The tokenizer functions provide an interface to the
PHP tokenizer embedded in the Zend Engine. Using these
functions you may write your own PHP source analyzing
or modification tools without having to deal with the
language specification at the lexical level.
See also the appendix about tokens.
No external libraries are needed to build this extension.
Beginning with PHP 4.3.0 these functions are enabled by default.
For older versions you have to configure and compile PHP with
--enable-tokenizer. You can disable
tokenizer support with --disable-tokenizer.
The windows version of PHP has built in
support for this extension. You do not need to load any additional
extension in order to use these functions.
Note:
Builtin support for tokenizer is available with PHP 4.3.0.
When the extension has either been compiled into PHP or dynamically loaded
at runtime, the tokens listed in Appendix Q are defined as
constants.
Here is a simple example PHP scripts using the tokenizer that
will read in a PHP file, strip all comments from the source
and print the pure code only.
Example 1. Strip comments with the tokenizer <?php
/*
* T_ML_COMMENT does not exist in PHP 5.
* The following three lines define it in order to
* preserve backwards compatibility.
*
* The next two lines define the PHP 5 only T_DOC_COMMENT,
* which we will mask as T_ML_COMMENT for PHP 4.
*/
if (!defined('T_ML_COMMENT')) {
define('T_ML_COMMENT', T_COMMENT);
} else {
define('T_DOC_COMMENT', T_ML_COMMENT);
}
$source = file_get_contents('example.php');
$tokens = token_get_all($source);
foreach ($tokens as $token) {
if (is_string($token)) {
// simple 1-character token
echo $token;
} else {
// token array
list($id, $text) = $token;
switch ($id) {
case T_COMMENT:
case T_ML_COMMENT: // we've defined this
case T_DOC_COMMENT: // and this
// no action on comments
break;
default:
// anything else -> output "as is"
echo $text;
break;
}
}
}
?> |
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