doc/String.html

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  68                         <div id="method-list-section" class="section">
  69                                 <h3 class="section-header">Methods</h3>
  70                                 <ul class="link-list">
  71
  72                                         <li><a href="#method-i-porter2_ends_with_short_syllable%3F">#porter2_ends_with_short_syllable?</a></li>
  73
  74                                         <li><a href="#method-i-porter2_is_short_word%3F">#porter2_is_short_word?</a></li>
  75
  76                                         <li><a href="#method-i-porter2_postprocess">#porter2_postprocess</a></li>
  77
  78                                         <li><a href="#method-i-porter2_preprocess">#porter2_preprocess</a></li>
  79
  80                                         <li><a href="#method-i-porter2_r1">#porter2_r1</a></li>
  81
  82                                         <li><a href="#method-i-porter2_r2">#porter2_r2</a></li>
  83
  84                                         <li><a href="#method-i-porter2_stem">#porter2_stem</a></li>
  85
  86                                         <li><a href="#method-i-porter2_stem_verbose">#porter2_stem_verbose</a></li>
  87
  88                                         <li><a href="#method-i-porter2_step0">#porter2_step0</a></li>
  89
  90                                         <li><a href="#method-i-porter2_step1a">#porter2_step1a</a></li>
  91
  92                                         <li><a href="#method-i-porter2_step1b">#porter2_step1b</a></li>
  93
  94                                         <li><a href="#method-i-porter2_step1c">#porter2_step1c</a></li>
  95
  96                                         <li><a href="#method-i-porter2_step2">#porter2_step2</a></li>
  97
  98                                         <li><a href="#method-i-porter2_step3">#porter2_step3</a></li>
  99
 100                                         <li><a href="#method-i-porter2_step4">#porter2_step4</a></li>
 101
 102                                         <li><a href="#method-i-porter2_step5">#porter2_step5</a></li>
 103
 104                                         <li><a href="#method-i-porter2_tidy">#porter2_tidy</a></li>
 105
 106                                         <li><a href="#method-i-stem">#stem</a></li>
 107
 108                                 </ul>
 109                         </div>
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 142                                 <ul class="link-list">
 143
 144                                         <li><a href="./Porter2.html">Porter2</a></li>
 145
 146                                         <li><a href="./String.html">String</a></li>
 147
 148                                         <li><a href="./TestPorter2.html">TestPorter2</a></li>
 149
 150                                 </ul>
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 152                         </div>
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 155                 </div>
 156         </div>
 157
 158         <div id="documentation">
 159                 <h1 class="class">String</h1>
 160
 161                 <div id="description">
 162                         <p>
 163 Implementation of the Porter 2 stemmer. <a
 164 href="String.html#method-i-porter2_stem">String#porter2_stem</a> is the
 165 main stemming procedure.
 166 </p>
 167
 168                 </div>
 169
 170                 <!-- Constants -->
 171
 172
 173                 <!-- Attributes -->
 174
 175
 176                 <!-- Methods -->
 177
 178                 <div id="public-instance-method-details" class="method-section section">
 179                         <h3 class="section-header">Public Instance Methods</h3>
 180
 181
 182                         <div id="porter-ends-with-short-syllable--method" class="method-detail ">
 183                                 <a name="method-i-porter2_ends_with_short_syllable%3F"></a>
 184
 185                                 <div class="method-heading">
 186
 187                                         <span class="method-name">porter2_ends_with_short_syllable?</span><span
 188                                                 class="method-args">()</span>
 189                                         <span class="method-click-advice">click to toggle source</span>
 190
 191                                 </div>
 192
 193                                 <div class="method-description">
 194
 195                                         <p>
 196 Returns true if the word ends with a short syllable
 197 </p>
 198
 199
 200
 201                                         <div class="method-source-code"
 202                                                 id="porter-ends-with-short-syllable--source">
 203 <pre>
 204     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 59</span>
 205 59:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_ends_with_short_syllable?</span>
 206 60:     <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::SHORT_SYLLABLE}$/</span> <span class="ruby-operator">?</span> <span class="ruby-keyword kw">true</span> <span class="ruby-operator">:</span> <span class="ruby-keyword kw">false</span>
 207 61:   <span class="ruby-keyword kw">end</span></pre>
 208                                         </div>
 209
 210                                 </div>
 211
 212
 213
 214
 215                         </div>
 216
 217
 218                         <div id="porter-is-short-word--method" class="method-detail ">
 219                                 <a name="method-i-porter2_is_short_word%3F"></a>
 220
 221                                 <div class="method-heading">
 222
 223                                         <span class="method-name">porter2_is_short_word?</span><span
 224                                                 class="method-args">()</span>
 225                                         <span class="method-click-advice">click to toggle source</span>
 226
 227                                 </div>
 228
 229                                 <div class="method-description">
 230
 231                                         <p>
 232 A word is short if it ends in a short syllable, and R1 is null
 233 </p>
 234
 235
 236
 237                                         <div class="method-source-code"
 238                                                 id="porter-is-short-word--source">
 239 <pre>
 240     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 65</span>
 241 65:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_is_short_word?</span>
 242 66:     <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_ends_with_short_syllable?</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span>.<span class="ruby-identifier">empty?</span>
 243 67:   <span class="ruby-keyword kw">end</span></pre>
 244                                         </div>
 245
 246                                 </div>
 247
 248
 249
 250
 251                         </div>
 252
 253
 254                         <div id="porter-postprocess-method" class="method-detail ">
 255                                 <a name="method-i-porter2_postprocess"></a>
 256
 257                                 <div class="method-heading">
 258
 259                                         <span class="method-name">porter2_postprocess</span><span
 260                                                 class="method-args">()</span>
 261                                         <span class="method-click-advice">click to toggle source</span>
 262
 263                                 </div>
 264
 265                                 <div class="method-description">
 266
 267                                         <p>
 268 Turn all Y letters into y
 269 </p>
 270
 271
 272
 273                                         <div class="method-source-code"
 274                                                 id="porter-postprocess-source">
 275 <pre>
 276      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 261</span>
 277 261:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_postprocess</span>
 278 262:     <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">gsub</span>(<span class="ruby-regexp re">/Y/</span>, <span class="ruby-value str">'y'</span>)
 279 263:   <span class="ruby-keyword kw">end</span></pre>
 280                                         </div>
 281
 282                                 </div>
 283
 284
 285
 286
 287                         </div>
 288
 289
 290                         <div id="porter-preprocess-method" class="method-detail ">
 291                                 <a name="method-i-porter2_preprocess"></a>
 292
 293                                 <div class="method-heading">
 294
 295                                         <span class="method-name">porter2_preprocess</span><span
 296                                                 class="method-args">()</span>
 297                                         <span class="method-click-advice">click to toggle source</span>
 298
 299                                 </div>
 300
 301                                 <div class="method-description">
 302
 303                                         <p>
 304 Preprocess the word.  Remove any initial &#8217;, if present. Then, set
 305 initial y, or y after a vowel, to Y
 306 </p>
 307 <p>
 308 (The comment to &#8216;establish the regions R1 and R2&#8217; in the
 309 original description  is an implementation optimisation that identifies
 310 where the regions start. As no modifications are made to the word that
 311 affect those positions, you may want to cache them now. This implementation
 312 doesn&#8217;t do that.)
