includes/parser/Preprocessor.php

   1 <?php
   2 /**
   3  * Interfaces for preprocessors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Parser
  22  */
  23
  24 /**
  25  * @ingroup Parser
  26  */
  27 interface Preprocessor {
  28         /**
  29          * Create a new preprocessor object based on an initialised Parser object
  30          *
  31          * @param Parser $parser
  32          */
  33         public function __construct( $parser );
  34
  35         /**
  36          * Create a new top-level frame for expansion of a page
  37          *
  38          * @return PPFrame
  39          */
  40         public function newFrame();
  41
  42         /**
  43          * Create a new custom frame for programmatic use of parameter replacement
  44          * as used in some extensions.
  45          *
  46          * @param array $args
  47          *
  48          * @return PPFrame
  49          */
  50         public function newCustomFrame( $args );
  51
  52         /**
  53          * Create a new custom node for programmatic use of parameter replacement
  54          * as used in some extensions.
  55          *
  56          * @param array $values
  57          */
  58         public function newPartNodeArray( $values );
  59
  60         /**
  61          * Preprocess text to a PPNode
  62          *
  63          * @param string $text
  64          * @param int $flags
  65          *
  66          * @return PPNode
  67          */
  68         public function preprocessToObj( $text, $flags = 0 );
  69 }
  70
  71 /**
  72  * @ingroup Parser
  73  */
  74 interface PPFrame {
  75         const NO_ARGS = 1;
  76         const NO_TEMPLATES = 2;
  77         const STRIP_COMMENTS = 4;
  78         const NO_IGNORE = 8;
  79         const RECOVER_COMMENTS = 16;
  80         const NO_TAGS = 32;
  81
  82         const RECOVER_ORIG = 59; // = 1|2|8|16|32 no constant expression support in PHP yet
  83
  84         /** This constant exists when $indexOffset is supported in newChild() */
  85         const SUPPORTS_INDEX_OFFSET = 1;
  86
  87         /**
  88          * Create a child frame
  89          *
  90          * @param array|bool $args
  91          * @param bool|Title $title
  92          * @param int $indexOffset A number subtracted from the index attributes of the arguments
  93          *
  94          * @return PPFrame
  95          */
  96         public function newChild( $args = false, $title = false, $indexOffset = 0 );
  97
  98         /**
  99          * Expand a document tree node, caching the result on its parent with the given key
 100          */
 101         public function cachedExpand( $key, $root, $flags = 0 );
 102
 103         /**
 104          * Expand a document tree node
 105          */
 106         public function expand( $root, $flags = 0 );
 107
 108         /**
 109          * Implode with flags for expand()
 110          */
 111         public function implodeWithFlags( $sep, $flags /*, ... */ );
 112
 113         /**
 114          * Implode with no flags specified
 115          */
 116         public function implode( $sep /*, ... */ );
 117
 118         /**
 119          * Makes an object that, when expand()ed, will be the same as one obtained
 120          * with implode()
 121          */
 122         public function virtualImplode( $sep /*, ... */ );
 123
 124         /**
 125          * Virtual implode with brackets
 126          */
 127         public function virtualBracketedImplode( $start, $sep, $end /*, ... */ );
 128
 129         /**
 130          * Returns true if there are no arguments in this frame
 131          *
 132          * @return bool
 133          */
 134         public function isEmpty();
 135
 136         /**
 137          * Returns all arguments of this frame
 138          */
 139         public function getArguments();
 140
 141         /**
 142          * Returns all numbered arguments of this frame
 143          */
 144         public function getNumberedArguments();
 145
 146         /**
 147          * Returns all named arguments of this frame
 148          */
 149         public function getNamedArguments();
 150
 151         /**
 152          * Get an argument to this frame by name
 153          */
 154         public function getArgument( $name );
 155
 156         /**
 157          * Returns true if the infinite loop check is OK, false if a loop is detected
 158          *
 159          * @param Title $title
 160          * @return bool
 161          */
 162         public function loopCheck( $title );
 163
 164         /**
 165          * Return true if the frame is a template frame
 166          */
 167         public function isTemplate();
 168
 169         /**
 170          * Set the "volatile" flag.
