→

Success return type and recoverable alternate-exit type in function signatures.

Syntax: functio <name>(<params>) → <type> | functio <name>(<params>) → <success> ⇥ <error>

Category

function

Related

• ⇥
• functio
• redde
• iace
• cape

Examples

examples/corpus/operatores/function-types.fab (canonical · operator-group)

Success return type and recoverable alternate-exit type in function signatures.

# operatores/function-types — → and ⇥
#
# GRAMMAR:
#   funcType :← 'functio' ident '(' params ')' ('→' type)? ('⇥' type)?
#
# EXPECTED OUTPUT:
#   salve, 5, 0
#
# BACKEND:
#   Cross-ref functio/functio.fab and iace/functio-fallibilis.fab.

functio saluta() → textus {
    redde "salve"
}

functio divide(numerus a, numerus b) → numerus ⇥ textus {
    si b ≡ 0 ergo iace "division by zero"
    redde a / b
}

functio tutum(numerus a, numerus b) → numerus {
    fac {
        redde divide(a, b)
    }
    cape err {
        mone err
        redde 0
    }
}

incipit {
    nota saluta()
    nota tutum(10, 2)
    nota tutum(10, 0)
}

Expected output:

salve
5
0