 313 </p>
 314
 315
 316
 317                                         <div class="method-source-code"
 318                                                 id="porter-preprocess-source">
 319 <pre>
 320     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 25</span>
 321 25:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_preprocess</span>
 322 26:     <span class="ruby-identifier">w</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">dup</span>
 323 27:
 324 28:     <span class="ruby-comment cmt"># remove any initial apostrophe</span>
 325 29:     <span class="ruby-identifier">w</span>.<span class="ruby-identifier">gsub!</span>(<span class="ruby-regexp re">/^'*(.)/</span>, <span class="ruby-value str">'\1'</span>)
 326 30:
 327 31:     <span class="ruby-comment cmt"># set initial y, or y after a vowel, to Y</span>
 328 32:     <span class="ruby-identifier">w</span>.<span class="ruby-identifier">gsub!</span>(<span class="ruby-regexp re">/^y/</span>, <span class="ruby-value str">&quot;Y&quot;</span>)
 329 33:     <span class="ruby-identifier">w</span>.<span class="ruby-identifier">gsub!</span>(<span class="ruby-node">/(#{Porter2::V})y/</span>, <span class="ruby-value str">'\1Y'</span>)
 330 34:
 331 35:     <span class="ruby-identifier">w</span>
 332 36:   <span class="ruby-keyword kw">end</span></pre>
 333                                         </div>
 334
 335                                 </div>
 336
 337
 338
 339
 340                         </div>
 341
 342
 343                         <div id="porter-r--method" class="method-detail ">
 344                                 <a name="method-i-porter2_r1"></a>
 345
 346                                 <div class="method-heading">
 347
 348                                         <span class="method-name">porter2_r1</span><span
 349                                                 class="method-args">()</span>
 350                                         <span class="method-click-advice">click to toggle source</span>
 351
 352                                 </div>
 353
 354                                 <div class="method-description">
 355
 356                                         <p>
 357 R1 is the portion of the word after the first non-vowel after the first
 358 vowel (with words beginning &#8216;gener-&#8217;, &#8216;commun-&#8217;,
 359 and &#8216;arsen-&#8217; treated as special cases
 360 </p>
 361
 362
 363
 364                                         <div class="method-source-code"
 365                                                 id="porter-r--source">
 366 <pre>
 367     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 41</span>
 368 41:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_r1</span>
 369 42:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/^(gener|commun|arsen)(?&lt;r1&gt;.*)/</span>
 370 43:       <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">last_match</span>(<span class="ruby-value">:r1</span>)
 371 44:     <span class="ruby-keyword kw">else</span>
 372 45:       <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::V}#{Porter2::C}(?&lt;r1&gt;.*)$/</span>
 373 46:       <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">last_match</span>(<span class="ruby-value">:r1</span>) <span class="ruby-operator">||</span> <span class="ruby-value str">&quot;&quot;</span>
 374 47:     <span class="ruby-keyword kw">end</span>
 375 48:   <span class="ruby-keyword kw">end</span></pre>
 376                                         </div>
 377
 378                                 </div>
 379
 380
 381
 382
 383                         </div>
 384
 385
 386                         <div id="porter-r--method" class="method-detail ">
 387                                 <a name="method-i-porter2_r2"></a>
 388
 389                                 <div class="method-heading">
 390
 391                                         <span class="method-name">porter2_r2</span><span
 392                                                 class="method-args">()</span>
 393                                         <span class="method-click-advice">click to toggle source</span>
 394
 395                                 </div>
 396
 397                                 <div class="method-description">
 398
 399                                         <p>
 400 R2 is the portion of R1 (<a
 401 href="String.html#method-i-porter2_r1">porter2_r1</a>) after the first
 402 non-vowel after the first vowel
 403 </p>
 404
 405
 406
 407                                         <div class="method-source-code"
 408                                                 id="porter-r--source">
 409 <pre>
 410     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 52</span>
 411 52:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_r2</span>
 412 53:     <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::V}#{Porter2::C}(?&lt;r2&gt;.*)$/</span>
 413 54:     <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">last_match</span>(<span class="ruby-value">:r2</span>) <span class="ruby-operator">||</span> <span class="ruby-value str">&quot;&quot;</span>
 414 55:   <span class="ruby-keyword kw">end</span></pre>
 415                                         </div>
 416
 417                                 </div>
 418
 419
 420
 421
 422                         </div>
 423
 424
 425                         <div id="porter-stem-method" class="method-detail ">
 426                                 <a name="method-i-porter2_stem"></a>
 427
 428                                 <div class="method-heading">
 429
 430                                         <span class="method-name">porter2_stem</span><span
 431                                                 class="method-args">(gb_english = false)</span>
 432                                         <span class="method-click-advice">click to toggle source</span>
