SWI-Prolog -- random_member/2

Documentation
- Reference manual
  - The SWI-Prolog library
    - library(random): Random numbers
- Packages

Availability::- use_module(library(random)).(can be autoloaded)

Source

[semidet]random_member(-X, +List:list)

X is a random member of List. Equivalent to random_between(1, |List|), followed by nth1/3. Fails of List is the empty list.

Compatibility: Quintus and SICStus libraries.