From: Morton Goldberg <m_goldberg@...>
Date: 2007-07-20T09:19:35+09:00
Subject: Re: regex backreference weirdness...

On Jul 19, 2007, at 6:23 PM, Kyle Schmitt wrote:

> Below is what I tried, which leads me up to the question of... what
> would the _right_ way be of doing this?
>
> irb>"camel_case".gsub(/_(.)/,$1.upcase)
> NoMethodError: undefined method `upcase' for nil:NilClass
>        from (irb):1

I think, in this case, you will have to use a block. For example:

    "camel_case".gsub(/_(.)/) { $1.upcase } # => "camelCase"

or

    "camel_case".gsub(/_./) { |m| m[1, 1].upcase } # => "camelCase"

Regards, Morton