method

safe_constantize

v3.2.8 - Show latest stable - Class: ActiveSupport::Inflector

safe_constantize(camel_cased_word)

public

Tries to find a constant with the name specified in the argument string:

"Module".safe_constantize     # => Module
"Test::Unit".safe_constantize # => Test::Unit

The name is assumed to be the one of a top-level constant, no matter whether it starts with “::” or not. No lexical context is taken into account:

C = 'outside'
module M
  C = 'inside'
  C                    # => 'inside'
  "C".safe_constantize # => 'outside', same as ::C
end

nil is returned when the name is not in CamelCase or the constant (or part of it) is unknown.

"blargle".safe_constantize  # => nil
"UnknownModule".safe_constantize  # => nil
"UnknownModule::Foo::Bar".safe_constantize  # => nil

# File activesupport/lib/active_support/inflector/methods.rb, line 258
    def safe_constantize(camel_cased_word)
      begin
        constantize(camel_cased_word)
      rescue NameError => e
        raise unless e.message =~ /(uninitialized constant|wrong constant name) #{const_regexp(camel_cased_word)}$/ ||
          e.name.to_s == camel_cased_word.to_s
      rescue ArgumentError => e
        raise unless e.message =~ /not missing constant #{const_regexp(camel_cased_word)}\!$/
      end
    end

safe_constantize

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