-
Notifications
You must be signed in to change notification settings - Fork 0
/
mp_cheezparse.pm
345 lines (308 loc) · 10.5 KB
/
mp_cheezparse.pm
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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
#!/usr/bin/env perl
#
# mp_cheezparse.pm
#
# cheesy MP parser
#
package mp_cheezparse;
use strict;
use warnings;
use Data::Dump 'pp';
use MCMUtils;
use Exporter qw(import);
use Data::Dump qw(pp);
our @EXPORT = qw(
tokenize
statementize
parse
parse_rule
compute_cardinality
cardinality
);
our %RULES;
our $scope=3;
##### split the tokens into statement groups (on semicolon) #####
sub statementize {
my @tokens = @_;
my @stmts = ([]);
for my $T (@tokens) {
if ($T->[0] eq 'EOSTMT') {
# Start a new statement token list
push @stmts, [];
}
else {
push @{$stmts[-1]}, $T;
}
}
return @stmts;
}
sub parse {
my @stmts = @_;
for my $rS (@stmts) {
my @S = @$rS;
next unless @S;
#print "\n----------\nParsing: ", pp(\@S), "\n";
if ($rS->[0][0] ne 'SYM') {
print "X: ", pp($rS), "\n";
die "Unexpected!";
}
if ($S[0][1] eq 'ROOT') {
# New root
shift @S;
my $t = parse_rule(@S);
$t->{ROOT}=1;
$RULES{$t->{NAME}} = $t;
}
elsif ($S[1][0] eq 'COLON') {
# New rule
my $t = parse_rule(@S);
$t->{ROOT}=0;
$RULES{$t->{NAME}} = $t;
}
elsif ($S[1][0] eq 'COMMA') {
# New share all?
print "??? SHARE ALL ???\n";
}
else {
print "<<< ", pp($rS), ">>>\n";
die "Eh?";
}
}
return \%RULES;
}
sub create_missing_atoms {
# Check through the rule symbol lists to see if any rules are missing. If so,
# we'll create ATOM references for 'em.
print "\n\nChecking for references to missing rules\n";
my @new_atoms;
for my $rule (sort keys %RULES) {
for my $sym (sort keys %{$RULES{$rule}{SYMS}}) {
if (! exists $RULES{$sym}) {
print "Creating atomic rule '$sym'\n";
push @new_atoms, $sym;
}
}
}
$RULES{$_} = { ATOM=>1, CARD=>1, ROOT=>0, NAME=>$_, SYMS=>{} } for @new_atoms;
}
sub compute_cardinality {
# Compute rule cardinality. It's effectively done as a toposort, as we've already assigned
# atoms (rules with no dependencies) as having cardinality 1. Each pass, we remove
# from each rules SYM list all rules having a cardinality. If the rule has no SYMs left,
# we compute the cardinality, otherwise, we save the rule for next pass.
my $chgs = 1; #force first pass
my $pass = 0;
while ($chgs) {
$chgs = 0;
my @rules_to_check = grep { ! exists $RULES{$_}{CARD} } keys %RULES;
last if !@rules_to_check;
++$pass;
print "\n\n", "*"x80, "\n";
print "Pass $pass: RULES TO CHECK: ", join(", ", @rules_to_check), "\n";
for my $rule (@rules_to_check) {
my @deps = sort keys %{$RULES{$rule}{SYMS}};
