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
|
#!/usr/local/bin/perl -ws
# REMOVE COMMENTS FROM C++ CODE
# ORIGINAL BY Helmut Jarausch
# EXTENDED BY Damian Conway AND Helmut Jarausch
use strict;
use Parse::RecDescent;
use vars qw/ $Grammar /;
my $parser = new Parse::RecDescent $Grammar or die "invalid grammar";
undef $/;
my $text = @ARGV ? <> : <DATA>;
$parser->program($text) or die "malformed C program";
print "Comments\n========\n$parser->{comments}\n";
print "\nCode\n====\n$parser->{code}\n";
print "\nStrings\n=======\n", map(qq{\t"$_"\n}, @{$parser->{strings}});
BEGIN
{ $Grammar=<<'EOF';
program : <skip:''> { @{$thisparser}{qw(comments code strings)} = () }
part(s)
part : comment { $thisparser->{comments} .= $item[1];
$thisparser->{code} .= " "; }
| C_code { $thisparser->{code} .= $item[1]; }
| string { $thisparser->{code} .= qq("$item[1]");
push @{$thisparser->{strings}}, $item[1]; }
C_code : m{(
[^"/]+ # one or more non-delimiters
( # then (optionally)...
/ # a potential comment delimiter
[^*/] # which is not an actual delimiter
)? #
)+ # all repeated once or more
}x
string : m{" # a leading delimiter
(( # zero or more...
\\. # escaped anything
| # or
[^"] # anything but a delimiter
)*
)
"}x
{ $return = $1 }
comment : m{\s* # optional whitespace
// # comment delimiter
[^\n]* # anything except a newline
\n # then a newline
}x
| m{\s* # optional whitespace
/\* # comment opener
(?:[^*]+|\*(?!/))* # anything except */
\*/ # comment closer
([ \t]*)? # trailing blanks or tabs
}x
EOF
}
__DATA__
program test; // for decomment
// using Parse::RecDescent
int main()
{
/* this should
be removed
*/
char *cp1 = "";
char *cp2 = "cp2";
int i; // a counter
// remove this line altogehter
int k;
int more_indented; // keep indentation
int l; /* a loop
variable */
// should be completely removed
char *str = "/* ceci n'est pas un commentaire */";
return 0;
}
|
