ludic/examples/library/optionresult.ludic
Orkuncakilkaya bf36bc8a8f refactor(runtime,packages,examples): named constants, package enums, idiom sweep
- runtime: HEADLESS_FRAME_PATH, STICK_DEADZONE / STICK_LEFT_X/Y, key and
  byte codes as char literals throughout (`k == 'w'`, `fill(rt_map, ' ', …)`)
- ludic.gameplay/stats: drop the duplicate `stat_field` (it answered "atk"
  for every build stat); Stats.base uses stats_field_name
- ludic.shooter: compare aim modes and fire patterns with AimMode.* and
  WeaponPattern.* instead of raw ints; STICK_RIGHT_X/Y
- ludic.npcai: DecisionMade / brain_set_state use AiState.*
- examples/games/menu.ludic uses Font.load / Ui.* with FONT_PATH and
  BACKDROP named; strings.ludic header says what it prints
- whole tree: `x = x + 1` → `x += 1` (single-term right-hand sides only),
  `0 - x` → `-x`, ASCII codes → char literals; every .ludic and every
  ```ludic fence reformatted with the fixed formatter (whitespace only)

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
2026-09-05 01:12:26 +03:00

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1.4 KiB
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# optionresult.ludic — the safety value types: `option` (some/none, "maybe a
# value") and `result` (ok/err/try, "a value or a failure"). Each assertion that
# holds prints its number, so a full run prints:
# 1 2 3 4 5 6 7 8 9 10 11 12
# option is issue #53; result shipped in #46. Both are additive — a program that
# does not use them compiles byte-identically.
program OptionResult {
# a lookup that may find nothing — no magic -1 sentinel
function slot_of(id: int) -> option {
if id < 0 { return none() }
return some(id * 10)
}
# a fallible parse — a value or a message
function to_digit(c: int) -> result {
if c >= '0' and c <= '9' { return ok(c - 48) } # '0'..'9'
return err("not a digit")
}
entry {
# --- option ---
let a = some(42)
if is_some(a) { print(1) }
if not is_none(a) { print(2) }
if unwrap_or(a, -1) == 42 { print(3) }
let b = none()
if is_none(b) { print(4) }
if unwrap_or(b, -1) == -1 { print(5) }
if unwrap_or(slot_of(5), 0) == 50 { print(6) }
if is_none(slot_of(-1)) { print(7) }
# --- result + try/else ---
if is_ok(to_digit(55)) { print(8) }
if is_err(to_digit(120)) { print(9) }
let d = try to_digit(55) else { 0 } # '7' -> 7
if d == 7 { print(10) }
let bad = try to_digit(120) else { -1 } # not a digit -> fallback
if bad == -1 { print(11) }
let msg = try to_digit(120) else { print(12); 0 } # else binds `error`
}
}