rand -- Random Number Generator
Syntax: rand subcommand ?args...?
The rand command provides access to the rand crate's thread_rng. It has the
following subcommands.
| Subcommand | Description |
|---|---|
| rand bool | Generates a random boolean |
| rand range | Generates an integer from a range |
| rand sample | Selects an item randomly from a list |
rand bool
Syntax: rand bool ?prob?
Returns either a 1 or 0, both with probability 0.5. If given, prob must be a number between 0.0 and 1.0 indicating the probability of getting a 1.
TODO: Rejects prob if it is exactly 0.0 or 1.0. That might be a nuisance.
rand range
Syntax: rand range ?start? end
Randomly selects and returns a number in the range start to (end - 1). The start value defaults to 0.
rand sample
Syntax: rand sample list...
Randomly selects and returns an element from a list. The list can be provided as a single value, or as multiple elements on the command line, i.e., the two calls shown below both return a random letter "a", "b", "c", "d", or "e".
rand sample a b c d e
set list [list a b c d e]
rand sample $list