Module: WC::Essentials::ClassHelpers

Defined in:
lib/wc/essentials/class_helpers.rb

Overview

Helpers for classes

Class Method Summary collapse

Class Method Details

.assign_class_variable(klass, name, value) ⇒ Object

Assign class variable and also merge parent class variable. Usefull if required to have class variable only bind to the class in the case of inheritence

Parameters:

  • klass (class)
  • name (symbol)
  • value (any) 


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# File 'lib/wc/essentials/class_helpers.rb', line 26

def self.assign_class_variable(klass, name, value)
  klass.ancestors.each do |ancestor|
    value = concat_var(ancestor, name, value)
  end

  k_var_name = klass_var_name(klass, name)
  klass.class_variable_set(k_var_name, value)
end

.concat_var(klass, name, value) ⇒ Object

Concat values from value provided with value assigned to the class variable

Parameters:

  • klass (class)
  • name (symbol)
  • value (any) 


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# File 'lib/wc/essentials/class_helpers.rb', line 41

def self.concat_var(klass, name, value)
  var_name = klass_var_name(klass, name)
  existing = var_value(
    klass,
    var_name,
    value.is_a?(Array) ? [] : {}
  )

  (value.is_a?(Array) ? (existing + value) : value.merge(existing))
end

.klass_var_name(klass, name) ⇒ Object

Get the class variable name

Parameters:

  • klass (class)
  • name (symbol) 


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# File 'lib/wc/essentials/class_helpers.rb', line 11

def self.klass_var_name(klass, name)
  "@@#{
    klass.name.split('::')
      .join('_')
      .downcase
  }_#{name}"
end

.var_value(klass, name, default = []) ⇒ Object

Return the value of class variable

Parameters:

  • klass (class)
  • name (symbol)
  • default (any) (defaults to: []) 


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# File 'lib/wc/essentials/class_helpers.rb', line 58

def self.var_value(klass, name, default = [])
  return default unless defined?(klass.class_variable_get(name))

  klass.class_variable_get(name)
rescue StandardError
  default
end