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
|
/*
* The compiler code necessary to support the #env extension. Eventually this
* should all get sucked into either the compiler syntax extension plugin
* interface.
*/
import util::common;
import std::_str;
import std::_vec;
import std::option;
import std::generic_os;
export expand_syntax_ext;
// FIXME: Need to thread parser through here to handle errors correctly
fn expand_syntax_ext(parser::parser p,
common::span sp,
vec[@ast::expr] args,
option::t[str] body) -> @ast::expr {
if (_vec::len[@ast::expr](args) != 1u) {
p.err("malformed #env call");
}
// FIXME: if this was more thorough it would manufacture an
// option::t[str] rather than just an maybe-empty string.
auto var = expr_to_str(p, args.(0));
alt (generic_os::getenv(var)) {
case (option::none[str]) {
ret make_new_str(p, sp, "");
}
case (option::some[str](?s)) {
ret make_new_str(p, sp, s);
}
}
}
// FIXME: duplicate code copied from extfmt:
fn expr_to_str(parser::parser p,
@ast::expr expr) -> str {
alt (expr.node) {
case (ast::expr_lit(?l, _)) {
alt (l.node) {
case (ast::lit_str(?s)) {
ret s;
}
}
}
}
p.err("malformed #env call");
fail;
}
fn make_new_lit(parser::parser p, common::span sp, ast::lit_ lit)
-> @ast::expr {
auto sp_lit = @rec(node=lit, span=sp);
auto expr = ast::expr_lit(sp_lit, p.get_ann());
ret @rec(node=expr, span=sp);
}
fn make_new_str(parser::parser p, common::span sp, str s) -> @ast::expr {
auto lit = ast::lit_str(s);
ret make_new_lit(p, sp, lit);
}
//
// Local Variables:
// mode: rust
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// compile-command: "make -k -C $RBUILD 2>&1 | sed -e 's/\\/x\\//x:\\//g'";
// End:
//
|