 433
 434                                 </div>
 435
 436                                 <div class="method-description">
 437
 438                                         <p>
 439 Perform the stemming procedure. If <tt>gb_english</tt> is true, treat
 440 &#8217;-ise&#8217; and similar suffixes as &#8217;-ize&#8217; in American
 441 English.
 442 </p>
 443
 444
 445
 446                                         <div class="method-source-code"
 447                                                 id="porter-stem-source">
 448 <pre>
 449      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 269</span>
 450 269:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_stem</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 451 270:     <span class="ruby-identifier">preword</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_tidy</span>
 452 271:     <span class="ruby-keyword kw">return</span> <span class="ruby-identifier">preword</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">length</span> <span class="ruby-operator">&lt;=</span> <span class="ruby-value">2</span>
 453 272:
 454 273:     <span class="ruby-identifier">word</span> = <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">porter2_preprocess</span>
 455 274:
 456 275:     <span class="ruby-keyword kw">if</span> <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">SPECIAL_CASES</span>.<span class="ruby-identifier">has_key?</span> <span class="ruby-identifier">word</span>
 457 276:       <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">SPECIAL_CASES</span>[<span class="ruby-identifier">word</span>]
 458 277:     <span class="ruby-keyword kw">else</span>
 459 278:       <span class="ruby-identifier">w1a</span> = <span class="ruby-identifier">word</span>.<span class="ruby-identifier">porter2_step0</span>.<span class="ruby-identifier">porter2_step1a</span>
 460 279:       <span class="ruby-keyword kw">if</span> <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">STEP_1A_SPECIAL_CASES</span>.<span class="ruby-identifier">include?</span> <span class="ruby-identifier">w1a</span>
 461 280:         <span class="ruby-identifier">w1a</span>
 462 281:       <span class="ruby-keyword kw">else</span>
 463 282:         <span class="ruby-identifier">w1a</span>.<span class="ruby-identifier">porter2_step1b</span>(<span class="ruby-identifier">gb_english</span>).<span class="ruby-identifier">porter2_step1c</span>.<span class="ruby-identifier">porter2_step2</span>(<span class="ruby-identifier">gb_english</span>).<span class="ruby-identifier">porter2_step3</span>(<span class="ruby-identifier">gb_english</span>).<span class="ruby-identifier">porter2_step4</span>(<span class="ruby-identifier">gb_english</span>).<span class="ruby-identifier">porter2_step5</span>.<span class="ruby-identifier">porter2_postprocess</span>
 464 283:       <span class="ruby-keyword kw">end</span>
 465 284:     <span class="ruby-keyword kw">end</span>
 466 285:   <span class="ruby-keyword kw">end</span></pre>
 467                                         </div>
 468
 469                                 </div>
 470
 471
 472                                 <div class="aliases">
 473                                         Also aliased as: <a href="String.html#method-i-stem">stem</a>
 474                                 </div>
 475
 476
 477
 478                         </div>
 479
 480
 481                         <div id="porter-stem-verbose-method" class="method-detail ">
 482                                 <a name="method-i-porter2_stem_verbose"></a>
 483
 484                                 <div class="method-heading">
 485
 486                                         <span class="method-name">porter2_stem_verbose</span><span
 487                                                 class="method-args">(gb_english = false)</span>
 488                                         <span class="method-click-advice">click to toggle source</span>
 489
 490                                 </div>
 491
 492                                 <div class="method-description">
 493
 494                                         <p>
 495 A verbose version of <a
 496 href="String.html#method-i-porter2_stem">porter2_stem</a> that prints the
 497 output of each stage to STDOUT
 498 </p>
 499
 500
 501
 502                                         <div class="method-source-code"
 503                                                 id="porter-stem-verbose-source">
 504 <pre>
 505      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 288</span>
 506 288:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_stem_verbose</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 507 289:     <span class="ruby-identifier">preword</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_tidy</span>
 508 290:     <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;Preword: #{preword}&quot;</span>
 509 291:     <span class="ruby-keyword kw">return</span> <span class="ruby-identifier">preword</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">length</span> <span class="ruby-operator">&lt;=</span> <span class="ruby-value">2</span>
 510 292:
 511 293:     <span class="ruby-identifier">word</span> = <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">porter2_preprocess</span>
 512 294:     <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;Preprocessed: #{word}&quot;</span>
 513 295:
 514 296:     <span class="ruby-keyword kw">if</span> <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">SPECIAL_CASES</span>.<span class="ruby-identifier">has_key?</span> <span class="ruby-identifier">word</span>
 515 297:       <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;Returning #{word} as special case #{Porter2::SPECIAL_CASES[word]}&quot;</span>
 516 298:       <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">SPECIAL_CASES</span>[<span class="ruby-identifier">word</span>]
 517 299:     <span class="ruby-keyword kw">else</span>
 518 300:       <span class="ruby-identifier">r1</span> = <span class="ruby-identifier">word</span>.<span class="ruby-identifier">porter2_r1</span>
 519 301:       <span class="ruby-identifier">r2</span> = <span class="ruby-identifier">word</span>.<span class="ruby-identifier">porter2_r2</span>
