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
|
use super::ast;
use super::runtime::{advance_v, Term, Value};
use std::fmt;
use std::rc::Rc;
#[derive(Debug, Clone, PartialEq)]
pub struct Builtin {
pub identifier: &'static str,
pub repr_name: &'static str,
pub arguments: Vec<Value>,
}
impl fmt::Display for Builtin {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let mut arg_str = String::new();
for argument in &self.arguments {
arg_str.push_str(format!(" {}", argument).as_str());
}
write!(f, "Builtin({}){}", self.repr_name, arg_str)
}
}
pub const B_INTEGER_EQ0: &str = "int.eq0?";
pub const B_INTEGER_INCREMENT: &str = "int.increment";
pub const B_INTEGER_ADD: &str = "int.add";
pub const B_INTEGER_ADD_1: &str = "##int.add_1";
pub fn make_boolean_true_function() -> Term {
let x = advance_v();
let y = advance_v();
Term::Abstraction(x, Rc::new(Term::Abstraction(y, Rc::new(Term::Variable(x)))))
}
pub fn make_boolean_false_function() -> Term {
let x = advance_v();
let y = advance_v();
Term::Abstraction(x, Rc::new(Term::Abstraction(y, Rc::new(Term::Variable(y)))))
}
pub fn make_identity_function() -> Term {
let v = advance_v();
Term::Abstraction(v, Rc::new(Term::Variable(v)))
}
pub fn try_ast_symbol_to_builtin_term(symbol: &ast::Symbol) -> Option<Term> {
let builtin = match symbol.as_str() {
"true" => return Some(make_boolean_true_function()),
"false" => return Some(make_boolean_false_function()),
"id" => return Some(make_identity_function()),
B_INTEGER_EQ0 => Builtin {
identifier: B_INTEGER_EQ0,
repr_name: B_INTEGER_EQ0,
arguments: vec![],
},
B_INTEGER_INCREMENT => Builtin {
identifier: B_INTEGER_INCREMENT,
repr_name: B_INTEGER_INCREMENT,
arguments: vec![],
},
B_INTEGER_ADD => Builtin {
identifier: B_INTEGER_ADD,
repr_name: B_INTEGER_ADD,
arguments: vec![],
},
_ => return None,
};
Some(Term::Builtin(builtin))
}
pub fn evaluate_builtin(builtin: &Builtin, rhs: Rc<Term>) -> Result<(Rc<Term>, usize), String> {
let result_term = match builtin.identifier {
B_INTEGER_EQ0 => match &*rhs {
Term::Primitive(primitive) => match primitive {
Value::Integer(value) => {
if *value == 0 {
make_boolean_true_function()
} else {
make_boolean_false_function()
}
}
other => {
return Err(format!(
"[runtime] cannot apply builtin {} to argument {}",
builtin.identifier, other
))
}
},
_ => return Ok((Rc::new(Term::Builtin(builtin.clone())), 0)),
},
B_INTEGER_INCREMENT => match &*rhs {
Term::Primitive(primitive) => match primitive {
Value::Integer(value) => Term::Primitive(Value::Integer(value + 1)),
other => {
return Err(format!(
"[runtime] cannot apply builtin {} to argument {}",
builtin.identifier, other
))
}
},
_ => return Ok((Rc::new(Term::Builtin(builtin.clone())), 0)),
},
B_INTEGER_ADD => match &*rhs {
Term::Primitive(primitive) => match primitive {
Value::Integer(_) => {
let new_builtin = Builtin {
identifier: B_INTEGER_ADD_1,
repr_name: builtin.identifier,
arguments: vec![primitive.clone()],
};
Term::Builtin(new_builtin)
}
other => {
return Err(format!(
"[runtime] cannot apply builtin {} to argument {}",
builtin.identifier, other
))
}
},
_ => return Ok((Rc::new(Term::Builtin(builtin.clone())), 0)),
},
B_INTEGER_ADD_1 => match &*rhs {
Term::Primitive(primitive) => match primitive {
Value::Integer(value) => {
assert_eq!(builtin.arguments.len(), 1);
let summand = &builtin.arguments[0];
match summand {
Value::Integer(summand_value) => {
Term::Primitive(Value::Integer(summand_value + value))
}
other => {
return Err(format!(
"[runtime] cannot apply builtin {} to argument {}",
builtin.identifier, other
))
}
}
}
other => {
return Err(format!(
"[runtime] cannot apply builtin {} to argument {}",
builtin.identifier, other
))
}
},
_ => return Ok((Rc::new(Term::Builtin(builtin.clone())), 0)),
},
_ => {
return Err(format!(
"[runtime] invalid builtin evaluated: {}",
builtin.identifier
))
}
};
Ok((Rc::new(result_term), 1))
}
|
