function page 3 - Dave's Blog

Search
My timeline on Mastodon

HP All-in-Ones-The Scan Button on the All-in-One Does Not Function When the Printer is Connected to Windows Vista

2009 Jun 20, 9:45"When the scan button is pressed on the product, nothing happens. The scan button does not work correctly." The workarounds are all basically, "don't use that button then." They say their Vista driver doesn't support sending the appropriate event. Lame.PermalinkCommentsvista hp scanner driver lame technical

Flickr Visual Search in IE8

2009 Apr 10, 9:48

A while ago I promised to say how an xsltproc Meddler script would be useful and the general answer is its useful for hooking up a client application that wants data from the web in a particular XML format and the data is available on the web but in another XML format. The specific case for this post is a Flickr Search service that includes IE8 Visual Search Suggestions. IE8 wants the Visual Search Suggestions XML format and Flickr gives out search data in their Flickr web API XML format.

So I wrote an XSLT to convert from Flickr Search XML to Visual Suggestions XML and used my xsltproc Meddler script to actually apply this xslt.

After getting this all working I've placed the result in two places: (1) I've updated the xsltproc Meddler script to include this XSLT and an XML file to install it as a search provider - although you'll need to edit the XML to include your own Flickr API key. (2) I've created a service for this so you can just install the Flickr search provider if you're interested in having the functionality and don't care about the implementation. Additionally, to the search provider I've added accelerator preview support to show the Flickr slideshow which I think looks snazzy.

Doing a quick search for this it looks like there's at least one other such implementation, but mine has the distinction of being done through XSLT which I provide, updated XML namespaces to work with the released version of IE8, and I made it so you know its good.

PermalinkCommentsmeddler xml ie8 xslt flickr technical boring search suggestions

[whatwg] [WhatWG] Some additional API is needed for sites to see whether registerProtocolHandler() call was successful

2009 Apr 7, 12:14This makes plenty of sense, that a site should be able to check if a protocol handler exists for some URI scheme, but it'd be nice if this were some sort of declaritive fallback plan rather than having to do it all with script. "The HTML5 standard function registerProtocolHandler() should probably remain void as in standard, but WhatWG could invent yet another boolean protocolRegistered("area"), with the only argument (protocol name as string), to check whether a protocol is registered."PermalinkCommentshtml5 registerProtocolHandler html script url uri scheme protocol

The Old New Thing : The history of calling conventions, part 5: amd64

2009 Apr 1, 6:19"The first four parameters to a function are passed in rcx, rdx, r8 and r9. Any further parameters are pushed on the stack. Furthermore, space for the register parameters is reserved on the stack, in case the called function wants to spill them; this is important if the function is variadic."PermalinkCommentsamd64 calling-convention debug x64 msdn raymond-chen assembly

Internet Explorer 8 Released

2009 Mar 20, 6:18

Our Fearless Leader reveals IE8 at MIX09. Photo by DBegley.IE8, the software I've been working on for some time now, has finally been released at MIX09.

As I mentioned previously, I worked on accelerators (previously named Activities) in IE8. Looking at the kinds of things I blog about on the IE Blog, you might also correctly guess that I work on the networking stack. Ask me about what else I worked on during IE8 development. The past few months were very busy for me and I'm happy this is finally out.PermalinkCommentstechnical internet explorer ie8

Proxy Client Autoconfig File Format

2009 Feb 5, 8:47Copy of the Netscape Navigator document (the original's long gone) describing the Proxy Auto-Config (PAC) file format and mime-type. Its a javascript file with at least one well known function that, given a host, returns a string describing which methods are appropriate for a web browser to connect to that host.PermalinkCommentsjavascript pac proxy http reference netscape navigator

Windows PowerShell Core

2008 Nov 19, 3:34PowerShell function syntax and helpPermalinkCommentspowershell reference microsoft msdn function shell

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

Word Wrapping IE's Plain Text

2008 Oct 28, 11:23

If you view a plain text document in Internet Explorer 8, for instance the plain text version of Cory Doctorow's book Little Brother and press F12 to bring up the developer toolbar, you can see that IE simply takes the plain text, sticks it inside a

 tag, and renders it.  This means that word wrapping isn't supplied and the only line breaks that appear are those in the document.  However, since the text document is converted to HTML it means I can implement word wrap myself using a bookmarklet:
javascript:function ww() { var preTag = document.getElementsByTagName('pre')[0]; preTag.style.fontFamily="arial"; preTag.style.wordWrap='break-word'; }; ww();
After adding a favorite and setting the favorite's URL to the previous, I can view plain text documents, and select my Word Wrap favorite to apply word wrap and non-fixed width font.
PermalinkCommentsbrowser technical ie wordwrap

