# Builtin singleton & instance\_methods

**URL:** <https://www.ruby-forum.com/t/builtin-singleton-instance-methods/77183>\
**Category:** Ruby\
**Created:** [November 24, 2006, 11:51pm UTC](https://www.ruby-forum.com/t/builtin-singleton-instance-methods/77183 "2006-11-24T23:51:31Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![lopex](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/e79b87/32.png) [@lopex](https://www.ruby-forum.com/u/lopex)\
**Post date:** [November 24, 2006, 11:51pm UTC](https://www.ruby-forum.com/t/builtin-singleton-instance-methods/77183/1 "2006-11-24T23:51:31Z")

</div>

Hi,

given:

s=“some string”

def s.some\_meth  
end

class \<\< s  
p self.instance\_methods(false)  
end

why instance\_methods doesn’t return only the name of a method defined  
for singletons class ? I’ve found that this is also true for other  
builtin types that have _basic_ structure. I’ve also looked into  
ins\_methods\_push and class\_instance\_method\_list in Ruby sources, but  
haven’t found any clues…

JRuby behaves the expected way…

lopex