 520 302:       <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;R1 = #{r1}, R2 = #{r2}&quot;</span>
 521 303:
 522 304:       <span class="ruby-identifier">w0</span> = <span class="ruby-identifier">word</span>.<span class="ruby-identifier">porter2_step0</span> ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 0:  #{w0} (R1 = #{w0.porter2_r1}, R2 = #{w0.porter2_r2})&quot;</span>
 523 305:       <span class="ruby-identifier">w1a</span> = <span class="ruby-identifier">w0</span>.<span class="ruby-identifier">porter2_step1a</span> ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 1a: #{w1a} (R1 = #{w1a.porter2_r1}, R2 = #{w1a.porter2_r2})&quot;</span>
 524 306:
 525 307:       <span class="ruby-keyword kw">if</span> <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">STEP_1A_SPECIAL_CASES</span>.<span class="ruby-identifier">include?</span> <span class="ruby-identifier">w1a</span>
 526 308:         <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;Returning #{w1a} as 1a special case&quot;</span>
 527 309:         <span class="ruby-identifier">w1a</span>
 528 310:       <span class="ruby-keyword kw">else</span>
 529 311:         <span class="ruby-identifier">w1b</span> = <span class="ruby-identifier">w1a</span>.<span class="ruby-identifier">porter2_step1b</span>(<span class="ruby-identifier">gb_english</span>) ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 1b: #{w1b} (R1 = #{w1b.porter2_r1}, R2 = #{w1b.porter2_r2})&quot;</span>
 530 312:         <span class="ruby-identifier">w1c</span> = <span class="ruby-identifier">w1b</span>.<span class="ruby-identifier">porter2_step1c</span> ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 1c: #{w1c} (R1 = #{w1c.porter2_r1}, R2 = #{w1c.porter2_r2})&quot;</span>
 531 313:         <span class="ruby-identifier">w2</span> = <span class="ruby-identifier">w1c</span>.<span class="ruby-identifier">porter2_step2</span>(<span class="ruby-identifier">gb_english</span>) ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 2:  #{w2} (R1 = #{w2.porter2_r1}, R2 = #{w2.porter2_r2})&quot;</span>
 532 314:         <span class="ruby-identifier">w3</span> = <span class="ruby-identifier">w2</span>.<span class="ruby-identifier">porter2_step3</span>(<span class="ruby-identifier">gb_english</span>) ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 3:  #{w3} (R1 = #{w3.porter2_r1}, R2 = #{w3.porter2_r2})&quot;</span>
 533 315:         <span class="ruby-identifier">w4</span> = <span class="ruby-identifier">w3</span>.<span class="ruby-identifier">porter2_step4</span>(<span class="ruby-identifier">gb_english</span>) ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 4:  #{w4} (R1 = #{w4.porter2_r1}, R2 = #{w4.porter2_r2})&quot;</span>
 534 316:         <span class="ruby-identifier">w5</span> = <span class="ruby-identifier">w4</span>.<span class="ruby-identifier">porter2_step5</span> ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After step 5:  #{w5}&quot;</span>
 535 317:         <span class="ruby-identifier">wpost</span> = <span class="ruby-identifier">w5</span>.<span class="ruby-identifier">porter2_postprocess</span> ; <span class="ruby-identifier">puts</span> <span class="ruby-node">&quot;After postprocess: #{wpost}&quot;</span>
 536 318:         <span class="ruby-identifier">wpost</span>
 537 319:       <span class="ruby-keyword kw">end</span>
 538 320:     <span class="ruby-keyword kw">end</span>
 539 321:   <span class="ruby-keyword kw">end</span></pre>
 540                                         </div>
 541
 542                                 </div>
 543
 544
 545
 546
 547                         </div>
 548
 549
 550                         <div id="porter-step--method" class="method-detail ">
 551                                 <a name="method-i-porter2_step0"></a>
 552
 553                                 <div class="method-heading">
 554
 555                                         <span class="method-name">porter2_step0</span><span
 556                                                 class="method-args">()</span>
 557                                         <span class="method-click-advice">click to toggle source</span>
 558
 559                                 </div>
 560
 561                                 <div class="method-description">
 562
 563                                         <p>
 564 Search for the longest among the suffixes,
 565 </p>
 566 <ul>
 567 <li><p>
 568 &#8216;
 569 </p>
 570 </li>
 571 <li><p>
 572 &#8217;s
 573 </p>
 574 </li>
 575 <li><p>
 576 &#8217;s&#8217;
 577 </p>
 578 </li>
 579 </ul>
 580 <p>
 581 and remove if found.
 582 </p>
 583
 584
 585
 586                                         <div class="method-source-code"
 587                                                 id="porter-step--source">
 588 <pre>
 589     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 75</span>
 590 75:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step0</span>
 591 76:     <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub!</span>(<span class="ruby-regexp re">/(.)('s'|'s|')$/</span>, <span class="ruby-value str">'\1'</span>) <span class="ruby-operator">||</span> <span class="ruby-keyword kw">self</span>
 592 77:   <span class="ruby-keyword kw">end</span></pre>
 593                                         </div>
 594
 595                                 </div>
 596
 597
 598
 599
 600                         </div>
 601
 602
 603                         <div id="porter-step-a-method" class="method-detail ">
 604                                 <a name="method-i-porter2_step1a"></a>
 605
 606                                 <div class="method-heading">
 607
 608                                         <span class="method-name">porter2_step1a</span><span
 609                                                 class="method-args">()</span>
 610                                         <span class="method-click-advice">click to toggle source</span>
 611
 612                                 </div>
 613
 614                                 <div class="method-description">
 615
 616                                         <p>
 617 Search for the longest among the following suffixes, and perform the action
 618 indicated.
