In Ruby, can you perform string interpolation on data read from a file?

Question

In Ruby you can reference variables inside strings and they are interpolated at runtime.

For example if you declare a variable foo equals \"Ted\

Answer 1

The 2 most obvious answers have already been given, but if they don't to it for some reason, there's the format operator:

>> x = 1
=> 1
>> File.read('temp') % ["#{x}", 'saddle']
=> "The number of horses is 1, where each horse has a saddle\n"

where instead of the #{} magic you have the older (but time-tested) %s magic ...