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
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
#![allow(dead_code)]
use erg_common::set::Set;
use erg_common::traits::{Locational, Stream};
use erg_common::Str;
use erg_common::{enum_unwrap, set};
use crate::ast::{
Accessor, Args, Block, Call, Def, DefBody, Expr, Lambda, LambdaSignature, Module, ParamPattern,
ParamSignature, Params, PosArg, Signature, SubrSignature, TypeBoundSpecs, VarName, VarPattern,
};
use crate::token::{Token, TokenKind};
#[derive(Debug)]
pub struct Desugarer {
desugared: Set<Str>,
}
impl Desugarer {
pub fn new() -> Desugarer {
Self {
desugared: Set::default(),
}
}
pub fn desugar(&mut self, module: Module) -> Module {
self.desugar_multiple_pattern_def(module)
}
fn desugar_ubar_lambda(&self, _module: Module) -> Module {
todo!()
}
fn desugar_multiple_pattern_def(&self, mut module: Module) -> Module {
let mut new = Module::with_capacity(module.len());
while let Some(chunk) = module.lpop() {
match chunk {
Expr::Def(def) if def.is_subr() => {
if let Some(Expr::Def(previous)) = new.last() {
if previous.is_subr() && previous.sig.name_as_str() == def.sig.name_as_str()
{
let mut previous = enum_unwrap!(new.pop().unwrap(), Expr::Def);
let name = def.sig.ident().unwrap().clone();
let op = Token::from_str(TokenKind::FuncArrow, "->");
let (call, return_t_spec) = if previous.body.block.len() == 1
&& previous.body.block.first().unwrap().is_match_call()
{
let mut call =
enum_unwrap!(previous.body.block.remove(0), Expr::Call);
let sig = enum_unwrap!(def.sig, Signature::Subr);
let return_t_spec = sig.return_t_spec;
let first_arg = sig.params.non_defaults.first().unwrap();
if let Some(name) = first_arg.inspect() {
call.args.remove_pos(0);
let arg = PosArg::new(Expr::local(
name,
first_arg.ln_begin().unwrap(),
first_arg.col_begin().unwrap(),
));
call.args.insert_pos(0, arg);
}
let sig = LambdaSignature::new(
sig.params,
return_t_spec.clone(),
sig.bounds,
);
let new_branch = Lambda::new(sig, op, def.body.block, def.body.id);
call.args.push_pos(PosArg::new(Expr::Lambda(new_branch)));
(call, return_t_spec)
} else {
let sig = enum_unwrap!(previous.sig, Signature::Subr);
let match_symbol = Expr::static_local("match");
let sig =
LambdaSignature::new(sig.params, sig.return_t_spec, sig.bounds);
let first_branch = Lambda::new(
sig,
op.clone(),
previous.body.block,
previous.body.id,
);
let sig = enum_unwrap!(def.sig, Signature::Subr);
let return_t_spec = sig.return_t_spec;
let sig = LambdaSignature::new(
sig.params,
return_t_spec.clone(),
sig.bounds,
);
let second_branch =
Lambda::new(sig, op, def.body.block, def.body.id);
let args = Args::new(
vec![
PosArg::new(Expr::dummy_local("_")), PosArg::new(Expr::Lambda(first_branch)),
PosArg::new(Expr::Lambda(second_branch)),
],
vec![],
None,
);
let call = Call::new(match_symbol, None, args);
(call, return_t_spec)
};
let param_name = enum_unwrap!(&call.args.pos_args().iter().next().unwrap().expr, Expr::Accessor:(Accessor::Local:(_))).inspect();
let param = VarName::new(Token::new(
TokenKind::Symbol,
param_name,
name.ln_begin().unwrap(),
name.col_end().unwrap() + 1, ));
let param =
ParamSignature::new(ParamPattern::VarName(param), None, None);
let params = Params::new(vec![param], vec![], None);
let sig = Signature::Subr(SubrSignature::new(
set! {},
name,
params,
return_t_spec,
TypeBoundSpecs::empty(),
));
let body = DefBody::new(
def.body.op,
Block::new(vec![Expr::Call(call)]),
def.body.id,
);
let def = Def::new(sig, body);
new.push(Expr::Def(def));
} else {
new.push(Expr::Def(def));
}
} else {
new.push(Expr::Def(def));
}
}
other => {
new.push(other);
}
}
}
new
}
fn desugar_literal_pattern(&self, _mod: Module) -> Module {
todo!()
}
fn desugar_nest_vars_pattern(&self, mut module: Module) -> Module {
let mut new = Module::with_capacity(module.len());
while let Some(chunk) = module.lpop() {
match chunk {
Expr::Def(def) => {
if let Signature::Var(v) = &def.sig {
match &v.pat {
VarPattern::Array(_a) => {}
VarPattern::Record(_r) => {}
_ => {}
}
}
new.push(Expr::Def(def));
}
other => {
new.push(other);
}
}
}
new
}
fn desugar_record_pattern(&self, _mod: Module) -> Module {
todo!()
}
fn desugar_refinement_pattern(&self, _mod: Module) -> Module {
todo!()
}
fn desugar_trait_parameter(&self, _mod: Module) -> Module {
todo!()
}
}
impl Default for Desugarer {
fn default() -> Self {
Self::new()
}
}
