Commit | Line | Data |
c46d1069 |
1 | package Filter::Keyword::Parser; |
2 | |
3 | use Package::Stash::PP; |
4 | use B qw(svref_2object); |
5 | use Scalar::Util qw(set_prototype); |
6 | use Moo; |
7 | |
8 | has parser => (is => 'ro', required => 1); |
9 | |
10 | has reader => (is => 'ro', required => 1); |
11 | |
12 | has re_add => (is => 'ro', required => 1); |
13 | |
14 | has target_package => (is => 'ro', required => 1); |
15 | |
16 | has keyword_name => (is => 'ro', required => 1); |
17 | |
18 | has stash => (is => 'lazy'); |
19 | |
20 | sub _build_stash { |
21 | my ($self) = @_; |
22 | Package::Stash::PP->new($self->target_package); |
23 | } |
24 | |
25 | has globref => (is => 'lazy', clearer => 'clear_globref'); |
26 | |
27 | sub _build_globref { |
28 | no strict 'refs'; no warnings 'once'; |
29 | \*{join'::',$_[0]->target_package,$_[0]->keyword_name} |
30 | } |
31 | |
32 | after clear_globref => sub { |
33 | my ($self) = @_; |
34 | $self->stash->remove_symbol('&'.$self->keyword_name); |
35 | $self->globref_refcount(undef); |
36 | }; |
37 | |
38 | has globref_refcount => (is => 'rw'); |
39 | |
40 | sub save_refcount { |
41 | my ($self) = @_; |
42 | $self->globref_refcount(svref_2object($self->globref)->REFCNT); |
43 | } |
44 | |
45 | sub have_match { |
46 | my ($self) = @_; |
47 | return 0 unless defined($self->globref_refcount); |
48 | svref_2object($self->globref)->REFCNT > $self->globref_refcount; |
49 | } |
50 | |
51 | has current_match => (is => 'rw'); |
52 | |
53 | has short_circuit => (is => 'rw'); |
54 | |
55 | has code => (is => 'rw', default => sub { '' }); |
56 | |
57 | sub get_next { |
58 | my ($self) = @_; |
59 | if ($self->short_circuit) { |
60 | $self->short_circuit(0); |
61 | $self->${\$self->re_add}; |
62 | return ('', 0); |
63 | } |
64 | if ($self->have_match) { |
65 | $self->clear_globref; |
66 | return $self->${\$self->parser}; |
67 | } |
68 | return $self->check_match; |
69 | } |
70 | |
71 | sub fetch_more { |
72 | my ($self) = @_; |
73 | my $code = $self->code||''; |
74 | my ($extra_code, $not_eof) = $self->${\$self->reader}; |
75 | $code .= $extra_code; |
76 | $self->code($code); |
77 | return $not_eof; |
78 | } |
79 | |
80 | sub match_source { |
81 | my ($self, $first, $second) = @_; |
82 | $self->fetch_more while $self->code =~ /$first\s+\Z/; |
83 | if (my @match = ($self->code =~ /(.*?${first}\s+${second})(.*)\Z/)) { |
84 | $self->code(pop @match); |
85 | my $found = shift(@match); |
86 | return ($found, \@match); |
87 | } |
88 | return; |
89 | } |
90 | |
91 | sub check_match { |
92 | my ($self) = @_; |
93 | unless ($self->code) { |
94 | $self->fetch_more |
95 | or return ('', 0); |
96 | } |
97 | if ( |
98 | my ($stripped, $matches) |
99 | = $self->match_source( |
100 | $self->keyword_name, qr/(\(|[A-Za-z][A-Za-z_0-9]*|{)/ |
101 | ) |
102 | ) { |
103 | my $sub = sub {}; |
104 | set_prototype(\&$sub, '*;@') unless $matches->[0] eq '('; |
105 | { no warnings 'redefine'; *{$self->globref} = $sub; } |
106 | $self->save_refcount; |
107 | $self->current_match($matches); |
108 | $self->short_circuit(1); |
109 | return ($stripped, 1); |
110 | } |
111 | my $code = $self->code; |
112 | $self->code(''); |
113 | return ($code, 1); |
114 | } |
115 | |
116 | 1; |