V (programming language): Difference between revisions

Revision as of 14:23, 7 July 2025

Revision as of 14:42, 7 July 2025

Line 141:

Optional types are for types which may represent none. Result types may represent an error returned from a function.

Option types are declared by prepending {{code|?}} to the type name: {{code|?Type}}. Result types use {{code|!}}: {{code|!Type}}.<ref name="Knott"/><ref name="section"/>{{Sfn|Tsoukalos|2022}}

<syntaxhighlight lang="V">

fn do_somethingsomething(st string) !string {

if st == "foo" { return "foo" }

return "foo"

}

return error("invalid string")

}

ax := do_somethingsomething("foo") or { "default" } // ax will be "foo"

by := do_somethingsomething("barcar") or { "default" } // by will be "default"

cz := do_somethingsomething("barcar") or { panic("{err}") } // exitswill exit with error "invalid string" and a traceback

println(ax)

println(by)

</syntaxhighlight>