Today I Learned

hashrocket A Hashrocket project

Ruby Regex Supports Interpolation

Today we built a Ruby regex that included an interpolated string. It looked like this:

# app/models/developer.rb
validates :email, format: { with: /\A.+@(#{ENV['permitted_domains']})\z/ }

This allows permitted_domains to be customized as an environmental variable:

# config/application.yml
permitted_domains: '|'

The parens and pipe allow us to white-list multiple domains in a single environmental variable.

See More #ruby TILs
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