mist_parser/parser/common/
statement.rs

1use crate::{
2    Rule,
3    ast::*,
4    ast_ensure, ast_expr,
5    error::{AstError, AstResult, IntoErr, collect_recovered},
6    parser::listen_rule,
7};
8
9impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Block {
10    type Error = AstError<'a, Self>;
11
12    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
13        let mut inner = pair.clone().into_inner();
14
15        ast_ensure!(pair, Rule::block => {
16            ast_expr!(Block(collect_recovered(inner.next().unwrap().into_inner()), inner.next().map(Spanned::try_from).transpose()))
17        })
18    }
19}
20
21impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for StatementBranch {
22    type Error = AstError<'a, Self>;
23
24    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
25        let mut inner = pair.clone().into_inner();
26
27        ast_ensure!(pair, Rule::statement_branch => {
28            ast_expr!(StatementBranch {
29                condition: inner.next().unwrap().try_into(),
30                body: inner.next().unwrap().try_into().map(Box::new),
31            })
32        })
33    }
34}
35
36impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Statement {
37    type Error = AstError<'a, Self>;
38
39    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
40        let rule = pair.as_rule();
41        let mut inner = pair.clone().into_inner();
42
43        match rule {
44            Rule::statement | Rule::basic_stmt | Rule::control_flow => {
45                Statement::try_from(inner.next().unwrap())
46            }
47
48            Rule::block => ast_expr!(Statement::Block(pair.try_into())),
49
50            Rule::var_decl_statement => ast_expr!(Statement::VarDecl(pair.try_into())),
51
52            Rule::return_stmt => {
53                ast_expr!(Statement::Return(
54                    inner.next().map(Expression::try_from).transpose()
55                ))
56            }
57
58            Rule::break_stmt => Ok(Statement::Break),
59
60            Rule::continue_stmt => Ok(Statement::Continue),
61
62            Rule::if_stmt => {
63                ast_expr!(Statement::If {
64                    initial: inner.next().unwrap().try_into(),
65                    else_if: collect_recovered(inner.next().unwrap().into_inner()),
66                    else_branch: inner
67                        .next()
68                        .map(Expression::try_from)
69                        .transpose()
70                        .map(|v| v.map(Box::new))
71                        .get_map(|v| { Some(Box::new(v)) }),
72                })
73            }
74
75            Rule::while_stmt => ast_expr!(Statement::While(inner.next().unwrap().try_into())),
76
77            Rule::loop_stmt => ast_expr!(Statement::Loop(inner.next().unwrap().try_into())),
78
79            Rule::c_for_stmt => ast_expr!(Statement::CStyleFor {
80                init: inner.next().unwrap().try_into(),
81                condition: inner.next().unwrap().try_into(),
82                update: inner.next().unwrap().try_into(),
83                body: inner.next().unwrap().try_into(),
84            }),
85
86            Rule::for_stmt => ast_expr!(Statement::For {
87                mutable: Ok(listen_rule(&mut inner, Rule::mutable)) as AstResult<'_, bool>,
88                pattern: inner.next().unwrap().try_into(),
89                iterator: inner.next().unwrap().try_into(),
90                body: inner.next().unwrap().try_into().map(Box::new),
91            }),
92
93            Rule::match_stmt => ast_expr!(Statement::Match(
94                inner.next().unwrap().try_into(),
95                inner
96                    .map(|match_itms| {
97                        let mut match_inner = match_itms.into_inner();
98                        Ok((
99                            collect_recovered(match_inner.next().unwrap().into_inner()).get()?,
100                            Expression::try_from(match_inner.next().unwrap()).get()?,
101                        ))
102                    })
103                    .collect::<AstResult<'a, Vec<_>>>(),
104            )),
105
106            _ => AstError::bug_unimplemented(pair),
107        }
108    }
109}
mist_parser/parser/common/statement.rs

mist_parser/parser/common/
statement.rs
