System library

These built-ins reach outside the program: the filesystem, the clock, the OS environment, and external processes. They're always available (no import).

File I/O

Function	Description
`read_file(path)`	Whole file as a string.
`read_lines(path)`	List of lines (newlines stripped).
`write_file(path, text)`	Write `text`, truncating the file.
`append_file(path, text)`	Append `text` to the file.
`file_exists(path)`	`true` if the path exists.
`remove_file(path)`	Delete a file; returns whether it was removed.
`make_dir(path)`	Create a directory (and parents); returns whether it was created.
`list_dir(path)`	List of entry names in a directory.

write_file("notes.txt", "hello\nworld\n")
print(read_lines("notes.txt"))     # ["hello", "world"]
if file_exists("notes.txt") { remove_file("notes.txt") }

Time & date

Function	Description
`clock()`	Monotonic seconds - use for measuring elapsed time.
`time()`	Seconds since the Unix epoch (with fraction).
`now()`	Local date/time as a dict: `year, month, day, hour, minute, second, weekday, yearday`.
`format_time(fmt[, epoch])`	Format with `strftime` codes (e.g. `"%Y-%m-%d %H:%M"`).
`sleep(seconds)`	Pause; releases the lock so other threads run.

let t0 = clock()
heavy_work()
print("took", clock() - t0, "seconds")
print(format_time("%Y-%m-%d"))     # 2026-08-05

Random

Function	Description
`random()`	Float in `[0, 1)`.
`random_int(a, b)`	Integer in `[a, b]` inclusive.
`random_range(a, b)`	Float in `[a, b)`.
`random_choice(list)`	A random element.
`random_seed(n)`	Seed the generator (same seed ⇒ same sequence).

random_seed(42)
print(random_int(1, 6))            # a dice roll, reproducible
print(random_choice(["red", "green", "blue"]))

Environment & arguments

Function	Description
`env(name[, default])`	Environment variable, or `default` / `nil`.
`set_env(name, value)`	Set an environment variable.
`args()`	List of command-line arguments after the script path.

./bee script.bee alpha beta      # args() == ["alpha", "beta"]
print(env("HOME"))
print(env("MISSING", "n/a"))

Processes

Function	Description
`exec(cmd)`	Run `cmd` in the shell; returns `{"code": exit_status, "output": stdout}`.

let r = exec("ls -1")
if r.code == 0 {
    for line in r.output.trim().split("\n") { print(line) }
}