Method: Object#presence

Defined in:
lib/active_support/core_ext/object/blank.rb

#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/active_support/core_ext/object/blank.rb', line 35

def presence
  self if present?
end