| 1 | ############################################################################# |
| 2 | # Pod/Select.pm -- function to select portions of POD docs |
| 3 | # |
| 4 | # Copyright (C) 1996-2000 by Bradford Appleton. All rights reserved. |
| 5 | # This file is part of "PodParser". PodParser is free software; |
| 6 | # you can redistribute it and/or modify it under the same terms |
| 7 | # as Perl itself. |
| 8 | ############################################################################# |
| 9 | |
| 10 | package Pod::Select; |
| 11 | |
| 12 | use vars qw($VERSION); |
| 13 | $VERSION = 1.30; ## Current version of this package |
| 14 | require 5.005; ## requires this Perl version or later |
| 15 | |
| 16 | ############################################################################# |
| 17 | |
| 18 | =head1 NAME |
| 19 | |
| 20 | Pod::Select, podselect() - extract selected sections of POD from input |
| 21 | |
| 22 | =head1 SYNOPSIS |
| 23 | |
| 24 | use Pod::Select; |
| 25 | |
| 26 | ## Select all the POD sections for each file in @filelist |
| 27 | ## and print the result on standard output. |
| 28 | podselect(@filelist); |
| 29 | |
| 30 | ## Same as above, but write to tmp.out |
| 31 | podselect({-output => "tmp.out"}, @filelist): |
| 32 | |
| 33 | ## Select from the given filelist, only those POD sections that are |
| 34 | ## within a 1st level section named any of: NAME, SYNOPSIS, OPTIONS. |
| 35 | podselect({-sections => ["NAME|SYNOPSIS", "OPTIONS"]}, @filelist): |
| 36 | |
| 37 | ## Select the "DESCRIPTION" section of the PODs from STDIN and write |
| 38 | ## the result to STDERR. |
| 39 | podselect({-output => ">&STDERR", -sections => ["DESCRIPTION"]}, \*STDIN); |
| 40 | |
| 41 | or |
| 42 | |
| 43 | use Pod::Select; |
| 44 | |
| 45 | ## Create a parser object for selecting POD sections from the input |
| 46 | $parser = new Pod::Select(); |
| 47 | |
| 48 | ## Select all the POD sections for each file in @filelist |
| 49 | ## and print the result to tmp.out. |
| 50 | $parser->parse_from_file("<&STDIN", "tmp.out"); |
| 51 | |
| 52 | ## Select from the given filelist, only those POD sections that are |
| 53 | ## within a 1st level section named any of: NAME, SYNOPSIS, OPTIONS. |
| 54 | $parser->select("NAME|SYNOPSIS", "OPTIONS"); |
| 55 | for (@filelist) { $parser->parse_from_file($_); } |
| 56 | |
| 57 | ## Select the "DESCRIPTION" and "SEE ALSO" sections of the PODs from |
| 58 | ## STDIN and write the result to STDERR. |
| 59 | $parser->select("DESCRIPTION"); |
| 60 | $parser->add_selection("SEE ALSO"); |
| 61 | $parser->parse_from_filehandle(\*STDIN, \*STDERR); |
| 62 | |
| 63 | =head1 REQUIRES |
| 64 | |
| 65 | perl5.005, Pod::Parser, Exporter, Carp |
| 66 | |
| 67 | =head1 EXPORTS |
| 68 | |
| 69 | podselect() |
| 70 | |
| 71 | =head1 DESCRIPTION |
| 72 | |
| 73 | B<podselect()> is a function which will extract specified sections of |
| 74 | pod documentation from an input stream. This ability is provided by the |
| 75 | B<Pod::Select> module which is a subclass of B<Pod::Parser>. |
| 76 | B<Pod::Select> provides a method named B<select()> to specify the set of |
| 77 | POD sections to select for processing/printing. B<podselect()> merely |
| 78 | creates a B<Pod::Select> object and then invokes the B<podselect()> |
| 79 | followed by B<parse_from_file()>. |
| 80 | |
| 81 | =head1 SECTION SPECIFICATIONS |
| 82 | |
| 83 | B<podselect()> and B<Pod::Select::select()> may be given one or more |
| 84 | "section specifications" to restrict the text processed to only the |
| 85 | desired set of sections and their corresponding subsections. A section |
| 86 | specification is a string containing one or more Perl-style regular |
