Unquoting Your Hash Keys · 497 days ago by Dylan Doxey
I once thought it was pretty neat to format my hash keys like this.
1 use strict;
2 use warnings;
3
4 my $day = $date_rh->{ 'day' };
5 my $month = $date_rh->{ 'month' };
6 my $year = $date_rh->{ 'year' };
7
I have now flipped from that flop.
Here's how I like to see my keys formatted now.
1 use strict;
2 use warnings;
3
4 my $day = $date_rh->{day};
5 my $month = $date_rh->{month};
6 my $year = $date_rh->{year};
7
Now whenever I open up a program and start making tweaks one of the first things to go is the old line bloating style of hash keys.
However, this is an excersize in tedium when one is not adept with vim pattern matching.
So here's a tip.
:%s/{[ ]*'\([A-Za-z0-9_]\+\)'[ ]*}/{\1}/g
The key with this pattern is knowing what to escape with the backslash. Here you can see that the pattern meta-characters are backslashed.
Enjoy.
Roku BrightScript Syntax Highlighting in Vim · 609 days ago by Dylan Doxey
I don't know how everyone else is editing their BrightScript code, but I want to use vim.
1 ' ********************************************************************
2 ' ** Sample PlayVideo App
3 ' ** Copyright (c) 2009 Roku Inc. All Rights Reserved.
4 ' ********************************************************************
5
6 Sub Main()
7 'initialize theme attributes like titles, logos and overhang color
8 initTheme()
9
10 'display a fake screen while the real one initializes. this screen
11 'has to live for the duration of the whole app to prevent flashing
12 'back to the roku home screen.
13 screenFacade = CreateObject("roPosterScreen")
14 screenFacade.show()
15
16 itemMpeg4 = { ContentType:"episode"
17 SDPosterUrl:"file://pkg:/images/DanGilbert.jpg"
18 HDPosterUrl:"file://pkg:/images/DanGilbert.jpg"
19 IsHD:False
20 HDBranded:False
21 ShortDescriptionLine1:"Dan Gilbert asks, Why are we happy?"
22 ShortDescriptionLine2:""
23 Description:"Harvard psychologist Dan Gilbert says our beliefs about what will make us happy are often wrong -- a premise he supports with intriguing research, and explains in his accessible and unexpectedly funny book, Stumbling on Happiness."
24 Rating:"NR"
25 StarRating:"80"
...
Unfortunately there's no syntax highlighting defined for Roku BrightScript. So I wrote my own.
The procedure goes roughly in two steps.
- create: /usr/share/vim/vim72/syntax/brs.vim
- add brs to: /usr/share/vim/vim72/filetype.vim
I've never created a vim syntax file before, so I decided to use the vb.vim syntax file as starter code. That served as a decent foundation to hack around and learn how the syntax file syntax works. While I was hacking the syntax file I kept a .brs program open in another instance of vim so that I could periodically reload the buffer (:e!) to see the effect of my changes. After all the hacking and experimentation, my brs.vim didn't very much resemble the vb.vim that I'd started with.
What I learned about the way the syntax file works:
- There are a number of predefined categories of syntax which map to distinct highlight colors.
- The syntax file defines keyword and pattern lists which are then related to any of the predefined syntax categories.
- The patterns can be regexes such as . matches any character. (So use "\." if you want the . character to match.)
- The syntax file has a lot of sophisticated capability which I didn't explore.
Adding the correct entry in filetype.vim was as simple as adding:
au BufNewFile,BufRead *.brs setf brs
Here's my brs.vim if you'd like to take a look for yourself (last updated July 2011).
