Class: Object

Inherits:
BasicObject
Defined in:
lib/core_ext/object/blank.rb

Overview

this is taken directly from activesupport 3.1.1 we won’t redo all this unless we need to

Instance Method Summary collapse

Instance Method Details

#blank? ⇒ Boolean

An object is blank if it’s false, empty, or a whitespace string. For example, “”, “ ”, nil, [], and {} are all blank.

This simplifies:

if address.nil? || address.empty?

…to:

if address.blank?

Returns:

  • (Boolean) 


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# File 'lib/core_ext/object/blank.rb', line 15

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

#presence ⇒ Object

Returns object if it’s present? otherwise returns nil. object.presence is equivalent to object.present? ? object : nil.

This is handy for any representation of objects where blank is the same as not present at all. For example, this simplifies a common check for HTTP POST/query parameters:

state   = params[:state]   if params[:state].present?
country = params[:country] if params[:country].present?
region  = state || country || 'US'

…becomes:

region = params[:state].presence || params[:country].presence || 'US'



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# File 'lib/core_ext/object/blank.rb', line 38

def presence
  self if present?
end

#present? ⇒ Boolean

An object is present if it’s not blank?.

Returns:

  • (Boolean) 


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# File 'lib/core_ext/object/blank.rb', line 20

def present?
  !blank?
end