 619 </p>
 620 <table>
 621 <tr><td valign="top">sses</td><td><p>
 622 replace by ss
 623 </p>
 624 </td></tr>
 625 <tr><td valign="top">ied, ies</td><td><p>
 626 replace by i if preceded by more than one letter, otherwise by ie
 627 </p>
 628 </td></tr>
 629 <tr><td valign="top">s</td><td><p>
 630 delete if the preceding word part contains a vowel not immediately before
 631 the s
 632 </p>
 633 </td></tr>
 634 <tr><td valign="top">us, ss</td><td><p>
 635 do nothing
 636 </p>
 637 </td></tr>
 638 </table>
 639
 640
 641
 642                                         <div class="method-source-code"
 643                                                 id="porter-step-a-source">
 644 <pre>
 645      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 85</span>
 646  85:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step1a</span>
 647  86:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/sses$/</span>
 648  87:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/sses$/</span>, <span class="ruby-value str">'ss'</span>)
 649  88:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/..(ied|ies)$/</span>
 650  89:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/(ied|ies)$/</span>, <span class="ruby-value str">'i'</span>)
 651  90:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(ied|ies)$/</span>
 652  91:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/(ied|ies)$/</span>, <span class="ruby-value str">'ie'</span>)
 653  92:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(us|ss)$/</span>
 654  93:       <span class="ruby-keyword kw">self</span>
 655  94:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/s$/</span>
 656  95:       <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/(#{Porter2::V}.+)s$/</span>
 657  96:         <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/s$/</span>, <span class="ruby-value str">''</span>)
 658  97:       <span class="ruby-keyword kw">else</span>
 659  98:         <span class="ruby-keyword kw">self</span>
 660  99:       <span class="ruby-keyword kw">end</span>
 661 100:     <span class="ruby-keyword kw">else</span>
 662 101:       <span class="ruby-keyword kw">self</span>
 663 102:     <span class="ruby-keyword kw">end</span>
 664 103:   <span class="ruby-keyword kw">end</span></pre>
 665                                         </div>
 666
 667                                 </div>
 668
 669
 670
 671
 672                         </div>
 673
 674
 675                         <div id="porter-step-b-method" class="method-detail ">
 676                                 <a name="method-i-porter2_step1b"></a>
 677
 678                                 <div class="method-heading">
 679
 680                                         <span class="method-name">porter2_step1b</span><span
 681                                                 class="method-args">(gb_english = false)</span>
 682                                         <span class="method-click-advice">click to toggle source</span>
 683
 684                                 </div>
 685
 686                                 <div class="method-description">
 687
 688                                         <p>
 689 Search for the longest among the following suffixes, and perform the action
 690 indicated.
 691 </p>
 692 <table>
 693 <tr><td valign="top">eed, eedly</td><td><p>
 694 replace by ee if the suffix is also in R1
 695 </p>
 696 </td></tr>
 697 <tr><td valign="top">ed, edly, ing, ingly</td><td><p>
 698 delete if the preceding word part contains a vowel and,  after the
 699 deletion:
 700 </p>
 701 <ul>
 702 <li><p>
 703 if the word ends at, bl or iz: add e, or
 704 </p>
 705 </li>
 706 </ul>
 707 <ul>
 708 <li><p>
 709 if the word ends with a double: remove the last letter, or
 710 </p>
 711 </li>
 712 </ul>
 713 <ul>
 714 <li><p>
 715 if the word is short: add e
 716 </p>
 717 </li>
 718 </ul>
 719 </td></tr>
 720 </table>
 721 <p>
 722 (If gb_english is <tt>true</tt>, treat the &#8216;is&#8217; suffix as
 723 &#8216;iz&#8217; above.)
 724 </p>
 725
 726
 727
 728                                         <div class="method-source-code"
 729                                                 id="porter-step-b-source">
 730 <pre>
 731      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 115</span>
 732 115:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step1b</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 733 116:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(eed|eedly)$/</span>
 734 117:       <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(eed|eedly)$/</span>
 735 118:         <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/(eed|eedly)$/</span>, <span class="ruby-value str">'ee'</span>)
 736 119:       <span class="ruby-keyword kw">else</span>
 737 120:         <span class="ruby-keyword kw">self</span>
 738 121:       <span class="ruby-keyword kw">end</span>
 739 122:     <span class="ruby-keyword kw">else</span>
 740 123:       <span class="ruby-identifier">w</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">dup</span>
 741 124:       <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">w</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::V}.*(ed|edly|ing|ingly)$/</span>
 742 125:         <span class="ruby-identifier">w</span>.<span class="ruby-identifier">sub!</span>(<span class="ruby-regexp re">/(ed|edly|ing|ingly)$/</span>, <span class="ruby-value str">''</span>)
 743 126:         <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">w</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(at|lb|iz)$/</span>
 744 127:           <span class="ruby-identifier">w</span> <span class="ruby-operator">+=</span> <span class="ruby-value str">'e'</span>
 745 128:         <span class="ruby-keyword kw">elsif</span> <span class="ruby-identifier">w</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/is$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-identifier">gb_english</span>
 746 129:           <span class="ruby-identifier">w</span> <span class="ruby-operator">+=</span> <span class="ruby-value str">'e'</span>
 747 130:         <span class="ruby-keyword kw">elsif</span> <span class="ruby-identifier">w</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::Double}$/</span>
 748 131:           <span class="ruby-identifier">w</span>.<span class="ruby-identifier">chop!</span>
 749 132:         <span class="ruby-keyword kw">elsif</span> <span class="ruby-identifier">w</span>.<span class="ruby-identifier">porter2_is_short_word?</span>
 750 133:           <span class="ruby-identifier">w</span> <span class="ruby-operator">+=</span> <span class="ruby-value str">'e'</span>
 751 134:         <span class="ruby-keyword kw">end</span>
 752 135:       <span class="ruby-keyword kw">end</span>
 753 136:       <span class="ruby-identifier">w</span>
 754 137:     <span class="ruby-keyword kw">end</span>
 755 138:   <span class="ruby-keyword kw">end</span></pre>
 756                                         </div>
 757
 758                                 </div>
 759
 760
 761
 762
 763                         </div>
 764
 765
 766                         <div id="porter-step-c-method" class="method-detail ">
 767                                 <a name="method-i-porter2_step1c"></a>
 768
 769                                 <div class="method-heading">
 770
 771                                         <span class="method-name">porter2_step1c</span><span
 772                                                 class="method-args">()</span>
 773                                         <span class="method-click-advice">click to toggle source</span>
 774
 775                                 </div>
 776
 777                                 <div class="method-description">
 778
 779                                         <p>
 780 Replace a suffix of y or Y by i if it is preceded by a non-vowel which is
 781 not the first letter of the word.