Doing It The jQuery Way · 623 days ago by Dylan Doxey
Here's (a slimmed version of) one of the more intersting bits of JavaScript code I've written recently.
var refresh_ui = function() {
$('#keyword_select').load('/keywords?action=list');
}
var save = function() {
var item_id = $('#item_select').val();
var keywords = $('#keyword_select').val();
return $.post( '/settings/keywords',
{
action : 'save',
item_id : item_id,
keywords : keywords,
},
refresh_ui
);
};
$('#save_button').click(save);
This snippet illustrates several ways of doing things using jQuery that break from the old norm:
- defining anonymous functions vs. named functions
- describing data structures with inline JSON vs. building associative arrays
- getting items with CSS selectors vs. getElementById (or something even more messy)
- assigning event handlers by passing the function object directly
- unspeakably more consice .load and .post functions.
I used to pride myself on writing fancy AJAX interfaces for each individual application. But golly, nothing I ever did approached the simplicity and elegance of just doing $('#item').load('/url/path');.
Don't reinvent the wheel. Stand on the shoulders of giants and move on to developing something else.
Dynamic Accessor Methods · 625 days ago by Dylan Doxey
So here I am writing this module which pulls a database record that is keyed by a topic keyword. And each accessor method was just a copy of the one preceding it, over and over. To make matters worse, each time there's a new topic added to the database am I to go an add yet another accessor method? Not.
Introducing the dynamic accessor method.
...
for my $topic (@topics) {
my $method_name = sprintf '%s::get_%s', __PACKAGE__, $topic;
my $method_rc = sub {
my $self = shift;
my $page_rh = $self->{db}->select_rh( {
from => 'content',
where_rh => {
topic => $topic,
},
} );
$page_rh->{text} //= $MT_STR;
return $page_rh->{text};
};
{
no strict 'refs';
*{$method_name} = $method_rc;
}
}
...
Changing Case in Vim · 631 days ago by Dylan Doxey
Every once in a while I'm preparing some text for something or other and I think, "I sure would like to change all of this text to lower case."
... 50 504 gateway_timeout 51 505 http_version_not_supported 52 506 variant_also_negotiates 53 507 insufficient_storage 54 509 bandwidth_limit_exceeded 55 510 not_extended :'<,'>!tr A-Z a-z
This vim command is composed of three parts:
- '<,'> -- this is the region of highlighted text.
- ! -- what follows is a shell command
- tr A-Z a-z -- translate class [A-Z] to [a-z] (same as Perl tr/[A-Z]/[a-z]/).
I'm sure to be back for this snippet soon.
HTML Formatting Your Perl · 638 days ago by Dylan Doxey
Ever wonder how to make your Perl code presentable on a website? Use perltidy.
perltidy -html rand_sort.pl
Then cut & paste the resulting HTML into your blog and delight your readers.
#!/usr/bin/perl use strict; use warnings; my @numbers = sort { -1 + int rand 3 } 1 .. 1000; for my $x (@numbers) { print "$x\n"; }
However, in my opinion the best option for a blog snippet is vim. While you've got your Perl (or whatever) file open in vim use the :TOhtml command. That will open another buffer with HTML in it. The resulting HTML page is:
1 #!/usr/bin/perl
2
3 use strict;
3 use warnings;
4
5 my @numbers = sort { -1 + int rand 3 } 1 .. 1000;
6
7 for my $x (@numbers) {
8
9 print "$x\n";
10 }
11
For more information about using perltidy see http://perltidy.sourceforge.net/perltidy.html#html_options. For the record, my example of perltidy HTML output is pretty lame. As linked from the perltidy home page (http://perltidy.sourceforge.net/) check out this example of perltidy HTML output: http://perltidy.sourceforge.net/Conf.pm.html.
For more details about using :TOhtml user command in vim see http://vimdoc.sourceforge.net/htmldoc/syntax.html#:TOhtml
Now I won't forget how to do that again!
Ejecting the CDROM · 700 days ago by Dylan Doxey
Well, the CDROM has been open for the last couple of hours.
I did a quick 'man eject' with hope that there's a way to close it without having to get out of my chair.
eject -t
Ah, that's better.
