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
|
use fmt;
use internal::parser;
use strconv;
use strings;
use os::exec;
export type variable = (str, str);
export type interpreter = struct {
vars: []variable,
};
export type error = !(interperror | exec::error | nomem);
export type interperror = !str;
export fn interpret(it: *interpreter, tree: parser::ast) void = {
match (tree.value) {
case parser::assign =>
assign(it, tree.children)!;
case parser::finvoke =>
match (invoke(it, tree.children)) {
case let e: exec::error =>
fmt::errorln(exec::strerror(e))!;
case void => void;
case let e: interperror =>
fmt::fatal(e);
case nomem =>
fmt::fatal("No memory left");
};
};
};
fn printinvoke(it: *interpreter, nodes: []parser::ast) (void | error) = {
const fname = nodes[0].value as parser::varname;
const arglist = nodes[1].value as parser::arglist;
let args = strings::join(", ", arglist...)!;
defer free(args);
fmt::errorfln("{}: {}", fname, args)!;
};
fn print(args: str...) void = {
for (let arg .. args) {
fmt::println(arg)!;
};
};
fn invoke(it: *interpreter, nodes: []parser::ast) (void | error) = {
const fname = nodes[0].value as parser::varname;
const arglist = nodes[1].value as parser::arglist;
let sarglist: []str = [];
defer strings::freeall(sarglist);
for (let arg .. arglist) {
append(sarglist, replacevars(it, arg))!;
};
switch (fname) {
case "print" =>
print(sarglist...);
case =>
let cmd = exec::cmd(fname, sarglist...)?;
let proc = exec::start(&cmd)?;
let status = exec::wait(&proc)?;
};
};
fn replacevars(it: *interpreter, s: str) str = {
let repls: [](str, str) = [];
defer for (let repl .. repls) {
free(repl.0);
};
for (let var .. it.vars) {
let v = fmt::asprintf("${{{}}}", var.0)!;
append(repls, (v, var.1))!;
};
let sa = strings::multireplace(s, repls...)!;
return sa;
};
fn assign(it: *interpreter, nodes: []parser::ast) (void | error) = {
const varname = nodes[0].value as parser::varname;
const operation = nodes[1].value as parser::operation;
let value = 0;
let stack: []int = [];
for (let i = 0z; i < len(operation.stack); i += 1) {
const arg = operation.stack[i];
match (arg) {
case let i: int =>
append(stack, i)?;
case let o: parser::operator =>
if (len(stack) >= 2) {
let last = len(stack) - 1;
let val = switch (o) {
case parser::operator::ADD =>
yield stack[last] + stack[last-1];
case parser::operator::SUBTRACT =>
yield stack[last] - stack[last-1];
case parser::operator::MULTIPLY =>
yield stack[last] * stack[last-1];
case parser::operator::DIVIDE =>
yield stack[last] / stack[last-1];
};
delete(stack[last-1..]);
append(stack, val)?;
} else {
return "Invalid operation": interperror;
};
};
};
let last = len(stack) - 1;
append(it.vars, (varname, strings::dup(strconv::itos(stack[last]))?))?;
};
|