| 87 | expressions separated by forward slashes ("/"). If you need to use a |
| 88 | forward slash literally within a section title you can escape it with a |
| 89 | backslash ("\/"). |
| 90 | |
| 91 | The formal syntax of a section specification is: |
| 92 | |
| 93 | =over 4 |
| 94 | |
| 95 | =item * |
| 96 | |
| 97 | I<head1-title-regex>/I<head2-title-regex>/... |
| 98 | |
| 99 | =back |
| 100 | |
| 101 | Any omitted or empty regular expressions will default to ".*". |
| 102 | Please note that each regular expression given is implicitly |
| 103 | anchored by adding "^" and "$" to the beginning and end. Also, if a |
| 104 | given regular expression starts with a "!" character, then the |
| 105 | expression is I<negated> (so C<!foo> would match anything I<except> |
| 106 | C<foo>). |
| 107 | |
| 108 | Some example section specifications follow. |
| 109 | |
| 110 | =over 4 |
| 111 | |
| 112 | =item * |
| 113 | |
| 114 | Match the C<NAME> and C<SYNOPSIS> sections and all of their subsections: |
| 115 | |
| 116 | C<NAME|SYNOPSIS> |
| 117 | |
| 118 | =item * |
| 119 | |
| 120 | Match only the C<Question> and C<Answer> subsections of the C<DESCRIPTION> |
| 121 | section: |
| 122 | |
| 123 | C<DESCRIPTION/Question|Answer> |
| 124 | |
| 125 | =item * |
| 126 | |
| 127 | Match the C<Comments> subsection of I<all> sections: |
| 128 | |
| 129 | C</Comments> |
| 130 | |
| 131 | =item * |
| 132 | |
| 133 | Match all subsections of C<DESCRIPTION> I<except> for C<Comments>: |
| 134 | |
| 135 | C<DESCRIPTION/!Comments> |
| 136 | |
| 137 | =item * |
| 138 | |
| 139 | Match the C<DESCRIPTION> section but do I<not> match any of its subsections: |
| 140 | |
| 141 | C<DESCRIPTION/!.+> |
| 142 | |
| 143 | =item * |
| 144 | |
| 145 | Match all top level sections but none of their subsections: |
| 146 | |
| 147 | C</!.+> |
| 148 | |
| 149 | =back |
| 150 | |
| 151 | =begin _NOT_IMPLEMENTED_ |
| 152 | |
| 153 | =head1 RANGE SPECIFICATIONS |
| 154 | |
| 155 | B<podselect()> and B<Pod::Select::select()> may be given one or more |
| 156 | "range specifications" to restrict the text processed to only the |
| 157 | desired ranges of paragraphs in the desired set of sections. A range |
| 158 | specification is a string containing a single Perl-style regular |
| 159 | expression (a regex), or else two Perl-style regular expressions |
| 160 | (regexs) separated by a ".." (Perl's "range" operator is ".."). |
| 161 | The regexs in a range specification are delimited by forward slashes |
| 162 | ("/"). If you need to use a forward slash literally within a regex you |
| 163 | can escape it with a backslash ("\/"). |
| 164 | |
| 165 | The formal syntax of a range specification is: |
| 166 | |
| 167 | =over 4 |
| 168 | |
| 169 | =item * |
| 170 | |
| 171 | /I<start-range-regex>/[../I<end-range-regex>/] |
| 172 | |
| 173 | =back |
| 174 | |
| 175 | Where each the item inside square brackets (the ".." followed by the |
| 176 | end-range-regex) is optional. Each "range-regex" is of the form: |
| 177 | |
| 178 | =cmd-expr text-expr |
| 179 | |
| 180 | Where I<cmd-expr> is intended to match the name of one or more POD |
| 181 | commands, and I<text-expr> is intended to match the paragraph text for |
| 182 | the command. If a range-regex is supposed to match a POD command, then |
| 183 | the first character of the regex (the one after the initial '/') |
| 184 | absolutely I<must> be a single '=' character; it may not be anything |
| 185 | else (not even a regex meta-character) if it is supposed to match |
| 186 | against the name of a POD command. |
| 187 | |
| 188 | If no I<=cmd-expr> is given then the text-expr will be matched against |
| 189 | plain textblocks unless it is preceded by a space, in which case it is |
