1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
use crate::parser::{Expr, ExprT, Metadata, Scope};
#[derive(Clone, Debug)]
pub enum DepthExpr<'a> {
Decision {
cond: Box<DepthExpr<'a>>,
t: Scope,
else_branch: Option<Box<Vec<DepthExpr<'a>>>>,
},
IO(&'a str),
Process(&'a str),
}
pub fn parse<'a, 'b>(vec: &'b Vec<Expr<'a>>) -> Vec<DepthExpr<'a>> {
let mut exprs: Vec<DepthExpr<'a>> = Vec::new();
let mut it = vec
.iter()
.peekable();
while let Some(e) = it.next() {
if let ExprT::Decision((cond, scope)) = e.expr {
let cond = DepthExpr::Process(cond);
for e in it.clone() {
if e.meta == Some(Metadata::EndScope) {
break;
}
}
exprs.push(DepthExpr::Decision {
cond: Box::new(cond),
t: scope,
else_branch: Some(Box::new(parse(&entire_scopes(
it.clone()
.cloned(),
)))),
});
}
}
exprs
}
fn entire_scopes<'a>(it: impl Iterator<Item = Expr<'a>>) -> Vec<Expr<'a>> {
let mut exprs: Vec<Expr<'a>> = Vec::new();
let mut scope_count: u32 = 1; // assume we already entered the scope
for i in it {
if scope_count == 0 {
break;
}
if let Some(meta) = i.meta {
match meta {
Metadata::StartScope => {
scope_count = scope_count
.checked_add(1)
.expect("Scopes nested too deep")
}
Metadata::EndScope => {
scope_count = scope_count
.checked_sub(1)
.expect("Closed not opened scope")
}
}
}
exprs.push(i);
}
exprs
}
|
