sponte
Translation status: English reader-locale proof. Code fences render through the en pipeline; prose is canonical Latin.
Marks a named declaration slot (parameter or genus field) as voluntary — the caller or provider may omit the value.
Aliases: optional, voluntary
Syntax: <type> <name> sponte [= default | vel default]
Category#
declaration
Related#
Examples#
radix/corpus/sponte/sponte.fab (canonical · keyword)#
Marks a named declaration slot (parameter or genus field) as voluntary — the caller or provider may omit the value.
# =============================================================================
# sponte — Marks a named declaration slot (parameter or genus field) as voluntary — the caller or provider may omit the value.
# =============================================================================
#
# What this teaches:
# • Voluntary parameter syntax — using `sponte` to mark function parameters or genus fields as optional
# • Default values — combining `sponte` with `vel` to provide fallbacks when the value is omitted
#
# Common mistakes:
# • confusing sponte (optional parameter with a default) with ∪ nihil (nullable type) — sponte marks omission, ∪ nihil marks absence
#
# See also: vel, nihil, ∪, functio, genus
# =============================================================================
# sponte — optional parameter / field marker
#
# GRAMMAR:
# optionalMarker :← 'sponte'
#
# EXPECTED OUTPUT:
# No incipit — declaration or test-runner surface only.
#
# BACKEND:
# declaration-only optional slots (whitelist: sponte/sponte.fab). Cross-ref: optionalis/optionalis.fab.
#
fn greet(string nomen, string titulus optional) → string {
return nomen
}
fn paginate(int pagina optional coalesce 1) → string {
return "page"
}
class User {
string name
string email optional
}