be inline with the spirit of the fragment in that it is a subview of the original resource and interpretted client side. The other hack-ier use of the fragment in AJAX is for cross domain communication. The basic idea is that different frames or windows may not communicate in normal fashions if they have different domains but they can view each other's URLs and accordingly can change their own fragments in order to send a message out to those who know where to look. IMO this is not inline with the spirit of the fragment but is rather a cool hack.

PermalinkCommentsxml text ajax technical url boring uri fragment rfc

Fragment Identification of MPEG Resources (Text of ISO/IEC FCD 21000-17 MPEG-21 FID)

2008 Apr 16, 7:09Standard describing URI fragments identifying parts of MPEG videos. Very similar syntax to XML fragments. Having trouble finding this document as anything other than a Word doc. Looks to exist only as an ISO standard.PermalinkCommentsstandard fragment uri video mpeg reference iso

14.3 Linking into SVG content: IRI fragments and SVG views

2008 Apr 16, 6:53SVG doc on how to make URI fragments that reference parts of an SVG document.PermalinkCommentsstandard svg w3c reference uri fragment

Warm Weekend

2008 Apr 14, 10:22

Cafe Pirouette ExteriorIt was warm and lovely out this past Saturday and Sarah I and went to a new place for lunch, then to Kelsey Creek Park, and then out for Jane's birthday. We ate at Cafe Pirouette which serves crepes and is done up with French decorations reminding me of my parent's house. We got in for just the end of lunch and saw the second to last customers, a gaggle of older ladies leaving. I felt a little out of place with my "Longhorn [heart] RSS" t-shirt on. The food was good and in larger portions that I expected.

Kelsey Creek FarmAfter that we went to Kelsey Creek Park and Farm. The park is hidden at the end of a quiet neighborhood, starts out with some tables and children's jungle gym equipment, then there's a farm which includes a petting zoo, followed by many little trails going off into the forrest. There weren't too many animals out and the ones we did see didn't seem to expect or want the sun and warm weather. We followed one of the trails for a bit and turned back before getting sun burned. You can see my weekend photos mapped out on Live Maps.

That night we went out with some friends for Jane's birthday. Eric was just back from the RSA conference and we met Jane and Eric and others at Palace Kitchen in Seattle located immediately adjascent to the monorail's route. The weather was still good so they left the large windows open through twilight and every so often you'd see the monorail pass by.

PermalinkCommentswashington bellevue weekend nontechnical
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