 171          *
 172          * Note that this is somewhat of a "hack" in order to make extensions
 173          * with side effects (such as Cite) work with the PHP parser. New
 174          * extensions should be written in a way that they do not need this
 175          * function, because other parsers (such as Parsoid) are not guaranteed
 176          * to respect it, and it may be removed in the future.
 177          *
 178          * @param bool $flag
 179          */
 180         public function setVolatile( $flag = true );
 181
 182         /**
 183          * Get the "volatile" flag.
 184          *
 185          * Callers should avoid caching the result of an expansion if it has the
 186          * volatile flag set.
 187          *
 188          * @see self::setVolatile()
 189          * @return bool
 190          */
 191         public function isVolatile();
 192
 193         /**
 194          * Get the TTL of the frame's output.
 195          *
 196          * This is the maximum amount of time, in seconds, that this frame's
 197          * output should be cached for. A value of null indicates that no
 198          * maximum has been specified.
 199          *
 200          * Note that this TTL only applies to caching frames as parts of pages.
 201          * It is not relevant to caching the entire rendered output of a page.
 202          *
 203          * @return int|null
 204          */
 205         public function getTTL();
 206
 207         /**
 208          * Set the TTL of the output of this frame and all of its ancestors.
 209          * Has no effect if the new TTL is greater than the one already set.
 210          * Note that it is the caller's responsibility to change the cache
 211          * expiry of the page as a whole, if such behavior is desired.
 212          *
 213          * @see self::getTTL()
 214          * @param int $ttl
 215          */
 216         public function setTTL( $ttl );
 217
 218         /**
 219          * Get a title of frame
 220          *
 221          * @return Title
 222          */
 223         public function getTitle();
 224 }
 225
 226 /**
 227  * There are three types of nodes:
 228  *     * Tree nodes, which have a name and contain other nodes as children
 229  *     * Array nodes, which also contain other nodes but aren't considered part of a tree
 230  *     * Leaf nodes, which contain the actual data
 231  *
 232  * This interface provides access to the tree structure and to the contents of array nodes,
 233  * but it does not provide access to the internal structure of leaf nodes. Access to leaf
 234  * data is provided via two means:
 235  *     * PPFrame::expand(), which provides expanded text
 236  *     * The PPNode::split*() functions, which provide metadata about certain types of tree node
 237  * @ingroup Parser
 238  */
 239 interface PPNode {
 240         /**
 241          * Get an array-type node containing the children of this node.
 242          * Returns false if this is not a tree node.
 243          */
 244         public function getChildren();
 245
 246         /**
 247          * Get the first child of a tree node. False if there isn't one.
 248          *
 249          * @return PPNode
 250          */
 251         public function getFirstChild();
 252
 253         /**
 254          * Get the next sibling of any node. False if there isn't one
 255          */
 256         public function getNextSibling();
 257
 258         /**
 259          * Get all children of this tree node which have a given name.
 260          * Returns an array-type node, or false if this is not a tree node.
 261          */
 262         public function getChildrenOfType( $type );
 263
 264         /**
 265          * Returns the length of the array, or false if this is not an array-type node
 266          */
 267         public function getLength();
 268
 269         /**
 270          * Returns an item of an array-type node
 271          */
 272         public function item( $i );
 273
 274         /**
 275          * Get the name of this node. The following names are defined here:
 276          *
 277          *    h             A heading node.
 278          *    template      A double-brace node.
 279          *    tplarg        A triple-brace node.
 280          *    title         The first argument to a template or tplarg node.
 281          *    part          Subsequent arguments to a template or tplarg node.
 282          *    #nodelist     An array-type node
 283          *
 284          * The subclass may define various other names for tree and leaf nodes.
 285          */
 286         public function getName();
 287
 288         /**
 289          * Split a "<part>" node into an associative array containing:
 290          *    name          PPNode name
 291          *    index         String index
 292          *    value         PPNode value
 293          */
 294         public function splitArg();
 295
 296         /**
 297          * Split an "<ext>" node into an associative array containing name, attr, inner and close
 298          * All values in the resulting array are PPNodes. Inner and close are optional.
 299          */
 300         public function splitExt();
 301
 302         /**
 303          * Split an "<h>" node
 304          */
 305         public function splitHeading();
 306 }