Convert string to a function in ruby-on-rails

ruby, ruby-on-rails, ruby-on-rails-3

Solution

You can use `instance_eval`:

function = "(a/b)*100"
a = 25.0
b = 50

instance_eval function
# => 50.0

Be aware though that using eval is inherently insecure, especially if you use external input, as it may contain injected malicious code.

Also note that `a` is set to `25.0` instead of `25`, since if it is an integer `a/b` would result in `0` (integer).

Problem

I need a method that through an input string to do a calculation, like this ``` function = "(a/b)*100" a = 25 b = 50 function.something >> 50 ``` have some method for it?

Original source