 782 </p>
 783
 784
 785
 786                                         <div class="method-source-code"
 787                                                 id="porter-step-c-source">
 788 <pre>
 789      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 143</span>
 790 143:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step1c</span>
 791 144:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/.+#{Porter2::C}(y|Y)$/</span>
 792 145:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/(y|Y)$/</span>, <span class="ruby-value str">'i'</span>)
 793 146:     <span class="ruby-keyword kw">else</span>
 794 147:       <span class="ruby-keyword kw">self</span>
 795 148:     <span class="ruby-keyword kw">end</span>
 796 149:   <span class="ruby-keyword kw">end</span></pre>
 797                                         </div>
 798
 799                                 </div>
 800
 801
 802
 803
 804                         </div>
 805
 806
 807                         <div id="porter-step--method" class="method-detail ">
 808                                 <a name="method-i-porter2_step2"></a>
 809
 810                                 <div class="method-heading">
 811
 812                                         <span class="method-name">porter2_step2</span><span
 813                                                 class="method-args">(gb_english = false)</span>
 814                                         <span class="method-click-advice">click to toggle source</span>
 815
 816                                 </div>
 817
 818                                 <div class="method-description">
 819
 820                                         <p>
 821 Search for the longest among the suffixes listed in the keys of
 822 Porter2::STEP_2_MAPS.  If one is found and that suffix occurs in R1,
 823 replace it with the value  found in STEP_2_MAPS.
 824 </p>
 825 <p>
 826 (Suffixes &#8216;ogi&#8217; and &#8216;li&#8217; are treated as special
 827 cases in the procedure.)
 828 </p>
 829 <p>
 830 (If gb_english is <tt>true</tt>, replace the &#8216;iser&#8217; and
 831 &#8216;isation&#8217; suffixes with &#8216;ise&#8217;, similarly to how
 832 &#8216;izer&#8217; and &#8216;ization&#8217; are treated.)
 833 </p>
 834
 835
 836
 837                                         <div class="method-source-code"
 838                                                 id="porter-step--source">
 839 <pre>
 840      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 160</span>
 841 160:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step2</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 842 161:     <span class="ruby-identifier">r1</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span>
 843 162:     <span class="ruby-identifier">s2m</span> = <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">STEP_2_MAPS</span>.<span class="ruby-identifier">dup</span>
 844 163:     <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">gb_english</span>
 845 164:       <span class="ruby-identifier">s2m</span>[<span class="ruby-value str">&quot;iser&quot;</span>] = <span class="ruby-value str">&quot;ise&quot;</span>
 846 165:       <span class="ruby-identifier">s2m</span>[<span class="ruby-value str">&quot;isation&quot;</span>] = <span class="ruby-value str">&quot;ise&quot;</span>
 847 166:     <span class="ruby-keyword kw">end</span>
 848 167:     <span class="ruby-identifier">step_2_re</span> = <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">union</span>(<span class="ruby-identifier">s2m</span>.<span class="ruby-identifier">keys</span>.<span class="ruby-identifier">map</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">r</span><span class="ruby-operator">|</span> <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">r</span> <span class="ruby-operator">+</span> <span class="ruby-value str">&quot;$&quot;</span>)})
 849 168:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-identifier">step_2_re</span>
 850 169:       <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">r1</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{$&amp;}$/</span>
 851 170:         <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-node">/#{$&amp;}$/</span>, <span class="ruby-identifier">s2m</span>[<span class="ruby-node">$&amp;</span>])
 852 171:       <span class="ruby-keyword kw">else</span>
 853 172:         <span class="ruby-keyword kw">self</span>
 854 173:       <span class="ruby-keyword kw">end</span>
 855 174:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-identifier">r1</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/li$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/(#{Porter2::Valid_LI})li$/</span>
 856 175:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/li$/</span>, <span class="ruby-value str">''</span>)
 857 176:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-identifier">r1</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/ogi$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/logi$/</span>
 858 177:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/ogi$/</span>, <span class="ruby-value str">'og'</span>)
 859 178:     <span class="ruby-keyword kw">else</span>
 860 179:       <span class="ruby-keyword kw">self</span>
 861 180:     <span class="ruby-keyword kw">end</span>
 862 181:   <span class="ruby-keyword kw">end</span></pre>
 863                                         </div>
 864
 865                                 </div>
 866
 867
 868
 869
 870                         </div>
 871
 872
 873                         <div id="porter-step--method" class="method-detail ">
 874                                 <a name="method-i-porter2_step3"></a>
 875
 876                                 <div class="method-heading">
 877
 878                                         <span class="method-name">porter2_step3</span><span
 879                                                 class="method-args">(gb_english = false)</span>
 880                                         <span class="method-click-advice">click to toggle source</span>
 881
 882                                 </div>
 883
 884                                 <div class="method-description">
 885
 886                                         <p>
 887 Search for the longest among the suffixes listed in the keys of
 888 Porter2::STEP_3_MAPS.  If one is found and that suffix occurs in R1,
 889 replace it with the value  found in STEP_3_MAPS.
