اختياري

Marks a named declaration slot (parameter or صنف field) as voluntary — the caller or provider may omit the value.

Aliases: optional, voluntary

Syntax: <type> <name> اختياري [= default | عوض default]

Category#

declaration

Related#

• عوض
• لاشيء
• ∪
• دالة
• صنف

Examples#

radix/corpus/sponte/sponte.fab (canonical · keyword)#

Marks a named declaration slot (parameter or صنف field) as voluntary — the caller or provider may omit the value.

# =============================================================================
# اختياري — Marks a named declaration slot (parameter or صنف field) as voluntary — the caller or provider may omit the value.
# =============================================================================
#
# What this teaches:
#   • Voluntary parameter syntax — using `اختياري` to mark function parameters or صنف fields as optional
#   • Default values — combining `اختياري` with `vel` to provide fallbacks when the value is omitted
#
# Common mistakes:
#   • confusing اختياري (optional parameter with a default) with ∪ نوع_لاشيء (nullable type) — اختياري marks omission, ∪ نوع_لاشيء marks absence
#
# See also: vel, نوع_لاشيء, ∪, دالة, صنف
# =============================================================================



# اختياري — optional parameter / field marker
#
# GRAMMAR:
#   optionalMarker :← 'اختياري'
#
# EXPECTED OUTPUT:
#   No بداية — declaration or test-runner surface only.
#
# BACKEND:
#   declaration-only optional slots (whitelist: اختياري/sponte.fab). Cross-ref: optionalis/optionalis.fab.
#

fn greet(string اسم, string titulus optional) → string {
    return اسم
}

fn paginate(int pagina optional coalesce 1) → string {
    return "page"
}

class User {
    var string name
    var string email optional
}