| 190 | matched against verbatim text-blocks. If no I<text-expr> is given then |
| 191 | only the command-portion of the paragraph is matched against. |
| 192 | |
| 193 | Note that these two expressions are each implicitly anchored. This |
| 194 | means that when matching against the command-name, there will be an |
| 195 | implicit '^' and '$' around the given I<=cmd-expr>; and when matching |
| 196 | against the paragraph text there will be an implicit '\A' and '\Z' |
| 197 | around the given I<text-expr>. |
| 198 | |
| 199 | Unlike with section-specs, the '!' character does I<not> have any special |
| 200 | meaning (negation or otherwise) at the beginning of a range-spec! |
| 201 | |
| 202 | Some example range specifications follow. |
| 203 | |
| 204 | =over 4 |
| 205 | |
| 206 | =item |
| 207 | Match all C<=for html> paragraphs: |
| 208 | |
| 209 | C</=for html/> |
| 210 | |
| 211 | =item |
| 212 | Match all paragraphs between C<=begin html> and C<=end html> |
| 213 | (note that this will I<not> work correctly if such sections |
| 214 | are nested): |
| 215 | |
| 216 | C</=begin html/../=end html/> |
| 217 | |
| 218 | =item |
| 219 | Match all paragraphs between the given C<=item> name until the end of the |
| 220 | current section: |
| 221 | |
| 222 | C</=item mine/../=head\d/> |
| 223 | |
| 224 | =item |
| 225 | Match all paragraphs between the given C<=item> until the next item, or |
| 226 | until the end of the itemized list (note that this will I<not> work as |
| 227 | desired if the item contains an itemized list nested within it): |
| 228 | |
| 229 | C</=item mine/../=(item|back)/> |
| 230 | |
| 231 | =back |
| 232 | |
| 233 | =end _NOT_IMPLEMENTED_ |
| 234 | |
| 235 | =cut |
| 236 | |
| 237 | ############################################################################# |
| 238 | |
| 239 | use strict; |
| 240 | #use diagnostics; |
| 241 | use Carp; |
| 242 | use Pod::Parser 1.04; |
| 243 | use vars qw(@ISA @EXPORT $MAX_HEADING_LEVEL); |
| 244 | |
| 245 | @ISA = qw(Pod::Parser); |
| 246 | @EXPORT = qw(&podselect); |
| 247 | |
| 248 | ## Maximum number of heading levels supported for '=headN' directives |
| 249 | *MAX_HEADING_LEVEL = \3; |
| 250 | |
| 251 | ############################################################################# |
| 252 | |
| 253 | =head1 OBJECT METHODS |
| 254 | |
| 255 | The following methods are provided in this module. Each one takes a |
| 256 | reference to the object itself as an implicit first parameter. |
| 257 | |
| 258 | =cut |
| 259 | |
| 260 | ##--------------------------------------------------------------------------- |
| 261 | |
| 262 | ## =begin _PRIVATE_ |
| 263 | ## |
| 264 | ## =head1 B<_init_headings()> |
| 265 | ## |
| 266 | ## Initialize the current set of active section headings. |
| 267 | ## |
| 268 | ## =cut |
| 269 | ## |
| 270 | ## =end _PRIVATE_ |
| 271 | |
| 272 | use vars qw(%myData @section_headings); |
| 273 | |
| 274 | sub _init_headings { |
| 275 | my $self = shift; |
| 276 | local *myData = $self; |
| 277 | |
| 278 | ## Initialize current section heading titles if necessary |
| 279 | unless (defined $myData{_SECTION_HEADINGS}) { |
| 280 | local *section_headings = $myData{_SECTION_HEADINGS} = []; |
| 281 | for (my $i = 0; $i < $MAX_HEADING_LEVEL; ++$i) { |
| 282 | $section_headings[$i] = ''; |
| 283 | } |
| 284 | } |
| 285 | } |
| 286 | |
| 287 | ##--------------------------------------------------------------------------- |
| 288 | |
| 289 | =head1 B<curr_headings()> |
| 290 | |
| 291 | ($head1, $head2, $head3, ...) = $parser->curr_headings(); |
| 292 | $head1 = $parser->curr_headings(1); |
| 293 | |
| 294 | This method returns a list of the currently active section headings and |