Mozilla Labs launches geolocation extension

2008 Oct 13, 2:21Neat geolocation API for web apps: "Mozilla Labs has announced the availability of Geode, an experimental Firefox extension that implements the W3C Geolocation Specification. Geode provides an early preview of the same location-aware functionality that will be included in both Fennec and Firefox 3.1."PermalinkCommentsgeolocation geo w3c mozilla javascript web

Disemvowelment and Reemvowelment Tools

2008 Oct 3, 5:29I thought the disemvowelment of trolls was a pretty funny punishment -- much better than simply removing the comment: "Disemvowelment is - obviously enough - the act of removing the vowels from a passage of text, as well as a pun on the word 'disembowelling'. A number of blogs and websites do this to offensive text which has been placed in their 'comments' section. ... This site exists because I couldn't resists the challenge of trying to re-emvowel disemvowelled text. This is a challenging task, as the disemvowelled word 'dg' may well have been 'dog', but also 'dig', 'dug', 'doge', diego' and so on. I have a first cut of this functionality at the re-emvowel link at the side of the page. A more advanced version is in progress."PermalinkCommentstool disemvowelment web comment forum troll language

The Quantified Self

2008 Sep 16, 4:56All about self-trackers who track and graph all sorts of personal data. I suppose mycrocosm is like the self-tracker's twitter. "A quick overview of the emerging culture of self-tracking ran in the Washington Post the other day. Called "Bytes of Life: For Every Move, Mood and Bodily Function, There's a Web Site to Help You Keep Track." The subtitle is a gross exaggeration, although in time it will be true."PermalinkCommentsprivacy data social personal kevin-kelly

Why Verbs? - Not The User's Fault

2008 Aug 28, 11:15I can't say why this is funny: "First, the really big picture of what Ubiquity is supposed to be all about: It's a step towards a Web where verbs (i.e. functionality, i.e. commands, i.e. services) are first-class citizens. And that's why I'm thinking it should be renamed from Ubiquity to something like "Mozilla Verbs", maybe."PermalinkCommentsmozilla firefox ubiquity ui via:ethan_t_hein

Deriving a Non-Recursive Fibonacci Function Using Linear Algebra

2008 Aug 20, 10:51

In my Intro to Algorithms course in college the Fibonacci sequence was used as the example algorithm to which various types of algorithm creation methods were applied. As the course went on we made better and better performing algorithms to find the nth Fibonacci number. In another course we were told about a matrix that when multiplied successively produced Fibonacci numbers. In my linear algebra courses I realized I could diagonalize the matrix to find a non-recursive Fibonacci function. To my surprise this worked and I found a function.
The Nth Fibonacci value is (1 + sqrt(5))^N - (1 - sqrt(5))^N all over sqrt(5) * 2^N
Looking online I found that of course this same function was already well known. Mostly I was irritated that after all the algorithms we created for faster and faster Fibonacci functions we were never told about a constant time function like this.

I recently found my paper depicting this and thought it would be a good thing to use to try out MathML, a markup language for displaying math. I went to the MathML implementations page and installed a plugin for IE to display MathML and then began writing up my paper in MathML. I wrote the MathML by hand and must say that's not how its intended to be created. The language is very verbose and it took me a long time to get the page of equations transcribed.

MathML has presentation elements and content elements that can be used separately or together. I stuck to content elements and while it looked great in IE with my extension when I tried it in FireFox which has builtin MathML support it didn't render. As it turns out FireFox doesn't support MathML content elements. I had already finished creating this page by hand and wasn't about to switch to content elements. Also, in order to get IE to render a MathML document, the document needs directives at the top for specific IE extensions which is a pain. Thankfully, the W3C has a MathML cross platform stylesheet. You just include this XSL at the top of your XHTML page and it turns content elements into appropriate presentation elements, and inserts all the known IE extension goo required for you. So now my page can look lovely and all the ickiness to get it to render is contained in the W3C's XSL.

