Where did this constant come from?

[David Masover]

What's the simplest way to find out where a constant was defined?

I did come up with a way (probably partly ripped off from ActiveSupport), but
it feels convoluted and fragile:


class Module
def parent_namespace
parts = self.name.split('::')
if parts.length > 1
parts.tap(&op).join('::').constantize
else
nil
end
end

def eldest_ancestor_with_const name
if const_defined? name
klass = self
self.ancestors.each do |ancestor|
break if klass == Object
break unless ancestor.const_defined? name
klass = ancestor
end
klass
else
nil
end
end

def find_const_parent name
if Object.const_defined? name
Object
else
klass = self
until klass.const_defined? name
klass = klass.parent_namespace
return nil if klass.nil?
end

klass.eldest_ancestor_with_const(name)
end
end
end

 

[Heesob Park]

Hi,

What's the simplest way to find out where a constant was defined?

I did come up with a way (probably partly ripped off from ActiveSupport), but
it feels convoluted and fragile:


class Module
def parent_namespace
parts = self.name.split('::')
if parts.length > 1
parts.tap(&op).join('::').constantize
else
nil
end
end

def eldest_ancestor_with_const name
if const_defined? name
klass = self
self.ancestors.each do |ancestor|
break if klass == Object
break unless ancestor.const_defined? name
klass = ancestor
end
klass
else
nil
end
end

def find_const_parent name
if Object.const_defined? name
Object
else
klass = self
until klass.const_defined? name
klass = klass.parent_namespace
return nil if klass.nil?
end

klass.eldest_ancestor_with_const(name)
end
end
end

Something like this:

def find_const_parent(name)
Object.constants.select do |x|
x=eval(x)
[Class,Module].include?(x.class) && x.const_defined?(name)
end
end


Regards,

Park Heesob

 

[Ilan Berci]

What's the simplest way to find out where a constant was defined?

I did come up with a way (probably partly ripped off from
ActiveSupport), but
it feels convoluted and fragile:

just install the gem rak and grep for it..


I do this all the time when I have to go into AR..
cd /usr/lib/ruby/gems/1.8/gems/activerecord/lib
rak <constant_name>

done