| 295 | subheadings in the document being parsed. The list of headings returned |
| 296 | corresponds to the most recently parsed paragraph of the input. |
| 297 | |
| 298 | If an argument is given, it must correspond to the desired section |
| 299 | heading number, in which case only the specified section heading is |
| 300 | returned. If there is no current section heading at the specified |
| 301 | level, then C<undef> is returned. |
| 302 | |
| 303 | =cut |
| 304 | |
| 305 | sub curr_headings { |
| 306 | my $self = shift; |
| 307 | $self->_init_headings() unless (defined $self->{_SECTION_HEADINGS}); |
| 308 | my @headings = @{ $self->{_SECTION_HEADINGS} }; |
| 309 | return (@_ > 0 and $_[0] =~ /^\d+$/) ? $headings[$_[0] - 1] : @headings; |
| 310 | } |
| 311 | |
| 312 | ##--------------------------------------------------------------------------- |
| 313 | |
| 314 | =head1 B<select()> |
| 315 | |
| 316 | $parser->select($section_spec1,$section_spec2,...); |
| 317 | |
| 318 | This method is used to select the particular sections and subsections of |
| 319 | POD documentation that are to be printed and/or processed. The existing |
| 320 | set of selected sections is I<replaced> with the given set of sections. |
| 321 | See B<add_selection()> for adding to the current set of selected |
| 322 | sections. |
| 323 | |
| 324 | Each of the C<$section_spec> arguments should be a section specification |
| 325 | as described in L<"SECTION SPECIFICATIONS">. The section specifications |
| 326 | are parsed by this method and the resulting regular expressions are |
| 327 | stored in the invoking object. |
| 328 | |
| 329 | If no C<$section_spec> arguments are given, then the existing set of |
| 330 | selected sections is cleared out (which means C<all> sections will be |
| 331 | processed). |
| 332 | |
| 333 | This method should I<not> normally be overridden by subclasses. |
| 334 | |
| 335 | =cut |
| 336 | |
| 337 | use vars qw(@selected_sections); |
| 338 | |
| 339 | sub select { |
| 340 | my $self = shift; |
| 341 | my @sections = @_; |
| 342 | local *myData = $self; |
| 343 | local $_; |
| 344 | |
| 345 | ### NEED TO DISCERN A SECTION-SPEC FROM A RANGE-SPEC (look for m{^/.+/$}?) |
| 346 | |
| 347 | ##--------------------------------------------------------------------- |
| 348 | ## The following is a blatant hack for backward compatibility, and for |
| 349 | ## implementing add_selection(). If the *first* *argument* is the |
| 350 | ## string "+", then the remaining section specifications are *added* |
| 351 | ## to the current set of selections; otherwise the given section |
| 352 | ## specifications will *replace* the current set of selections. |
| 353 | ## |
| 354 | ## This should probably be fixed someday, but for the present time, |
| 355 | ## it seems incredibly unlikely that "+" would ever correspond to |
| 356 | ## a legitimate section heading |
| 357 | ##--------------------------------------------------------------------- |
| 358 | my $add = ($sections[0] eq "+") ? shift(@sections) : ""; |
| 359 | |
| 360 | ## Reset the set of sections to use |
| 361 | unless (@sections > 0) { |
| 362 | delete $myData{_SELECTED_SECTIONS} unless ($add); |
| 363 | return; |
| 364 | } |
| 365 | $myData{_SELECTED_SECTIONS} = [] |
| 366 | unless ($add && exists $myData{_SELECTED_SECTIONS}); |
| 367 | local *selected_sections = $myData{_SELECTED_SECTIONS}; |
| 368 | |
| 369 | ## Compile each spec |
| 370 | my $spec; |
| 371 | for $spec (@sections) { |
| 372 | if ( defined($_ = &_compile_section_spec($spec)) ) { |
| 373 | ## Store them in our sections array |
| 374 | push(@selected_sections, $_); |
| 375 | } |
| 376 | else { |
| 377 | carp "Ignoring section spec \"$spec\"!\n"; |
