Autocompleting ssh, rake, cap command parameters using PowerShell

Gaurav — Sun, 23 Nov 2008 19:42:54 +0000

I have mentioned in my previous posts that PowerShell has excellent and customizabme autocompletion support.
And some awesome plugins like powertab exist to take this functionality to another level.
Here is one easy way you can customize autocompletion easily by writing a couple of lines of code.

Open your PowerShell profile file (for help see here) and create a function with name "global:TabExpansion" in it.
This function basically overrides default autocompletion and sends your values to the prompt. For example for it to read your ssh files and display hosts in it the function would look something like this:

# customized tab expansionfunction global:TabExpansion {  param($line, $lastWord)    if ($line -match 'ssh'){    return cat C:\Users\Gaurav\.ssh\config | Select-String '^Host ' | % { if($_.Line -match "^Host ($lastword\S*)" ){ $matches[1] }}  }}

Here it is just parsing the config file and running it through a regular-expression and returning the results as an array. Here is what a typical ssh config file looks like:

Host blog  User username  HostName sitename.com  IdentityFile ~/.ssh/id_dsa  Host blog_2  User username  HostName sitename.com  IdentityFile ~/.ssh/id_dsa

Here is what the output looks like if I write “ssh ” and the press tab key twice:

Also this same function can easily be modded to autocomplete for ruby/rails commands like rake and cap.

Here is is my complete function:

# customized tab expansionfunction global:TabExpansion {  param($line, $lastWord)    if ($line -match 'ssh'){    return cat C:\Users\Gaurav\.ssh\config | Select-String '^Host ' | % { if($_.Line -match "^Host ($lastword\S*)" ){ $matches[1] }}  }  elseif ($line -match 'rake'){    rake -T | % { if($_ -match "^rake ($lastword\S*)" ){ $matches[1] }}  }   elseif ($line -match 'cap'){    cap -T | % { if($_ -match "^cap ($lastword\S*)" ){ $matches[1] }}  }}

Automating Powerpoint with ruby

Gaurav — Tue, 09 Oct 2007 10:50:27 +0000

We know that ruby is a language of few words. We can express a lot of things in a relatively easy manner.

I was trying to export few slides in my powerpoint presentation to an image format using ruby.I could not find any documentation for it anywhere except for a few basic things. But when I tried it by hit and trial I found out it to be surprisingly easy. It required just a few lines.

Here is what you have to do:

   1: require ‘win32ole’

   2: # open powerpoint

   3: ppt = WIN32OLE.new(‘Powerpoint.Application’)

   4: # make sure it is visible

   5: ppt.Visible = true

   6: # open the presentation to be exported

   7: pre = ppt.Presentations.Open(“d:\\imp_file.pptx”)

   8: # export the file

   9: pre.Slides(1).Export(“d:\\exp_file.png”,“png”)

  10: # close powerpoint, will close all the currently open files

  11: ppt.Quit()

You can always use RMagick to further process this image.

The Win32OLE extension library (actually spelled in lowercase, win32ole) provides an interface to Windows OLE automation. Your Ruby code can act as a client for any OLE automation server such as Microsoft Word, Outlook, and Internet Explorer and many other softwares.

So in the above code we are making a object is Powerpoint application, then opening a file and saving the first slide in the “png” format.

Gaurav » powerpoint

Autocompleting ssh, rake, cap command parameters using PowerShell

Automating Powerpoint with ruby