# Using a variable as a method name? **URL:** \ **Category:** Ruby\ **Created:** [February 24, 2008, 2:19am UTC](https://www.ruby-forum.com/t/using-a-variable-as-a-method-name/130001 "2008-02-24T02:19:09Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Phy\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/a587f6/32.png) [@Phy\_P](https://www.ruby-forum.com/u/Phy_P)\ **Post date:** [February 24, 2008, 2:19am UTC](https://www.ruby-forum.com/t/using-a-variable-as-a-method-name/130001/1 "2008-02-24T02:19:09Z")
Hello, I need a bit of help understanding how to use a variable as a name for a method call. Forgive me trying to explains this, I am new at all this. In the code listed, I am tring to set the debugging level of the Logger class, however, the variable in question is not being sustituted prior to interpreting the method call. when “–debug” if($DEBUG\_LEVELS.include?(arg)) mylog.level = Logger::arg ^^^^^^^^^^^ else puts “Debug level can be one of: DEBUG, INFO, WARN, or ERROR” dis\_help end This causes Ruby to spit out that there is no method called arg which is correct. So how do I get arg to be substituted to the value rather than the var name? I tried dereferencing and using the it within a string (okay, a dumb idea). Any way, any help will be much appreciated! TIA! Phy ``` ____________________________________________________________________________________ ``` Looking for last minute shopping deals? Find them fast with Yahoo! Search. [http://tools.search.yahoo.com/newsearch/category.php?category=shopping](http://tools.search.yahoo.com/newsearch/category.php?category=shopping) ---
**Author:** ![Phy\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/a587f6/32.png) [@Phy\_P](https://www.ruby-forum.com/u/Phy_P)\ **Post date:** [February 24, 2008, 2:24am UTC](https://www.ruby-forum.com/t/using-a-variable-as-a-method-name/130001/2 "2008-02-24T02:24:25Z")
Try Logger.send(arg) ---
**Author:** ![Phy\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/a587f6/32.png) [@Phy\_P](https://www.ruby-forum.com/u/Phy_P)\ **Post date:** [February 24, 2008, 2:36am UTC](https://www.ruby-forum.com/t/using-a-variable-as-a-method-name/130001/3 "2008-02-24T02:36:43Z")
On Sat, Feb 23, 2008 at 7:18 PM, Phy P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > This causes Ruby to spit out that there is no method > called arg which is correct. So how do I get arg to > be substituted to the value rather than the var name? > I tried dereferencing and using the it within a string > (okay, a dumb idea). Any way, any help will be much > appreciated! What is the /type/ of arg? If it’s a Proc, you might try arg.call(). If you’re trying to do it via string, look into eval. Jay Fields has some thoughts: > **[Ruby eval with a binding](http://blog.jayfields.com/2006/07/ruby-eval-with-binding.html)** > > I recently discussed how you can evaluate blocks in different scopes by using instance\_eval, yield, and block.call. In this entry I'll sho... > **[Ruby Block Scope](http://blog.jayfields.com/2006/07/ruby-block-scope.html)** > > While doing DSL work you constantly evaluate blocks (or code as strings) in various contexts . In fact, one key to using a DSL is the abili... I seem to remember seeing a better reference, only I can’t recall by whom or where. Regards, Sam ---
**Author:** ![Phy\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/a587f6/32.png) [@Phy\_P](https://www.ruby-forum.com/u/Phy_P)\ **Post date:** [February 24, 2008, 2:46am UTC](https://www.ruby-forum.com/t/using-a-variable-as-a-method-name/130001/4 "2008-02-24T02:46:43Z")
Hi, On Sun, Feb 24, 2008 at 12:23 PM, Corey H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Try Logger.send(arg) In the case of Rails, `arg’ should also be lower case. Is it Logger.warn or .warning? Logger.send(arg.downcase) Arlen