if (@deps) {
print "\nRULE $rule: ", scalar(@deps), " dependencies\n";
my @tmp = grep { exists $RULES{$_}{CARD} } keys %RULES;
delete @{$RULES{$rule}{SYMS}}{@tmp};
@deps = sort keys %{$RULES{$rule}{SYMS}};
}
if (@deps) {
print "\tAfter check, ", scalar(@deps), " remain, try again next pass\n";
next;
}
else {
print "\tAll cleared!\n";
}
$RULES{$rule}{CARD} = cardinality($rule);
++$chgs;
}
print "*** $chgs ***\n\n";
}
}
sub display_cardinality_summary {
##### Display the summary
# (the basic cardinality of the system (excluding the share all) is
# the product of the cardinality of the roots)
my $system_cardinality = 1;
for my $rule (sort keys %RULES) {
$system_cardinality *= $RULES{$rule}{CARD} if $RULES{$rule}{ROOT};
next if $RULES{$rule}{ATOM};
printf "%-20.20s %-5.5s %-5.5s % 8u\n", $rule,
($RULES{$rule}{ATOM} ? "ATOM" : ""),
($RULES{$rule}{ROOT} ? "ROOT" : ""),
$RULES{$rule}{CARD};
}
$system_cardinality = eng_not($system_cardinality);
print "System cardinality (excluding share all rules): $system_cardinality\n";
}
sub tokenize {
my $T = shift;
my @tokens = ();
while ($T ne '') {
$T=~/^\s+(.*)/ && do { $T=$1; next };
$T=~/^([A-Za-z][A-Za-z0-9_]*)(.*)/ && do { $T=$2; push @tokens, [ 'SYM', $1 ]; next };
$T=~/^(:)(.*)/ && do { $T=$2; push @tokens, [ 'COLON', $1 ]; next };
$T=~/^(;)(.*)/ && do { $T=$2; push @tokens, [ 'EOSTMT', $1 ]; next };
$T=~/^(,)(.*)/ && do { $T=$2; push @tokens, [ 'COMMA', $1 ]; next };
$T=~/^({)(.*)/ && do { $T=$2; push @tokens, [ 'SET', $1 ]; next };
$T=~/^(})(.*)/ && do { $T=$2; push @tokens, [ 'SETEND', $1 ]; next };
$T=~/^(\(\*)(.*)/ && do { $T=$2; push @tokens, ['RPT', $1 ]; next };
$T=~/^(\*\))(.*)/ && do { $T=$2; push @tokens, ['RPTEND', $1 ]; next };
$T=~/^(<[0-9]+>)(.*)/ && do { $T=$2; push @tokens, ['PROB', $1 ]; next };
$T=~/^(<[0-9]+\.[0-9]*>)(.*)/ && do { $T=$2; push @tokens, ['PROB', $1 ]; next };
$T=~/^(<[0-9]*>\.[0-9]+>)(.*)/ && do { $T=$2; push @tokens, ['PROB', $1 ]; next };
# doesn't work: cheesed it at end
#$T=~m{^(<[-0-9/.,]+>)(.*)} && do { $T=$2; push @tokens, ['PROBS', $1 ]; next };
$T=~/^(\()(.*)/ && do { $T=$2; push @tokens, ['ALTBEG', $1 ]; next };
$T=~/^(\))(.*)/ && do { $T=$2; push @tokens, ['ALTEND', $1 ]; next };
$T=~/^(\|)(.*)/ && do { $T=$2; push @tokens, ['ALT', $1 ]; next };
# Cheese
$T=~m{^(<.+?>)(.*)} && do { $T=$2; push @tokens, ['PROB', $1 ]; next };
print "[ $_->[0], $_->[1] ]\n" for @tokens;
die "Ugh! <" . substr($T,0,25);
}
return @tokens;
}
sub parse_rule {
my ($name, @t) = @_;
my $rv = { NAME=> $name->[1] };
die "Expected COLON after rule name ($name->[1])\n"
unless $t[0][0] eq 'COLON';
shift @t;
cnt(PARSE);