| 378 | } |
| 379 | } |
| 380 | } |
| 381 | |
| 382 | ##--------------------------------------------------------------------------- |
| 383 | |
| 384 | =head1 B<add_selection()> |
| 385 | |
| 386 | $parser->add_selection($section_spec1,$section_spec2,...); |
| 387 | |
| 388 | This method is used to add to the currently selected sections and |
| 389 | subsections of POD documentation that are to be printed and/or |
| 390 | processed. See <select()> for replacing the currently selected sections. |
| 391 | |
| 392 | Each of the C<$section_spec> arguments should be a section specification |
| 393 | as described in L<"SECTION SPECIFICATIONS">. The section specifications |
| 394 | are parsed by this method and the resulting regular expressions are |
| 395 | stored in the invoking object. |
| 396 | |
| 397 | This method should I<not> normally be overridden by subclasses. |
| 398 | |
| 399 | =cut |
| 400 | |
| 401 | sub add_selection { |
| 402 | my $self = shift; |
| 403 | $self->select("+", @_); |
| 404 | } |
| 405 | |
| 406 | ##--------------------------------------------------------------------------- |
| 407 | |
| 408 | =head1 B<clear_selections()> |
| 409 | |
| 410 | $parser->clear_selections(); |
| 411 | |
| 412 | This method takes no arguments, it has the exact same effect as invoking |
| 413 | <select()> with no arguments. |
| 414 | |
| 415 | =cut |
| 416 | |
| 417 | sub clear_selections { |
| 418 | my $self = shift; |
| 419 | $self->select(); |
| 420 | } |
| 421 | |
| 422 | ##--------------------------------------------------------------------------- |
| 423 | |
| 424 | =head1 B<match_section()> |
| 425 | |
| 426 | $boolean = $parser->match_section($heading1,$heading2,...); |
| 427 | |
| 428 | Returns a value of true if the given section and subsection heading |
| 429 | titles match any of the currently selected section specifications in |
| 430 | effect from prior calls to B<select()> and B<add_selection()> (or if |
| 431 | there are no explictly selected/deselected sections). |
| 432 | |
| 433 | The arguments C<$heading1>, C<$heading2>, etc. are the heading titles of |
| 434 | the corresponding sections, subsections, etc. to try and match. If |
| 435 | C<$headingN> is omitted then it defaults to the current corresponding |
| 436 | section heading title in the input. |
| 437 | |
| 438 | This method should I<not> normally be overridden by subclasses. |
| 439 | |
| 440 | =cut |
| 441 | |
| 442 | sub match_section { |
| 443 | my $self = shift; |
| 444 | my (@headings) = @_; |
| 445 | local *myData = $self; |
| 446 | |
| 447 | ## Return true if no restrictions were explicitly specified |
| 448 | my $selections = (exists $myData{_SELECTED_SECTIONS}) |
| 449 | ? $myData{_SELECTED_SECTIONS} : undef; |
| 450 | return 1 unless ((defined $selections) && (@{$selections} > 0)); |
| 451 | |
| 452 | ## Default any unspecified sections to the current one |
| 453 | my @current_headings = $self->curr_headings(); |
| 454 | for (my $i = 0; $i < $MAX_HEADING_LEVEL; ++$i) { |
| 455 | (defined $headings[$i]) or $headings[$i] = $current_headings[$i]; |
| 456 | } |
| 457 | |
| 458 | ## Look for a match against the specified section expressions |
| 459 | my ($section_spec, $regex, $negated, $match); |
| 460 | for $section_spec ( @{$selections} ) { |
| 461 | ##------------------------------------------------------ |
| 462 | ## Each portion of this spec must match in order for |
| 463 | ## the spec to be matched. So we will start with a |
| 464 | ## match-value of 'true' and logically 'and' it with |
| 465 | ## the results of matching a given element of the spec. |
| 466 | ##------------------------------------------------------ |
| 467 | $match = 1; |
