Method: Mixture::Extensions::Hashable#fetch

Defined in:

lib/mixture/extensions/hashable.rb

#fetch(key) ⇒ Object #fetch(key, default) ⇒ Object #fetch(key) {|key| ... } ⇒ Object

Overloads:

• #fetch(key) ⇒ Object

  Performs a fetch. This acts just like Hash's fetch.

  Parameters:

  • key (Symbol) —

    The key to check for an attribute.

  Returns:

  • (Object) —

    The attribute's value.

  Raises:

  • (KeyError) —

    If the key isn't present.

• #fetch(key, default) ⇒ Object

  Performs a fetch. This acts just like Hash's fetch. If the attribute doesn't exist, the default argument value is used as a value instead.

  Parameters:

  • key (Symbol) —

    The key to check for an attribute.

  • default (Object) —

    The value to use instead of an error.

  Returns:

  • (Object) —

    The attribute's value, or the default value instead.

• #fetch(key) {|key| ... } ⇒ Object

  Performs a fetch. This acts just like Hash's fetch. If the attribute doesn't exist, the value of the block is used as a value instead.

  Parameters:

  • key (Symbol) —

    The key to check for an attribute.

  Yields:

  • (key) —

    The block is called if an attribute does not exist.

  Yield Parameters:

  • key (Symbol) —

    The key of the non-existant attribute.

  Yield Returns:

  • (Object) —

    Return value of the method.

  Returns:

  • (Object) —

    The attribute's value, or the block's value instead.

# File 'lib/mixture/extensions/hashable.rb', line 85

def fetch(key, default = Undefined)
  if key?(key.to_s.intern) then attribute(key.to_s.intern)
  elsif block_given?          then yield(key.to_s.intern)
  elsif default != Undefined  then default
  else fail KeyError, "Undefined attribute #{key.to_s.intern}"
  end
end