Module DataMapper::Sweatshop::Unique
In: lib/dm-sweatshop/unique.rb

Methods

unique  

Classes and Modules

Class DataMapper::Sweatshop::Unique::TooManyTriesException

Public Instance methods

Yields a value to the block. The value is unique for each invocation with the same block. Alternatively, you may provide an explicit key to identify the block.

If a block with no parameter is supplied, unique keeps track of previous invocations, and will continue yielding until a unique value is generated. If a unique value is not generated after @UniqueWorker::MAX_TRIES@, an exception is raised.

ParseTree is required unless an explicit key is provided

  (1..3).collect { unique {|x| x }}     # => [0, 1, 2]
  (1..3).collect { unique {|x| x + 1 }} # => [1, 2, 3]
  (1..3).collect { unique {|x| x }}     # => [3, 4, 5] # Continued on from above
  (1..3).collect { unique(:a) {|x| x }} # => [0, 1, 2] # Explicit key overrides block identity

  a = [1, 1, 1, 2, 2, 3]
  (1..3).collect { unique { a.shift }}  # => [1, 2, 3]
  (1..3).collect { unique { 1 }}        # raises TooManyTriesException

return <Object> the return value of the block

[Validate]