Module: Hoss::Util::Inflector
Overview
Instance Method Summary collapse
-
#constantize(camel_cased_word) ⇒ Object
Tries to find a constant with the name specified in the argument string.
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#safe_constantize(camel_cased_word) ⇒ Object
Tries to find a constant with the name specified in the argument string.
Instance Method Details
#constantize(camel_cased_word) ⇒ Object
Tries to find a constant with the name specified in the argument string.
constantize('Module') # => Module
constantize('Foo::Bar') # => Foo::Bar
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'
constantize('C') # => 'outside', same as ::C
end
NameError is raised when the name is not in CamelCase or the constant is unknown.
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# File 'lib/hoss/util/inflector.rb', line 46 def constantize(camel_cased_word) names = camel_cased_word.split("::".freeze) # Trigger a built-in NameError exception including the ill-formed constant in the message. Object.const_get(camel_cased_word) if names.empty? # Remove the first blank element in case of '::ClassName' notation. names.shift if names.size > 1 && names.first.empty? names.inject(Object) do |constant, name| if constant == Object constant.const_get(name) else candidate = constant.const_get(name) next candidate if constant.const_defined?(name, false) next candidate unless Object.const_defined?(name) # Go down the ancestors to check if it is owned directly. The check # stops when we reach Object or the end of ancestors tree. constant = constant.ancestors.inject(constant) do |const, ancestor| break const if ancestor == Object break ancestor if ancestor.const_defined?(name, false) const end # owner is in Object, so raise constant.const_get(name, false) end end end |
#safe_constantize(camel_cased_word) ⇒ Object
Tries to find a constant with the name specified in the argument string.
safe_constantize('Module') # => Module
safe_constantize('Foo::Bar') # => Foo::Bar
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'
safe_constantize('C') # => 'outside', same as ::C
end
nil
is returned when the name is not in CamelCase or the constant (or part of it) is unknown.
safe_constantize('blargle') # => nil
safe_constantize('UnknownModule') # => nil
safe_constantize('UnknownModule::Foo::Bar') # => nil
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# File 'lib/hoss/util/inflector.rb', line 99 def safe_constantize(camel_cased_word) constantize(camel_cased_word) rescue NameError => e raise if e.name && !(camel_cased_word.to_s.split("::").include?(e.name.to_s) || e.name.to_s == camel_cased_word.to_s) rescue ArgumentError => e raise unless /not missing constant #{const_regexp(camel_cased_word)}!$/.match(e.) end |