v/vlib/builtin/option.v

38 lines
731 B
V
Raw Normal View History

2019-06-23 04:21:30 +02:00
// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
2019-06-22 20:20:28 +02:00
module builtin
struct Option {
data [255]byte
error string
ok bool
is_none bool
2019-06-22 20:20:28 +02:00
}
// `fn foo() ?Foo { return foo }` => `fn foo() ?Foo { return opt_ok(foo); }`
fn opt_ok(data voidptr, size int) Option {
if size >= 255 {
panic('option size too big: $size (max is 255), this is a temporary limit')
}
res := Option {
ok: true
}
C.memcpy(res.data, data, size)
return res
}
2019-10-23 16:02:39 +02:00
// used internally when returning `none`
fn opt_none() Option {
return Option{ is_none: true }
}
pub fn error(s string) Option {
return Option {
error: s
}
}