| 468 | for (my $i = 0; $i < $MAX_HEADING_LEVEL; ++$i) { |
| 469 | $regex = $section_spec->[$i]; |
| 470 | $negated = ($regex =~ s/^\!//); |
| 471 | $match &= ($negated ? ($headings[$i] !~ /${regex}/) |
| 472 | : ($headings[$i] =~ /${regex}/)); |
| 473 | last unless ($match); |
| 474 | } |
| 475 | return 1 if ($match); |
| 476 | } |
| 477 | return 0; ## no match |
| 478 | } |
| 479 | |
| 480 | ##--------------------------------------------------------------------------- |
| 481 | |
| 482 | =head1 B<is_selected()> |
| 483 | |
| 484 | $boolean = $parser->is_selected($paragraph); |
| 485 | |
| 486 | This method is used to determine if the block of text given in |
| 487 | C<$paragraph> falls within the currently selected set of POD sections |
| 488 | and subsections to be printed or processed. This method is also |
| 489 | responsible for keeping track of the current input section and |
| 490 | subsections. It is assumed that C<$paragraph> is the most recently read |
| 491 | (but not yet processed) input paragraph. |
| 492 | |
| 493 | The value returned will be true if the C<$paragraph> and the rest of the |
| 494 | text in the same section as C<$paragraph> should be selected (included) |
| 495 | for processing; otherwise a false value is returned. |
| 496 | |
| 497 | =cut |
| 498 | |
| 499 | sub is_selected { |
| 500 | my ($self, $paragraph) = @_; |
| 501 | local $_; |
| 502 | local *myData = $self; |
| 503 | |
| 504 | $self->_init_headings() unless (defined $myData{_SECTION_HEADINGS}); |
| 505 | |
| 506 | ## Keep track of current sections levels and headings |
| 507 | $_ = $paragraph; |
| 508 | if (/^=((?:sub)*)(?:head(?:ing)?|sec(?:tion)?)(\d*)\s+(.*)\s*$/) |
| 509 | { |
| 510 | ## This is a section heading command |
| 511 | my ($level, $heading) = ($2, $3); |
| 512 | $level = 1 + (length($1) / 3) if ((! length $level) || (length $1)); |
| 513 | ## Reset the current section heading at this level |
| 514 | $myData{_SECTION_HEADINGS}->[$level - 1] = $heading; |
| 515 | ## Reset subsection headings of this one to empty |
| 516 | for (my $i = $level; $i < $MAX_HEADING_LEVEL; ++$i) { |
| 517 | $myData{_SECTION_HEADINGS}->[$i] = ''; |
| 518 | } |
| 519 | } |
| 520 | |
| 521 | return $self->match_section(); |
| 522 | } |
| 523 | |
| 524 | ############################################################################# |
| 525 | |
| 526 | =head1 EXPORTED FUNCTIONS |
| 527 | |
| 528 | The following functions are exported by this module. Please note that |
| 529 | these are functions (not methods) and therefore C<do not> take an |
| 530 | implicit first argument. |
| 531 | |
| 532 | =cut |
| 533 | |
| 534 | ##--------------------------------------------------------------------------- |
| 535 | |
| 536 | =head1 B<podselect()> |
| 537 | |
| 538 | podselect(\%options,@filelist); |
| 539 | |
| 540 | B<podselect> will print the raw (untranslated) POD paragraphs of all |
| 541 | POD sections in the given input files specified by C<@filelist> |
| 542 | according to the given options. |
| 543 | |
| 544 | If any argument to B<podselect> is a reference to a hash |
| 545 | (associative array) then the values with the following keys are |
| 546 | processed as follows: |
| 547 | |
| 548 | =over 4 |
| 549 | |
| 550 | =item B<-output> |
| 551 | |
| 552 | A string corresponding to the desired output file (or ">&STDOUT" |
| 553 | or ">&STDERR"). The default is to use standard output. |
| 554 | |
| 555 | =item B<-sections> |
| 556 | |
| 557 | A reference to an array of sections specifications (as described in |
| 558 | L<"SECTION SPECIFICATIONS">) which indicate the desired set of POD |
| 559 | sections and subsections to be selected from input. If no section |
