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
|
// sprit-forth: A portable subroutine-threaded Forth.
// Copyright (C) 2023 Clyne Sullivan <clyne@bitgloo.com>
//
// This library is free software; you can redistribute it and/or modify it
// under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; either version 2 of the License, or (at your
// option) any later version.
//
// This library is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for
// more details.
//
// You should have received a copy of the GNU Library General Public License
// along with this library; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
#include "core.hpp"
#include "state.hpp"
#include "types.hpp"
#include <cctype>
#include <cstdlib>
[[nodiscard]]
static Error parseword(const char *start, const char *end)
{
auto result = Error::none;
if (start != end) {
if (auto word = find(start, end - start); word) {
if (!word->immediate() && STATE) {
comma((Cell)word->list);
} else {
result = execute1(word);
}
} else if (isdigit(*start)) {
push(std::atoi(start));
if (STATE)
compileliteral();
}
}
return result;
}
[[nodiscard]]
static Error parseSource()
{
auto result = Error::none;
char *start = nullptr;
char *end;
char *s;
while (result == Error::none && haskey()) {
s = (char *)DICT[DIdxSource];
++DICT[DIdxSource];
--DICT[DIdxSrcLen];
if (isspace(*s)) {
if (start) {
result = parseword(start, end + 1);
start = nullptr;
}
} else {
if (!start) {
start = s;
end = start;
} else {
++end;
}
}
}
// Parse the final word if it is non-empty.
if (start)
result = parseword(start, s + 1);
return result;
}
[[nodiscard]]
Error parse()
{
// Reset source buffer and try to fill it with getinput().
DICT[DIdxSource] = (Cell)&DICT[DIdxBegin];
DICT[DIdxSrcLen] = 0;
getinput();
return parseSource();
}
|