PermalinkCommentstechnical mathml fibonacci math

Divination - A New Perspective - JSTOR: American Anthropologist, New Series, Vol. 59, No. 1 (Feb., 1957 ), pp. 69-74

2008 Jul 9, 5:37Moore proposes magical divination fills function of generating random outcomes. E.g. shaman reading cracks in caribou bones determines where to hunt avoiding over hunting particular areas or the game picking up hunters patterns. Wish this wasn't pay site.PermalinkCommentsrandom game-theory anthropology divination magic

Create a Windows Clipboard Monitor in C# using SetClipboardViewer API - Rad Software

2008 Apr 21, 2:58"This example shows you how to use the Win32 API function SetClipboardViewer to create a Clipboard Viewer application" and the example is in C# and VB.Net.PermalinkComments.net csharp clipboard programming windows setclipboardviewer dllimport

Encoding methods in C#

2008 Apr 12, 10:38

For Encode-O-Matic, my encoding tool written in C#, I had to figure out the appropriate DllImport declarations to use IDN Win32 functions which was a pain. To spare others that pain here's the two files CharacterSetEncoding.cs and NationalLanguageSupportUtilities.cs that declare the DllImports for IdnToUnicode, IdnToAscii, NormalizeString, MultiByteToWideChar, and WideCharToMultiByte.

PermalinkCommentsencodeomatic boring csharp widechartomultibyte idn tool dllimport

Zeno's Progress Bar - Stolen Thoughts

2008 Apr 7, 10:09

Text-less progress bar dialog. Licensed under Creative Commons by Ian HamptonMore of my thoughts have been stolen: In my previous job the customer wanted a progress bar displayed while information was copied off of proprietary hardware, during which the software didn't get any indication of progress until the copy was finished. I joked (mostly) that we could display a progress bar that continuously slows down and never quite reaches the end until we know we're done getting info from the hardware. The amount of progress would be a function of time where as time approaches infinity, progress approaches a value of at most 100 percent.

This is similar to Zeno's Paradox which says you can't cross a room because to do so first you must cross half the room, then you must cross half the remaining distance, then half the remaining again, and so on which means you must take an infinite number of steps. There's also an old joke inspired by Zeno's Paradox. The joke is the prototypical engineering vs sciences joke and is moderately humorous, but I think the fact that Wolfram has an interactive applet demonstrating the joke is funnier than the joke itself.

I recently found Lou Franco's blog post "Using Zeno's Paradox For Progress Bars" which covers the same concept as Zeno's Progress Bar but with real code. Apparently Lou wasn't making a joke and actually used this progress bar in an application. A progress bar that doesn't accurately represent progress seems dishonest. In cases like the Vista Defrag where the software can't make a reasonable guess about how long a process will take the software shouldn't display a progress bar.

Similarly a paper by Chris Harrison "Rethinking the Progress Bar" suggests that if a progress bar speeds up towards the end the user will perceive the operation as taking less time. The paper is interesting, but as in the previous case, I'd rather have progress accurately represented even if it means the user doesn't perceive the operation as being as fast.

Update: I should be clearer about Lou's post. He was actually making a practical and implementable suggestion as to how to handle the case of displaying progress when you have some idea of how long it will take but no indications of progress, whereas my suggestion is impractical and more of a joke concerning displaying progress with no indication of progress nor a general idea of how long it will take.

PermalinkCommentszenos paradox technical stolen-thoughts boring progress zeno software math

Feed Folder Deprecated; Use Internet Explorer 8

2008 Mar 7, 7:20

Internet Explorer 8 has made my plugin Feed Folder obselete in functionality and implementation -- which is good!

IE8's Feed Folder feature screen shot.IE7 Feed Folder plugin screen shot.

I made Feed Folder for IE7 because I wanted the Live Bookmarking feature from FireFox. The Feed Folder plugin for IE7 would allow you to display your feeds as virtual folders in your Links Bar. When your feed is updated the virtual folder is updated as well with the new feed items. I use del.icio.us to store all my links so I could add virtual folders of my daily links, my friends blogs links, quick reference links, etc. etc.

My plugin relied on shell folders to implement the virtual folders I described above, but IE8 doesn't support shell folders in the Favorites Bar. But I'm OK with Feed Folder not working in IE8 since there's a much better implementation already there. IE8 does better than my plugin on a number of points: First, there isn't the horrible perf. issue that my plugin had on Vista. Second, when a feed is updated the virtual folder flashes to note the change in status. Third, unread items are bolded and the bolding bubbles up from feeds contained in subfolders. And lastly, the middle click button is supported to open items in a new tab.

Accordingly, I don't plan to work on Feed Folder anymore unless someone comes up with a good reason. Instead I mark Feed Folder deprecated and suggest you use Internet Explorer 8 instead.

To use this feature in IE8 simply drag a feed from your feed list in your Favorites Center onto your Favorites Bar. Or, when viewing a feed, click on the 'Add to Favorites' Star Plus icon thing in the upper left, and select 'Monitor on Favorites Bar'. A .url Internet Shortcut file is produced as usual, but if you open up the .url file you'll see there's some additional info about the feed.

PermalinkCommentsie8 feed feedfolder plugin technical browser ie rss
Older EntriesNewer Entries Creative Commons License Some rights reserved.