# Essentially, everything is an implicit SEQUENCE, and we just need to maintain a
# stack of contexts to push sequences and events into. Each time we hit an operator
# verify the TOS and do the thing.
# If we get set, rpt, altbeg or alt, we push a context onto the stack. If we get
# to an end (alt, altend, rptend, setend) we pop the context off the stack, and add
# it to the end of the new TOS.
#
my @stack = ([]);
while (scalar @t) {
my $tk = shift @t;
#print "--- tk ($tk->[0]; $tk->[1]), TOS:", pp($stack[-1]), "\n";
if ($tk->[0] eq 'RPT') {
push @stack, [ 'RPT' ];
}
elsif ($tk->[0] eq 'RPTEND') {
print "Mismatched context (RPT context expected)", last if $stack[-1][0] ne 'RPT';
my $tmp = pop @stack;
push @{$stack[-1]}, $tmp;
}
elsif ($tk->[0] eq 'SET') {
push @stack, [ 'SET' ];
}
elsif ($tk->[0] eq 'SETEND') {
print "Mismatched context (SET context expected)", last if $stack[-1][0] ne 'SET';
my $tmp = pop @stack;
push @{$stack[-1]}, $tmp;
}
elsif ($tk->[0] eq 'ALTBEG') {
# push the alt wrapper onto the stack, then the first alternation context
push @stack, [ 'ALT' ], [];
}
elsif ($tk->[0] eq 'ALT') {
# Yes, it's -2 here, as the current TOS is expected to be the seq for the
# current alternation. So finish current alternation, wrap it into the
# alt context, then start context for next alt
print "Mismatched context (ALT context expected)", last if $stack[-2][0] ne 'ALT';
my $tmp = pop @stack;
push @{$stack[-1]}, $tmp;
push @stack, [];
}
elsif ($tk->[0] eq 'ALTEND') {
# End of alternation. Close current alternation, wrap it into the alt.
# Then end the alternation block and wrap it into the upper level.
print "Mismatched context (ALT context expected (END))", last if $stack[-2][0] ne 'ALT';
my $tmp = pop @stack;
push @{$stack[-1]}, $tmp;
$tmp = pop @stack;
push @{$stack[-1]}, $tmp;
}
elsif ($tk->[0] eq 'PROB') {
# We don't care about them for now
}
else {
if ($tk->[0] eq 'SYM') {
# make sure we know what symbols are used, for topo-sort and cardinality
$rv->{SYMS}{$tk->[1]} = 0;
}
push @{$stack[-1]}, $tk;
}
}
if (1 != scalar @stack) {
$rv->{UNG} = [ @stack ];
die "UNG!" . pp($rv);
}
else {
if (0 == scalar(@{$stack[0]})) {
$rv->{ATOM} = 1;
$rv->{CARD} = 1;
delete $rv->{SYMS};
}
else {
$rv->{PROD} = $stack[0];
$rv->{ATOM} = 0;
}
}
if (@t) {
$rv->{REST} = [@t];
cnt(FAULTS);
}
#print "stmt: ", pp($rv), "\n";
return $rv;
}
sub cmp_card {
my $ar = shift;
if ("" eq ref $ar->[0]) {
if ($ar->[0] eq 'ALT') { return cmp_alt($ar); }
if ($ar->[0] eq 'SET') { return cmp_set($ar); }
if ($ar->[0] eq 'RPT') { return cmp_rpt($ar); }
if ($ar->[0] eq 'SYM') { return $RULES{$ar->[1]}{CARD}; }
}
if ("ARRAY" eq ref $ar->[0]) {
my $rv = 1;
$rv *= cmp_card($_) for @$ar;
return $rv;
}
die "WTF?";
}
sub cmp_alt {
my $ar = shift;
# An ALT is simply the cardinality of the sum of the cardinality of its branches
my $rv = 0;
$rv += cmp_card($ar->[$_]) for 1 .. $#$ar;
return $rv;
}
sub cmp_rpt {
my $ar = shift;
# Repeat is a loop, so we repeat the body from 0 to scope
my $rv = 1;
$rv *= cmp_card($ar->[$_]) for 1 .. $#$ar;
my $accum = 1; # for 0 repeats
my $tmp = 1; # start
for (1 .. $scope) {
$tmp *= $rv;
$accum += $tmp;
}
return $accum;
}
sub cmp_set {
my $ar = shift;
# set is like sequence: product of components
my $rv = 1;
$rv *= cmp_card($ar->[$_]) for 1 .. $#$ar;
return $rv;
}
sub cardinality {
my $rule = shift;
return $RULES{$rule}{CARD} if exists $RULES{$rule}{CARD};
return 999999999 if ! exists $RULES{$rule}{PROD};
$RULES{$rule}{CARD} = cmp_card($RULES{$rule}{PROD});
if ($RULES{$rule}{CARD} < 0) {
print "BAD CARDINALITY: ", pp($RULES{$rule}), "\n";
die;
}
return $RULES{$rule}{CARD};
}