1  // Copyright (C) 2019-2025 ADnet Contributors
 2  // This file is part of the ADL library.
 3  
 4  // The ADL 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 ADL 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 ADL library. If not, see <https://www.gnu.org/licenses/>.
16  
17  use crate::{Block, Expression, Indent, Node, NodeID, Statement};
18  use adl_span::Span;
19  
20  use serde::{Deserialize, Serialize};
21  use std::fmt;
22  
23  /// An `if condition block (else next)?` statement.
24  #[derive(Clone, PartialEq, Eq, Serialize, Deserialize, Debug)]
25  pub struct ConditionalStatement {
26      /// The `bool`-typed condition deciding what to evaluate.
27      pub condition: Expression,
28      /// The block to evaluate in case `condition` yields `true`.
29      pub then: Block,
30      /// The statement, if any, to evaluate when `condition` yields `false`.
31      pub otherwise: Option<Box<Statement>>,
32      /// The span from `if` to `next` or to `block`.
33      pub span: Span,
34      /// The ID of the node.
35      pub id: NodeID,
36  }
37  
38  impl fmt::Display for ConditionalStatement {
39      fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
40          writeln!(f, "if {} {{", self.condition)?;
41          for stmt in self.then.statements.iter() {
42              writeln!(f, "{}{}", Indent(stmt), stmt.semicolon())?;
43          }
44          match self.otherwise.as_deref() {
45              None => write!(f, "}}")?,
46              Some(Statement::Block(block)) => {
47                  writeln!(f, "}} else {{")?;
48                  for stmt in block.statements.iter() {
49                      writeln!(f, "{}{}", Indent(stmt), stmt.semicolon())?;
50                  }
51                  write!(f, "}}")?;
52              }
53              Some(Statement::Conditional(cond)) => {
54                  write!(f, "}} else {cond}")?;
55              }
56              Some(_) => panic!("`otherwise` of a `ConditionalStatement` must be a block or conditional."),
57          }
58          Ok(())
59      }
60  }
61  
62  impl From<ConditionalStatement> for Statement {
63      fn from(value: ConditionalStatement) -> Self {
64          Statement::Conditional(value)
65      }
66  }
67  
68  crate::simple_node_impl!(ConditionalStatement);