 890 </p>
 891 <p>
 892 (Suffix &#8216;ative&#8217; is treated as a special case in the procedure.)
 893 </p>
 894 <p>
 895 (If gb_english is <tt>true</tt>, replace the &#8216;alise&#8217; suffix
 896 with &#8216;al&#8217;, similarly to how &#8216;alize&#8217; is treated.)
 897 </p>
 898
 899
 900
 901                                         <div class="method-source-code"
 902                                                 id="porter-step--source">
 903 <pre>
 904      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 192</span>
 905 192:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step3</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 906 193:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/ative$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r2</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/ative$/</span>
 907 194:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/ative$/</span>, <span class="ruby-value str">''</span>)
 908 195:     <span class="ruby-keyword kw">else</span>
 909 196:       <span class="ruby-identifier">s3m</span> = <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">STEP_3_MAPS</span>.<span class="ruby-identifier">dup</span>
 910 197:       <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">gb_english</span>
 911 198:         <span class="ruby-identifier">s3m</span>[<span class="ruby-value str">&quot;alise&quot;</span>] = <span class="ruby-value str">&quot;al&quot;</span>
 912 199:       <span class="ruby-keyword kw">end</span>
 913 200:       <span class="ruby-identifier">step_3_re</span> = <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">union</span>(<span class="ruby-identifier">s3m</span>.<span class="ruby-identifier">keys</span>.<span class="ruby-identifier">map</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">r</span><span class="ruby-operator">|</span> <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">r</span> <span class="ruby-operator">+</span> <span class="ruby-value str">&quot;$&quot;</span>)})
 914 201:       <span class="ruby-identifier">r1</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span>
 915 202:       <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-identifier">step_3_re</span> <span class="ruby-keyword kw">and</span> <span class="ruby-identifier">r1</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{$&amp;}$/</span>
 916 203:         <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-node">/#{$&amp;}$/</span>, <span class="ruby-identifier">s3m</span>[<span class="ruby-node">$&amp;</span>])
 917 204:       <span class="ruby-keyword kw">else</span>
 918 205:         <span class="ruby-keyword kw">self</span>
 919 206:       <span class="ruby-keyword kw">end</span>
 920 207:     <span class="ruby-keyword kw">end</span>
 921 208:   <span class="ruby-keyword kw">end</span></pre>
 922                                         </div>
 923
 924                                 </div>
 925
 926
 927
 928
 929                         </div>
 930
 931
 932                         <div id="porter-step--method" class="method-detail ">
 933                                 <a name="method-i-porter2_step4"></a>
 934
 935                                 <div class="method-heading">
 936
 937                                         <span class="method-name">porter2_step4</span><span
 938                                                 class="method-args">(gb_english = false)</span>
 939                                         <span class="method-click-advice">click to toggle source</span>
 940
 941                                 </div>
 942
 943                                 <div class="method-description">
 944
 945                                         <p>
 946 Search for the longest among the suffixes listed in the keys of
 947 Porter2::STEP_4_MAPS.  If one is found and that suffix occurs in R2,
 948 replace it with the value  found in STEP_4_MAPS.
 949 </p>
 950 <p>
 951 (Suffix &#8216;ion&#8217; is treated as a special case in the procedure.)
 952 </p>
 953 <p>
 954 (If gb_english is <tt>true</tt>, delete the &#8216;ise&#8217; suffix if
 955 found.)
 956 </p>
 957
 958
 959
 960                                         <div class="method-source-code"
 961                                                 id="porter-step--source">
 962 <pre>
 963      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 218</span>
 964 218:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step4</span>(<span class="ruby-identifier">gb_english</span> = <span class="ruby-keyword kw">false</span>)
 965 219:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r2</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/ion$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/(s|t)ion$/</span>
 966 220:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/ion$/</span>, <span class="ruby-value str">''</span>)
 967 221:     <span class="ruby-keyword kw">else</span>
 968 222:       <span class="ruby-identifier">s4m</span> = <span class="ruby-constant">Porter2</span><span class="ruby-operator">::</span><span class="ruby-constant">STEP_4_MAPS</span>.<span class="ruby-identifier">dup</span>
 969 223:       <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">gb_english</span>
 970 224:         <span class="ruby-identifier">s4m</span>[<span class="ruby-value str">&quot;ise&quot;</span>] = <span class="ruby-value str">&quot;&quot;</span>
 971 225:       <span class="ruby-keyword kw">end</span>
 972 226:       <span class="ruby-identifier">step_4_re</span> = <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">union</span>(<span class="ruby-identifier">s4m</span>.<span class="ruby-identifier">keys</span>.<span class="ruby-identifier">map</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">r</span><span class="ruby-operator">|</span> <span class="ruby-constant">Regexp</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">r</span> <span class="ruby-operator">+</span> <span class="ruby-value str">&quot;$&quot;</span>)})
 973 227:       <span class="ruby-identifier">r2</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r2</span>
 974 228:       <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-identifier">step_4_re</span>
 975 229:         <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">r2</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{$&amp;}/</span>
 976 230:           <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-node">/#{$&amp;}$/</span>, <span class="ruby-identifier">s4m</span>[<span class="ruby-node">$&amp;</span>])
 977 231:         <span class="ruby-keyword kw">else</span>
 978 232:           <span class="ruby-keyword kw">self</span>
 979 233:         <span class="ruby-keyword kw">end</span>
 980 234:       <span class="ruby-keyword kw">else</span>
 981 235:         <span class="ruby-keyword kw">self</span>
 982 236:       <span class="ruby-keyword kw">end</span>
 983 237:     <span class="ruby-keyword kw">end</span>
 984 238:   <span class="ruby-keyword kw">end</span></pre>
 985                                         </div>
 986
 987                                 </div>
 988
 989
 990
 991
 992                         </div>
 993
 994
 995                         <div id="porter-step--method" class="method-detail ">
 996                                 <a name="method-i-porter2_step5"></a>
 997
 998                                 <div class="method-heading">
 999
1000                                         <span class="method-name">porter2_step5</span><span
1001                                                 class="method-args">()</span>
1002                                         <span class="method-click-advice">click to toggle source</span>
1003
1004                                 </div>
1005
1006                                 <div class="method-description">
1007
1008                                         <p>
1009 Search for the the following suffixes, and, if found, perform the action
1010 indicated.
