Problem with String.my_custom_func! "Can't change the value of self"

ruby-talk
1

Hi all -

I'm extending the String class to include a tidy_up_html() method that runs the string using tidy. Works great. However, I'd like to also have a tidy_up_html!() method and do it in place.

The problem is that the tidy library *has* to return a new value, so at some point I have to do:

   self = ......

at which point I get the error: Can't change the value of self

Here's a trivial example:

class String
     def my_func!
         self.gsub!(/x/, 'y') #okay
         self = result_of_tidy_call #not okay
     end
end

I'm new enough to ruby that I can't figure out how to work around this...

Suggestions?

Thanks!

-philip

2

Hi --

···

On Sat, 22 Apr 2006, Philip Hallstrom wrote:

Hi all -

I'm extending the String class to include a tidy_up_html() method that runs the string using tidy. Works great. However, I'd like to also have a tidy_up_html!() method and do it in place.

The problem is that the tidy library *has* to return a new value, so at some point I have to do:

  self = ......

at which point I get the error: Can't change the value of self

Here's a trivial example:

class String
   def my_func!
       self.gsub!(/x/, 'y') #okay
       self = result_of_tidy_call #not okay
   end
end

I'm new enough to ruby that I can't figure out how to work around this...

Suggestions?

There's a String#replace method:

   s = "abc"
   s.replace("def")

s is now the same object, but with different contents.

David

--
David A. Black (dblack@wobblini.net)
Ruby Power and Light, LLC (http://www.rubypowerandlight.com)

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