io.put_string_32 ("[ Hello! ¡Hola! Bonjour! こんにちは！ Здравствуйте! Γειά σου! ]")

Unicode output in console

feature -- Access ... invariant all_items_valid: ∀ x: items ¦ x.is_valid at_least_one_marked: ∃ x: items ¦ x.is_marked end

Assertions: class invariants with symbolic notation

 values := << 1, 2, 4, 8 >> -- Sum of (index * values [index]). across values as i from sum := 0 loop sum := sum + i.cursor_index * i.item end

Sum using across loop

 rating := locale.plural_translation_in_context ("$1 star", "$1 stars", "example.context", n) ... rating: READABLE_STRING_32 -- Translated message. locale: I18N_LOCALE -- Currently selected locale with translations. do ... end

Internationalization

class DINING_PHILOSOPHER ... feature -- Basic operations eat (left, right: separate FORK) -- Race-free access to the forks `left` and `right`. do left.use right.use end end

Concurrency with SCOOP

feature -- Access balance: INTEGER -- Current balance in dollars. feature -- Element change withdraw (amount: INTEGER) -- Remove `amount` dollars. require positive: amount > 0 not_too_big: amount <= balance do balance := balance - amount ensure increased: balance = old balance - amount end

Bank account example

run -- Execute tasks from `pool`. do from until not attached retrieved_task (pool) as task loop separate task as t do t.call end end end

Running a pool of tasks

class REFEREE: race_start.publish (create {DATE_TIME}.make_now_utc) class RACE_CONTROL: race_start: EVENT_TYPE [DATE_TIME] class SPRINTER: race_start.subscribe (agent run_from_now) run_from_now (t: DATE_TIME) -- Record `t` as starting time and get running. do start_time := t run end

Event-based programming with agents