1011 </p>
1012 <table>
1013 <tr><td valign="top">e</td><td><p>
1014 delete if in R2, or in R1 and not preceded by a short syllable
1015 </p>
1016 </td></tr>
1017 <tr><td valign="top">l</td><td><p>
1018 delete if in R2 and preceded by l
1019 </p>
1020 </td></tr>
1021 </table>
1022
1023
1024
1025                                         <div class="method-source-code"
1026                                                 id="porter-step--source">
1027 <pre>
1028      <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 244</span>
1029 244:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_step5</span>
1030 245:     <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/ll$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r2</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/l$/</span>
1031 246:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/ll$/</span>, <span class="ruby-value str">'l'</span>)
1032 247:     <span class="ruby-keyword kw">elsif</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/e$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r2</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/e$/</span>
1033 248:       <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/e$/</span>, <span class="ruby-value str">''</span>)
1034 249:     <span class="ruby-keyword kw">else</span>
1035 250:       <span class="ruby-identifier">r1</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">porter2_r1</span>
1036 251:       <span class="ruby-keyword kw">if</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/e$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-identifier">r1</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp re">/e$/</span> <span class="ruby-keyword kw">and</span> <span class="ruby-keyword kw">not</span> <span class="ruby-keyword kw">self</span> <span class="ruby-operator">=~</span> <span class="ruby-node">/#{Porter2::SHORT_SYLLABLE}e$/</span>
1037 252:         <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">sub</span>(<span class="ruby-regexp re">/e$/</span>, <span class="ruby-value str">''</span>)
1038 253:       <span class="ruby-keyword kw">else</span>
1039 254:         <span class="ruby-keyword kw">self</span>
1040 255:       <span class="ruby-keyword kw">end</span>
1041 256:     <span class="ruby-keyword kw">end</span>
1042 257:   <span class="ruby-keyword kw">end</span></pre>
1043                                         </div>
1044
1045                                 </div>
1046
1047
1048
1049
1050                         </div>
1051
1052
1053                         <div id="porter-tidy-method" class="method-detail ">
1054                                 <a name="method-i-porter2_tidy"></a>
1055
1056                                 <div class="method-heading">
1057
1058                                         <span class="method-name">porter2_tidy</span><span
1059                                                 class="method-args">()</span>
1060                                         <span class="method-click-advice">click to toggle source</span>
1061
1062                                 </div>
1063
1064                                 <div class="method-description">
1065
1066                                         <p>
1067 Tidy up the word before we get down to the algorithm
1068 </p>
1069
1070
1071
1072                                         <div class="method-source-code"
1073                                                 id="porter-tidy-source">
1074 <pre>
1075     <span class="ruby-comment cmt"># File lib/porter2_implementation.rb, line 7</span>
1076  7:   <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">porter2_tidy</span>
1077  8:     <span class="ruby-identifier">preword</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">to_s</span>.<span class="ruby-identifier">strip</span>.<span class="ruby-identifier">downcase</span>
1078  9:
1079 10:     <span class="ruby-comment cmt"># map apostrophe-like characters to apostrophes</span>
1080 11:     <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">gsub!</span>(<span class="ruby-regexp re">/‘/</span>, <span class="ruby-value str">&quot;'&quot;</span>)
1081 12:     <span class="ruby-identifier">preword</span>.<span class="ruby-identifier">gsub!</span>(<span class="ruby-regexp re">/’/</span>, <span class="ruby-value str">&quot;'&quot;</span>)
1082 13:
1083 14:     <span class="ruby-identifier">preword</span>
1084 15:   <span class="ruby-keyword kw">end</span></pre>
1085                                         </div>
1086
1087                                 </div>
1088
1089
1090
1091
1092                         </div>
1093
1094
1095                         <div id="stem-method" class="method-detail method-alias">
1096                                 <a name="method-i-stem"></a>
1097
1098                                 <div class="method-heading">
1099
1100                                         <span class="method-name">stem</span><span
1101                                                 class="method-args">(gb_english = false)</span>
1102                                         <span class="method-click-advice">click to toggle source</span>
1103
1104                                 </div>
1105
1106                                 <div class="method-description">
1107
1108
1109
1110
1111
1112                                 </div>
1113
1114
1115
1116
1117                                 <div class="aliases">
1118           Alias for: <a href="String.html#method-i-porter2_stem">porter2_stem</a>
1119                                 </div>
1120
1121                         </div>
1122
1123
1124                 </div>
1125
1126
1127         </div>
1128
1129
1130         <div id="rdoc-debugging-section-dump" class="debugging-section">
1131
1132                 <p>Disabled; run with --debug to generate this.</p>
1133
1134         </div>
1135
1136         <div id="validator-badges">
1137                 <p><small><a href="http://validator.w3.org/check/referer">[Validate]</a></small></p>
1138                 <p><small>Generated with the <a href="http://deveiate.org/projects/Darkfish-Rdoc/">Darkfish
1139                         Rdoc Generator</a> 1.1.6</small>.</p>
1140         </div>
1141
1142 </body>
1143 </html>
1144