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;
}
}
}
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.
Internet Explorer 8 Beta 2 is now available! Some of the new features from this release that I really enjoy are Tab Grouping, the new address-bar, and InPrivate Subscriptions.
Tab Grouping groups tabs that are opened from the same page. For example, on a Google search results page if you open the first two links the two new tabs will be grouped with the Google search results page. If you close one of the tabs in that group focus goes to another tab in that group. Its small, but I really enjoy this feature and without knowing exactly what I wanted while using IE7 and FF2 I knew I wanted something like this. Plus the colors for the tab groups are pretty!
The new address bar and search box makes life much easier by searching through my browsing history for whatever I'm typing in. Other things are searched besides history but since I ignore favorites and use Delicious I mostly care about history. At any rate its one of the things that makes it impossible for me to go machines running IE7.
InPrivate Subscriptions allows you to subscribe to a feed of URLs from which IE should not download content. This is intended for avoiding sites that track you across websites and could sell or share your personal information, but this feature could be used for anything where the goal is to avoid a set of URLs. For example, phishing, malware sites, ad blocking, etc. etc. I think there's some interesting uses for this feature that we have yet to see.
Anyway, we're another release closer to the final IE8 and I can relax a little more.
Some rights reserved