# Module lookup starting with "::"

**URL:** <https://www.ruby-forum.com/t/module-lookup-starting-with/167098>\
**Category:** Ruby\
**Created:** [May 4, 2009, 2:09am UTC](https://www.ruby-forum.com/t/module-lookup-starting-with/167098 "2009-05-04T02:09:36Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![ppjunty](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/aeb1de/32.png) [@ppjunty](https://www.ruby-forum.com/u/ppjunty)\
**Post date:** [May 4, 2009, 2:09am UTC](https://www.ruby-forum.com/t/module-lookup-starting-with/167098/1 "2009-05-04T02:09:36Z")

</div>

hello, could anyone explain why sometimes a module is  
referenced with “::” before its name? like in

:🅰🅱:C

is it equivalent to the regular form “A:🅱:C”?

thanks

---

<div class="post-metadata">

**Author:** ![ppjunty](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/aeb1de/32.png) [@ppjunty](https://www.ruby-forum.com/u/ppjunty)\
**Post date:** [May 4, 2009, 2:27am UTC](https://www.ruby-forum.com/t/module-lookup-starting-with/167098/2 "2009-05-04T02:27:44Z")

</div>

It’s simply saying “do the lookup starting at the global scope and work  
down” instead of “go up the scope hierarchy until you find what I’m  
looking  
for”.  
Useful in the case where you might have similarly named classes in  
differing  
scopes and need to specify exactly which class you want.

Jason

---

<div class="post-metadata">

**Author:** ![ppjunty](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/aeb1de/32.png) [@ppjunty](https://www.ruby-forum.com/u/ppjunty)\
**Post date:** [May 4, 2009, 2:43am UTC](https://www.ruby-forum.com/t/module-lookup-starting-with/167098/3 "2009-05-04T02:43:00Z")

</div>

thanks Jason, very clear explanation.