Feature #6731

add new method "Object.present?" as a counter to #empty?

Added by Roger Pack about 3 years ago. Updated about 3 years ago.

[ruby-core:46420]
Status:Rejected
Priority:Normal
Assignee:-

Description

Basically Object#present? , "An object is present if it’s not #empty?" [2]
or, in other words, "is there any data inside?"

Examples:

[].present?
=> false
[3].present?
=> true
''.present?
=> false # because it's #empty?
'a'.present?
=> true
nil.present?
=> false

Example usage:

button.text=text if text.present? # I only care whether the text actually was set to something, and also don't want to worry about whether it's nil or not.

Thanks.

Basic implementation ([1]):

class Object

def present?
!(respond_to?(:empty?) ? empty? : !self)
end

end

[1] http://stackoverflow.com/a/4649452/32453
[2] http://api.rubyonrails.org/classes/Object.html#method-i-present-3F they also use #blank but that's for a different feature request.

present.txt Magnifier (868 Bytes) Roger Pack, 07/14/2012 03:39 PM

History

#1 Updated by Roger Pack about 3 years ago

Adding "presentation" txt file.

#2 Updated by Clay Trump about 3 years ago

Hum, wouldn't this conflict with Rails? In Rails, " ".present? is
falseclass Object

def present?
!(respond_to?(:empty?) ? empty? : !self)
end

end

#3 Updated by Yusuke Endoh about 3 years ago

  • Status changed from Open to Rejected

Roger Pack,

Sorry but this proposal was rejected at the developer meeting (7/21).

There are many possible definitions of "present?" depending upon
contexts. It's not Ruby's decision. People should decide the
definition for their context.

Yusuke Endoh mame@tsg.ne.jp

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