# Solutions for deep class paths

**URL:** <https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042>\
**Category:** Ruby\
**Created:** [January 17, 2007, 12:27am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042 "2007-01-17T00:27:16Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 12:27am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/1 "2007-01-17T00:27:16Z")

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Hi all,

I’ve currently got a very flat code structure in a large code base  
[1], and I’m looking at redoing the layout to make the functional  
lines more obvious. This redesign will add an extra constant to  
every class path; e.g., where I might have ‘Puppet::Type::User’ right  
now, I’d have ‘Puppet::OSAL::Type::User’ in the new layout.

If possible, I’d like to avoid having to type full class paths every  
time I talk about a class. I’ve noticed that Ruby behaves very  
differently depending on how I define a class; for instance:

class One  
class Two  
end  
end

will allow Two to use unqualified constants from One, but

class One::Two  
end

will not. This is fine for shallow class paths, but it gets annoying  
when every single class I define has to look like this:

module Puppet  
module OSAL  
class Type  
class User  
…  
end  
end  
end  
end

I’d _much_ prefer to just write:

module Puppet::OSAL::Type::User  
end

But if I do that, then I’ll always have to specify the full class  
path. I have quite a few classes in Puppet, and having to include  
the full wrappers for every constant in the class path would get very  
painful, and I would have to be very conscious of load order (because  
every class in Puppet::OSAL::Type would either have to specify type’s  
parent class if there is one, or it would have to be loaded after  
Puppet::OSAL::Type was loaded).

Are there semi-standard ways of making deep class paths more  
convenient to use?

Thanks,  
Luke

1 - [http://reductivelabs.com/projects/puppet](http://reductivelabs.com/projects/puppet)

## – Someday I want to be rich. Some people get so rich they lose all respect for humanity. That’s how rich I want to be. --Rita Rudner

Luke K. | [http://reductivelabs.com](http://reductivelabs.com) | [http://madstop.com](http://madstop.com)

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<div class="post-metadata">

**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 2:20am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/2 "2007-01-17T02:20:29Z")

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On Jan 17, 10:26 am, Luke K. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote, in part:

> end  
> end
> 
> I’d _much_ prefer to just write:
> 
> module Puppet::OSAL::Type::User  
> end

module Puppet; module OSAL; class Type  
class User  
…  
end  
end

That’s all I can think of.

Cheers,  
Gavin

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<div class="post-metadata">

**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 4:39am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/3 "2007-01-17T04:39:43Z")

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On Jan 16, 2007, at 6:26 PM, Luke K. wrote:

> I’d _much_ prefer to just write:
> 
> module Puppet::OSAL::Type::User  
> end
> 
> But if I do that, then I’ll always have to specify the full class  
> path.

Can you group all the constants in a module? Something like this:

module Puppet

module Constants  
Constant1 = 42  
Constant2 = Constant1 \* 42  
end

module OSAL  
module Type  
end  
end

class OSAL::Type::User  
include Constants # Now the constants can be used unqualified

```
 puts Constant1

```

end

class OSAL::Type::User2  
include Constants # Now the constants can be used unqualified

```
 puts Constant2

```

end  
end

Gary W.

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<div class="post-metadata">

**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 5:22am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/4 "2007-01-17T05:22:58Z")

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On Jan 17, 2007, at 2:39 PM, removed\_email\_address@domain.invalid wrote:

> module OSAL  
> class OSAL::Type::User2  
> include Constants # Now the constants can be used unqualified
> 
> ```
> puts Constant2
> 
> ```
> 
> end  
> end

Well, the constants in this case are all of the class constants, not  
arbitrary constants like numbers. So, if I did this, I’d have to  
stick a constant for each class into that Constants module.

## – Risk! Risk anything! Care no more for the opinions of others, for those voices. Do the hardest thing on earth for you. Act for yourself. Face the truth. – Katherine Mansfield

Luke K. | [http://reductivelabs.com](http://reductivelabs.com) | [http://madstop.com](http://madstop.com)

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**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 5:48am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/5 "2007-01-17T05:48:00Z")

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On Jan 16, 2007, at 11:21 PM, Luke K. wrote:

> Well, the constants in this case are all of the class constants,  
> not arbitrary constants like numbers. So, if I did this, I’d have  
> to stick a constant for each class into that Constants module.

If each class has its own collection of constants, why aren’t you  
putting the definitions right in the class? In your original post it  
sounded like you were looking for a way to have several different  
classes have ‘direct’ access to a common collection of constants  
(i.e. without the need for explicit scoping).

Gary W.

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<div class="post-metadata">

**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 6:58am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/6 "2007-01-17T06:58:06Z")

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On Jan 17, 2007, at 3:46 PM, removed\_email\_address@domain.invalid wrote:

> constants (i.e. without the need for explicit scoping).  
> Well, that’s kind of what I want, except that in this case the  
> constants are those associated with my classes and modules. E.g.,  
> the constants in question are ‘Puppet’ (which points to the Puppet  
> module) and Puppet::OSAL::Type (which points to the Type class in  
> Puppet::OSAL).

There’s probably a better way to talk about this, I suppose. What I  
really want is to have access to all of the classes in Puppet without  
having to specify quite so long a constant path everywhere and also  
without having to have all of my classes wrapped in four or five  
module/end statements.

## – If a dog jumps onto your lap it is because he is fond of you; but if a cat does the same thing it is because your lap is warmer. – Alfred North Whitehead

Luke K. | [http://reductivelabs.com](http://reductivelabs.com) | [http://madstop.com](http://madstop.com)

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**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 5:20am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/7 "2007-01-17T05:20:58Z")

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On Jan 17, 2007, at 12:20 PM, Gavin S. wrote:

> module Puppet; module OSAL; class Type  
> class User  
> …  
> end  
> end
> 
> That’s all I can think of.

This still requires a bunch of end statements:

module Puppet; module OSAL; class Type  
class User  
…  
end  
end; end; end

Not the worst, I guess, but it’d be nice if I could just manipulate  
the constant lookup path or something.

## – The time to repair the roof is when the sun is shining. – John F. Kennedy

Luke K. | [http://reductivelabs.com](http://reductivelabs.com) | [http://madstop.com](http://madstop.com)

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<div class="post-metadata">

**Author:** ![lynxinator](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/848f3c/32.png) [@lynxinator](https://www.ruby-forum.com/u/lynxinator)\
**Post date:** [January 17, 2007, 10:04am UTC](https://www.ruby-forum.com/t/solutions-for-deep-class-paths/82042/8 "2007-01-17T10:04:31Z")

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Luke K. \<luke [madstop.com](http://madstop.com)\> writes:

> and also  
> without having to have all of my classes wrapped in four or five  
> module/end statements.

Personally, I don’t see this as a bad thing. I would say it’s a good  
idea to use  
nesting to show, uh, how classes and modules are nested. In any case, it  
only  
happens once per file.