# `Diffo.Uuid`
[🔗](https://github.com/diffo-dev/diffo/blob/v0.9.0/lib/diffo/helpers/uuid.ex#L5)

Validate and/or create Uuid

# `expect_trailing_uuid4`

Callback function for outstanding to expect trailing uuid4.
## Examples
  iex> Diffo.Uuid.expect_trailing_uuid4("serviceInventoryManagement/v4/service/d2566874-d5ee-400b-9983-10d63ec52f32")
  nil

  iex> Diffo.Uuid.expect_trailing_uuid4("serviceInventoryManagement/v4/service/d2566874-d5ee-400b-9983")
  :trailing_uuid4

  iex> Diffo.Uuid.expect_trailing_uuid4("d2566874-d5ee-400b-9983-10d63ec52f32")
  nil

  iex> Diffo.Uuid.expect_trailing_uuid4(nil)
  :trailing_uuid4

# `expect_uuid4`

Callback function for outstanding to expect uuid4.
## Examples

  iex> Diffo.Uuid.expect_uuid4("d2566874-d5ee-400b-9983-10d63ec52f32")
  nil

  iex> Diffo.Uuid.expect_uuid4("serviceInventoryManagement/v4/service/d2566874-d5ee-400b-9983-10d63ec52f32")
  :uuid4

  iex> Diffo.Uuid.expect_uuid4(nil)
  :uuid4

# `trailing_uuid4`

Returns trailing uuid4 if valid, or nil.
## Examples
  iex> Diffo.Uuid.trailing_uuid4("serviceInventoryManagement/v4/service/d2566874-d5ee-400b-9983-10d63ec52f32")
  "d2566874-d5ee-400b-9983-10d63ec52f32"

  iex> Diffo.Uuid.trailing_uuid4("serviceInventoryManagement/v4/service/d2566874-d5ee-400b-9983")
  nil

  iex> Diffo.Uuid.trailing_uuid4("d2566874-d5ee-400b-9983-10d63ec52f32")
  "d2566874-d5ee-400b-9983-10d63ec52f32"

  iex> Diffo.Uuid.trailing_uuid4(nil)
  nil

# `uuid4`

Generates a uuid4

# `uuid4`

Ensures the supplied uuid is valid uuid4, if not creates one.
## Examples
  iex> validated = Diffo.Uuid.uuid4("4cc5b107-0ff3-4bda-80e1-e4264cbaf868")
  iex> validated
  "4cc5b107-0ff3-4bda-80e1-e4264cbaf868"

  iex> generated = Diffo.Uuid.uuid4(nil)
  iex> valid = Diffo.Uuid.uuid4?(generated)
  iex> valid
  true

# `uuid4?`

Tests whether the uuid is uuid4.
## Examples
  iex> Diffo.Uuid.uuid4?("746e465b-3969-460a-980f-af69c9ab248a")
  true

  iex> Diffo.Uuid.uuid4?("9a4cdc44-ca5a-11ef-9cd2-0242ac120002")
  false

  iex> Diffo.Uuid.uuid4?(nil)
  false

# `uuid4_or_nil?`

Tests whether the uuid is uuid4 or nil.
## Examples
  iex> Diffo.Uuid.uuid4_or_nil?("746e465b-3969-460a-980f-af69c9ab248a")
  true

  iex> Diffo.Uuid.uuid4_or_nil?("9a4cdc44-ca5a-11ef-9cd2-0242ac120002")
  false

  iex> Diffo.Uuid.uuid4_or_nil?(nil)
  true

---

*Consult [api-reference.md](api-reference.md) for complete listing*