# uuid/valid? Test whether a value is a well-formed canonical UUID string. Accepts lowercase and uppercase hex; any version/variant nibble passes. Non-string values return `false` (no error). ## Syntax 
[uuid/valid? $s]
## Parameters - `$s` — Value to test ## Examples 
[uuid/valid? "598a1910-0eb9-43b0-86dc-aa7112972fa0"]   # true
[uuid/valid? "F47AC10B-58CC-4372-A567-0E02B2C3D479"]   # true (uppercase)
[uuid/valid? [uuid/nil]]                                # true
[uuid/valid? "598a1910-0eb9-43b0"]                      # false (too short)
[uuid/valid? "598a1910-0eb9-43b0-86dc-aa7112972fa0z"]   # false (bad char)
[uuid/valid? 42]                                        # false (not a string)
## Returns `true` when the value is exactly 36 characters in canonical `8-4-4-4-12` hyphenated form with hex digits elsewhere; otherwise `false`. ## Notes This is a format check only — it does not verify the version or variant nibbles, so UUIDs of any version (v1–v8) and the nil UUID all validate. ## See Also `uuid/v4`, `uuid/v7`, `uuid/nil`
← uuid/v7