comparison vendor/nikic/php-parser/UPGRADE-2.0.md @ 0:c75dbcec494b

Initial commit from drush-created site

+Upgrading from PHP-Parser 1.x to 2.0
+====================================
+
+### PHP version requirements
+
+PHP-Parser now requires PHP 5.4 or newer to run. It is however still possible to *parse* PHP 5.2 and
+PHP 5.3 source code, while running on a newer version.
+
+### Creating a parser instance
+
+Parser instances should now be created through the `ParserFactory`. Old direct instantiation code
+will not work, because the parser class was renamed.
+
+Old:
+
+```php
+use PhpParser\Parser, PhpParser\Lexer;
+$parser = new Parser(new Lexer\Emulative);
+```
+
+New:
+
+```php
+use PhpParser\ParserFactory;
+$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+```
+
+The first argument to `ParserFactory` determines how different PHP versions are handled. The
+possible values are:
+
+ * `ParserFactory::PREFER_PHP7`: Try to parse code as PHP 7. If this fails, try to parse it as PHP 5.
+ * `ParserFactory::PREFER_PHP5`: Try to parse code as PHP 5. If this fails, try to parse it as PHP 7.
+ * `ParserFactory::ONLY_PHP7`: Parse code as PHP 7.
+ * `ParserFactory::ONLY_PHP5`: Parse code as PHP 5.
+
+For most practical purposes the difference between `PREFER_PHP7` and `PREFER_PHP5` is mainly whether
+a scalar type hint like `string` will be stored as `'string'` (PHP 7) or as `new Name('string')`
+(PHP 5).
+
+To use a custom lexer, pass it as the second argument to the `create()` method:
+
+```php
+use PhpParser\ParserFactory;
+$lexer = new MyLexer;
+$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7, $lexer);
+```
+
+### Rename of the `PhpParser\Parser` class
+
+`PhpParser\Parser` is now an interface, which is implemented by `Parser\Php5`, `Parser\Php7` and
+`Parser\Multiple`. Parser tokens are now defined in `Parser\Tokens`. If you use the `ParserFactory`
+described above to create your parser instance, these changes should have no further impact on you.
+
+### Removal of legacy aliases
+
+All legacy aliases for classes have been removed. This includes the old non-namespaced `PHPParser_`
+classes, as well as the classes that had to be renamed for PHP 7 support.
+
+### Deprecations
+
+The `set()`, `setFirst()`, `append()` and `prepend()` methods of the `Node\Name` class have been
+deprecated. Instead `Name::concat()` and `Name->slice()` should be used.
+
+### Miscellaneous
+
+* The `NodeTraverser` no longer clones nodes by default. If you want to restore the old behavior,
+  pass `true` to the constructor.
+* The legacy node format has been removed. If you use custom nodes, they are now expected to
+  implement a `getSubNodeNames()` method.
+* The default value for `Scalar` node constructors was removed. This means that something like
+  `new LNumber()` should be replaced by `new LNumber(0)`.
+* String parts of encapsed strings are now represented using `Scalar\EncapsStringPart` nodes, while
+  previously raw strings were used. This affects the `parts` child of `Scalar\Encaps` and
+  `Expr\ShellExec`.