SCP -- The World's Most Convenient File Transfer · 742 days ago by Dylan Doxey
Okay, world's most convenient might be a stretch if you don't do it very often. But if you can force yourself to remember this ...
scp -P 1234 favicon.ico yourself@example.com:/var/www/example.com/htdocs/
That's a relatively convenient way to push your brand new favicon.ico file to the server without all the drudgery of messing around with a GUI FTP client, or the rigmarole adding to your repository, committing, logging in on the server and updating.
And it goes the other way also. Need to fetch a report from your home directory?
scp -P 1234 yourself@example.com:/home/yourself/big_report.csv .
Now that's getting the job done without a lot of distraction!
Note: In your world you're likely change the port number 1234 to something else, or leave out the -P # option altogether.
Happy computing.
Just a Little Program... to be sure. · 808 days ago by Dylan Doxey
Some things are just obviously correct and you go about your business doing things the correct way until one day you realize there's a better way.
For example, you're going about your business, about to populate an array with regex matches and you might wonder, "Does it really need to be done in a loop?"
1 #!/usr/bin/perl -Tw
2
3 use strict;
4 use warnings;
5 use Data::Dumper;
6
7 my $text = "
8 abc123abc
9 abc123abc
10 abc123abc
11 abc123abc
12 ";
13
14 my $regex = qr{ ( \d+ ) }xms;
15
16 {
17 my @matches = $text =~ $regex;
18
19 print 'A: ' . Dumper( \@matches ) . "\n";
20 }
21 {
22 my @matches = $text =~ m/$regex/g;
23
24 print 'B: ' . Dumper( \@matches ) . "\n";
25 }
26 {
27 my @matches;
28 while ( $text =~ m/$regex/g ) {
29
30 push @matches, $1;
31 }
32
33 print 'C: ' . Dumper( \@matches ) . "\n";
34 }
If you're still reading, then it's probably not obvious to you... as it now is to me.
Long story short, here's what you get:
1 A: $VAR1 = [ 2 '123' 3 ]; 4 5 B: $VAR1 = [ 6 '123', 7 '123', 8 '123', 9 '123' 10 ]; 11 12 C: $VAR1 = [ 13 '123', 14 '123', 15 '123', 16 '123' 17 ];
Happy computing.
Permutations · 812 days ago by Dylan Doxey
Last night was was thinking to myself, "Self, I sure would like a list of all the permutations of these characters in a string of size n."
That's the point when I set myself to work and produced this little snippet of code.
1 sub permute {
2 my ($letters_ra,$size) = @_;
3
4 return
5 if not $size;
6
7 my $words_ra = permute( $letters_ra, $size - 1 );
8
9 return $letters_ra
10 if not @{ $words_ra || [] };
11
12 my @words;
13
14 for my $word (@{ $words_ra }) {
15
16 for my $letter (@{ $letters_ra }) {
17
18 push @words, "$letter$word";
19 }
20 }
21
22 return \@words;
23 }
Yea, that gets the job done.
27 # create a list of a-z
28 my @letters = map { chr $_ } ( 97 .. 122 );
29
30 # create a list of all four letter words
31 my $words_ra = permute( \@letters, 4 );
Now that we've got this list laying around, let's see if we can register any of them as domains.
35 use LWP::Simple qw( get );
36
37 WORD:
38 for my $word (@{ $words_ra }) {
39
40 my $json = get( "http://instantdomainsearch.com/services/quick/?name=$word" );
41
42 my ($com,$net,$org) = $json =~ m{'name':'$word','com':'(\w+)','net':'(\w+)','org':'(\w+)'}xms;
43
44 next WORD
45 if "$com$net$org" eq 'uuu';
46
47 print "$word: com:$com, net:$net, org:$org\n";
48 }
That's going to be 264 domain lookups which average around 1 second per. That should take about 42 hours to run.
I've found that just because instantdomainsearch.com reports it as available, doesn't mean it's available.
Happy computing.