Sarah and I are back from Munich, Germany as of Thursday and I've just about recovered. The trip there via Air France we watched many movies and
it was much better than the trip back in which the entertainment system failed and I had a cold. When we arrived, Jon met us at the airport, helped us with the subway system, we played Guitar Hero,
ate at a Bavarian pub, and then later at an Australian bar.
The following day we met up with Jon and three of his friends, one of
whom was visiting from England and we all took a train to Neuschwanstein Castle. Apparently its the 'Disney' castle in that Disney's castle's are based upon it. The castle is filled with images and
statues of swans in homage to the Swan Knight. We ate in the town at a cafe with traditional Bavarian food before taking the train back and getting all you can eat fajitas for dinner.
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;
}
}
}
Electronic devices shouldn't fail, they should just sit wherever I place them and work forever. A while back my home web server started failing so I moved over to a real web hosting service. And this was the home web server I built from pieces Eric gave me after my previous one died during the big power failure the year before. The power socket on my old laptop has come undone from the motherboard so that it can no longer be powered. Just a week or two ago my Xbox 360 stopped displaying video. The CPU fan on my media center died. I also want to put my camera and GPS in this list, but the camera died due to accidentally turning on in my pocket and the GPS was stolen so those aren't the devices just arbitrarily failing.
I had an idea for a Facebook app the other day. I wondered who actually looked at my profile and thought I could create a Facebook app that would record this information and display it. When I talked to Vishu though he said that this wasn't something that Facebook would be too happy with. Indeed the Platform Policy explicitly disallows this in section 2.8. This explained why the app didn't already exist. Its probably for the best since everyone assumes they can anonymously view Facebook profiles and would be irritated if that weren't the case.
On the topic of assumed anonymity, check out this article on the aggregation and selling off of your cell phone data including your physical location.
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