Text* Snippets: ruby code

HTML stripper

// description of your code here

str = <<HTML_TEXT
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<html>
<body>
  <h1>Application error</h1>
  <p>Change this error message for exceptions thrown outside of an action (like 
in Dispatcher setups or broken Ruby code) in public/500.html</p>
</body>
</html>
HTML_TEXT

puts str.gsub(/<\/?[^>]*>/, "")

to ruby html strip by minofare on Jan 15, 2008 1 Comments

Calculate the number of working days between two dates

Function

   # wdays is an array with the days of the week
   # to exclude days (eg: wdays = [0,6] for sunday and saturday )

   def calculate_working_days(d1,d2,wdays)
        diff = d2 - d1
        holidays = 0
        ret = (d2-d1).divmod(7)
        holidays =  ret[0].truncate * wdays.length
        d1 = d2 - ret[1]
        while(d1 <= d2)
                if wdays.include?(d1.wday)
                        holidays += 1
                end
                d1 += 1
        end
        diff - holidays
   end

Iterates over date range.

d1 = Date.new( 2006, 12, 1 )

d2 = Date.new( 2007, 1, 15 )

weekdays = (d1..d2).reject { |d| [0,6].include? d.wday }

weekdays.length

to ruby date day guide weekend work by minofare on Sep 12, 2007

Substrings in Ruby

The other day I was wondering why some really simple Ruby code of mine wasn’t working. The code under test looked something like this:

    def find_directories
        directories = []
        entries = `ls -l`.split/\n/  # get long-format directory listing
        entries.shift   # toss away the totals line
        entries.each do |entry|
            is_directory = (entry[0] == 'd')  # is it a directory?
            directories &lt;&lt; dir if is_directory
        end
        directories
    end

I figured that my ls -l.split/\n/ trickery wasn’t working. So I fired up irb and tried it manually. It worked fine.
Then I sprinkled a few puts statements throughout. entries was fine, and each entry was perfect, looking something like this:

drwx------ 24 jcohen jcohen 816 Aug 19 11:04 Documents

I couldn’t figure out what was wrong. All I had to do was look at the first character of entry; if it was a ‘d’, then I knew I had a directory. But for some reason, is_directory was always false. I googled, checked the RDocs for the String class, thumbed through the PickAxe, and something I read triggered one of those ah-ha moments.
Rats: My C# brain is still alive and kicking.

To confirm my fears, I fired up irb again:

irb> s = "Jeff" 
=> "Jeff" 
irb> s[0]
=> 74

That’s right, folks: on a string, the bracket syntax – when given only one parameter – will return the ASCII value of the character inside. Not the actual character, as it will in C#.
To correctly grab a one-character substring from a string, you have to supply two parameters:

irb> s[0,1]
=> "J"

to ruby code string letter substring by minofare on Aug 20, 2007

Related Tags

minofare's Tags

Never been to TextSnippets before?

About this user

HTML stripper

Calculate the number of working days between two dates

Substrings in Ruby