| 560 | specifications are given, then all sections of the PODs are used. |
| 561 | |
| 562 | =begin _NOT_IMPLEMENTED_ |
| 563 | |
| 564 | =item B<-ranges> |
| 565 | |
| 566 | A reference to an array of range specifications (as described in |
| 567 | L<"RANGE SPECIFICATIONS">) which indicate the desired range of POD |
| 568 | paragraphs to be selected from the desired input sections. If no range |
| 569 | specifications are given, then all paragraphs of the desired sections |
| 570 | are used. |
| 571 | |
| 572 | =end _NOT_IMPLEMENTED_ |
| 573 | |
| 574 | =back |
| 575 | |
| 576 | All other arguments should correspond to the names of input files |
| 577 | containing POD sections. A file name of "-" or "<&STDIN" will |
| 578 | be interpeted to mean standard input (which is the default if no |
| 579 | filenames are given). |
| 580 | |
| 581 | =cut |
| 582 | |
| 583 | sub podselect { |
| 584 | my(@argv) = @_; |
| 585 | my %defaults = (); |
| 586 | my $pod_parser = new Pod::Select(%defaults); |
| 587 | my $num_inputs = 0; |
| 588 | my $output = ">&STDOUT"; |
| 589 | my %opts; |
| 590 | local $_; |
| 591 | for (@argv) { |
| 592 | if (ref($_)) { |
| 593 | next unless (ref($_) eq 'HASH'); |
| 594 | %opts = (%defaults, %{$_}); |
| 595 | |
| 596 | ##------------------------------------------------------------- |
| 597 | ## Need this for backward compatibility since we formerly used |
| 598 | ## options that were all uppercase words rather than ones that |
| 599 | ## looked like Unix command-line options. |
| 600 | ## to be uppercase keywords) |
| 601 | ##------------------------------------------------------------- |
| 602 | %opts = map { |
| 603 | my ($key, $val) = (lc $_, $opts{$_}); |
| 604 | $key =~ s/^(?=\w)/-/; |
| 605 | $key =~ /^-se[cl]/ and $key = '-sections'; |
| 606 | #! $key eq '-range' and $key .= 's'; |
| 607 | ($key => $val); |
| 608 | } (keys %opts); |
| 609 | |
| 610 | ## Process the options |
| 611 | (exists $opts{'-output'}) and $output = $opts{'-output'}; |
| 612 | |
| 613 | ## Select the desired sections |
| 614 | $pod_parser->select(@{ $opts{'-sections'} }) |
| 615 | if ( (defined $opts{'-sections'}) |
| 616 | && ((ref $opts{'-sections'}) eq 'ARRAY') ); |
| 617 | |
| 618 | #! ## Select the desired paragraph ranges |
| 619 | #! $pod_parser->select(@{ $opts{'-ranges'} }) |
| 620 | #! if ( (defined $opts{'-ranges'}) |
| 621 | #! && ((ref $opts{'-ranges'}) eq 'ARRAY') ); |
| 622 | } |
| 623 | else { |
| 624 | $pod_parser->parse_from_file($_, $output); |
| 625 | ++$num_inputs; |
| 626 | } |
| 627 | } |
| 628 | $pod_parser->parse_from_file("-") unless ($num_inputs > 0); |
| 629 | } |
| 630 | |
| 631 | ############################################################################# |
| 632 | |
| 633 | =head1 PRIVATE METHODS AND DATA |
| 634 | |
| 635 | B<Pod::Select> makes uses a number of internal methods and data fields |
| 636 | which clients should not need to see or use. For the sake of avoiding |
| 637 | name collisions with client data and methods, these methods and fields |
| 638 | are briefly discussed here. Determined hackers may obtain further |
| 639 | information about them by reading the B<Pod::Select> source code. |
| 640 | |
| 641 | Private data fields are stored in the hash-object whose reference is |
| 642 | returned by the B<new()> constructor for this class. The names of all |
| 643 | private methods and data-fields used by B<Pod::Select> begin with a |
| 644 | prefix of "_" and match the regular expression C</^_\w+$/>. |
| 645 | |
| 646 | =cut |
| 647 | |
| 648 | ##--------------------------------------------------------------------------- |
| 649 | |
| 650 | =begin _PRIVATE_ |
| 651 | |
| 652 | =head1 B<_compile_section_spec()> |
| 653 | |
