leo_ast/functions/variant.rs
1// Copyright (C) 2019-2025 Provable Inc.
2// This file is part of the Leo library.
3
4// The Leo library is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8
9// The Leo library is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13
14// You should have received a copy of the GNU General Public License
15// along with the Leo library. If not, see <https://www.gnu.org/licenses/>.
16
17use serde::{Deserialize, Serialize};
18
19use std::fmt;
20
21/// Functions are always one of six variants.
22/// A transition function is permitted the ability to manipulate records.
23/// An asynchronous transition function is a transition function that calls an asynchronous function.
24/// A regular function is not permitted to manipulate records.
25/// An asynchronous function contains on-chain operations.
26/// An inline function is directly copied at the call site.
27#[derive(Copy, Clone, Debug, Default, Serialize, Deserialize, PartialEq, Eq)]
28pub enum Variant {
29 #[default]
30 Inline,
31 Function,
32 Transition,
33 AsyncTransition,
34 AsyncFunction,
35 /// `script` can only appear in test files, and is used for
36 /// tests which are interpreted rather than run on snarkvm using a Ledger and VM.
37 Script,
38}
39
40impl Variant {
41 /// Returns true if the variant is async.
42 pub fn is_async(self) -> bool {
43 matches!(self, Variant::AsyncFunction | Variant::AsyncTransition)
44 }
45
46 /// Returns true if the variant is a transition.
47 pub fn is_transition(self) -> bool {
48 matches!(self, Variant::Transition | Variant::AsyncTransition)
49 }
50
51 /// Returns true if the variant is a function.
52 pub fn is_function(self) -> bool {
53 matches!(self, Variant::AsyncFunction | Variant::Function)
54 }
55
56 /// Is this a `script`?
57 pub fn is_script(self) -> bool {
58 matches!(self, Variant::Script)
59 }
60
61 /// Returns true if the variant is an async function.
62 pub fn is_async_function(self) -> bool {
63 matches!(self, Variant::AsyncFunction)
64 }
65}
66
67impl fmt::Display for Variant {
68 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
69 match self {
70 Self::Inline => write!(f, "inline"),
71 Self::Function => write!(f, "function"),
72 Self::Transition => write!(f, "transition"),
73 Self::AsyncTransition => write!(f, "async transition"),
74 Self::AsyncFunction => write!(f, "async function"),
75 Self::Script => write!(f, "script"),
76 }
77 }
78}