ordo

Declares an enumeration.

Aliases: enum

Syntax: ordo <name> <block>

Category#

type

Related#

• discretio

Examples#

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

Declares an enumeration.

# =============================================================================
# ordo — Declares an enumeration.
# =============================================================================
#
# What this teaches:
#   • Enumeration declaration — `ordo <Name> { member, ... }` declares a set of ordered, named constants.
#   • Discriminant values — Members can have explicit numeric values with `= <number>`.
#   • Pattern matching — `elige` with `casu` branches selects on ordo variants.
#
# Common mistakes:
#   • Confusing ordo (enum with named constants) with discretio (tagged union with payloads) — ordo members carry no data.
#
# See also: discretio
# =============================================================================

# ordo — enumerated constants (ordered variants)
#
# ordo <Nomen> { <membrum>, … }
# ordo <Nomen> { <membrum> = <valor>, … }
#
# GRAMMAR:
#   ordoDecl :← 'ordo' ident '{' ordoMember (',' ordoMember)* '}'
#
# EXPECTED OUTPUT:
#   rubrum
#   actum

enum Color { rubrum, viridis, caeruleum }

enum Condicio { pendens = 0, actum = 1, finitum = 2 }

main {
    # Using ordo values
    const _ color ← Color.rubrum
    const _ condicio ← Condicio.actum

    # Select by ordo
    switch color {
        case Color.rubrum {
            print "rubrum"
        }
        case Color.viridis {
            print "viridis"
        }
        case Color.caeruleum {
            print "caeruleum"
        }
    }

    # Select by ordo with numeric values
    switch condicio {
        case Condicio.pendens {
            print "pendens"
        }
        case Condicio.actum {
            print "actum"
        }
        case Condicio.finitum {
            print "finitum"
        }
    }
}

Expected output:

rubrum
actum