| 654 | $listref = $parser->_compile_section_spec($section_spec); |
| 655 | |
| 656 | This function (note it is a function and I<not> a method) takes a |
| 657 | section specification (as described in L<"SECTION SPECIFICATIONS">) |
| 658 | given in C<$section_sepc>, and compiles it into a list of regular |
| 659 | expressions. If C<$section_spec> has no syntax errors, then a reference |
| 660 | to the list (array) of corresponding regular expressions is returned; |
| 661 | otherwise C<undef> is returned and an error message is printed (using |
| 662 | B<carp>) for each invalid regex. |
| 663 | |
| 664 | =end _PRIVATE_ |
| 665 | |
| 666 | =cut |
| 667 | |
| 668 | sub _compile_section_spec { |
| 669 | my ($section_spec) = @_; |
| 670 | my (@regexs, $negated); |
| 671 | |
| 672 | ## Compile the spec into a list of regexs |
| 673 | local $_ = $section_spec; |
| 674 | s|\\\\|\001|g; ## handle escaped backward slashes |
| 675 | s|\\/|\002|g; ## handle escaped forward slashes |
| 676 | |
| 677 | ## Parse the regexs for the heading titles |
| 678 | @regexs = split('/', $_, $MAX_HEADING_LEVEL); |
| 679 | |
| 680 | ## Set default regex for ommitted levels |
| 681 | for (my $i = 0; $i < $MAX_HEADING_LEVEL; ++$i) { |
| 682 | $regexs[$i] = '.*' unless ((defined $regexs[$i]) |
| 683 | && (length $regexs[$i])); |
| 684 | } |
| 685 | ## Modify the regexs as needed and validate their syntax |
| 686 | my $bad_regexs = 0; |
| 687 | for (@regexs) { |
| 688 | $_ .= '.+' if ($_ eq '!'); |
| 689 | s|\001|\\\\|g; ## restore escaped backward slashes |
| 690 | s|\002|\\/|g; ## restore escaped forward slashes |
| 691 | $negated = s/^\!//; ## check for negation |
| 692 | eval "/$_/"; ## check regex syntax |
| 693 | if ($@) { |
| 694 | ++$bad_regexs; |
| 695 | carp "Bad regular expression /$_/ in \"$section_spec\": $@\n"; |
| 696 | } |
| 697 | else { |
| 698 | ## Add the forward and rear anchors (and put the negator back) |
| 699 | $_ = '^' . $_ unless (/^\^/); |
| 700 | $_ = $_ . '$' unless (/\$$/); |
| 701 | $_ = '!' . $_ if ($negated); |
| 702 | } |
| 703 | } |
| 704 | return (! $bad_regexs) ? [ @regexs ] : undef; |
| 705 | } |
| 706 | |
| 707 | ##--------------------------------------------------------------------------- |
| 708 | |
| 709 | =begin _PRIVATE_ |
| 710 | |
| 711 | =head2 $self->{_SECTION_HEADINGS} |
| 712 | |
| 713 | A reference to an array of the current section heading titles for each |
| 714 | heading level (note that the first heading level title is at index 0). |
| 715 | |
| 716 | =end _PRIVATE_ |
| 717 | |
| 718 | =cut |
| 719 | |
| 720 | ##--------------------------------------------------------------------------- |
| 721 | |
| 722 | =begin _PRIVATE_ |
| 723 | |
| 724 | =head2 $self->{_SELECTED_SECTIONS} |
| 725 | |
| 726 | A reference to an array of references to arrays. Each subarray is a list |
| 727 | of anchored regular expressions (preceded by a "!" if the expression is to |
| 728 | be negated). The index of the expression in the subarray should correspond |
| 729 | to the index of the heading title in C<$self-E<gt>{_SECTION_HEADINGS}> |
| 730 | that it is to be matched against. |
| 731 | |
| 732 | =end _PRIVATE_ |
| 733 | |
| 734 | =cut |
| 735 | |
| 736 | ############################################################################# |
| 737 | |
| 738 | =head1 SEE ALSO |
| 739 | |
| 740 | L<Pod::Parser> |
| 741 | |
| 742 | =head1 AUTHOR |
| 743 | |
| 744 | Please report bugs using L<http://rt.cpan.org>. |
| 745 | |
| 746 | Brad Appleton E<lt>bradapp@enteract.comE<gt> |
| 747 | |
| 748 | Based on code for B<pod2text> written by |
| 749 | Tom Christiansen E<lt>tchrist@mox.perl.comE<gt> |
| 750 | |
| 751 | =cut |
| 752 | |
| 753 | 1; |
| 754 | # vim: ts=4 sw=4 et |