X-Git-Url: http://www.aleph1.co.uk/gitweb/?a=blobdiff_plain;ds=sidebyside;f=vendor%2Fnikic%2Fphp-parser%2Fdoc%2Fcomponent%2FPretty_printing.markdown;fp=vendor%2Fnikic%2Fphp-parser%2Fdoc%2Fcomponent%2FPretty_printing.markdown;h=d6198e315f098635e87ca2bad7687b30e7168303;hb=af6d1fb995500ae68849458ee10d66abbdcfb252;hp=0000000000000000000000000000000000000000;hpb=680c79a86e3ed402f263faeac92e89fb6d9edcc0;p=yaffs-website diff --git a/vendor/nikic/php-parser/doc/component/Pretty_printing.markdown b/vendor/nikic/php-parser/doc/component/Pretty_printing.markdown new file mode 100644 index 000000000..d6198e315 --- /dev/null +++ b/vendor/nikic/php-parser/doc/component/Pretty_printing.markdown @@ -0,0 +1,96 @@ +Pretty printing +=============== + +Pretty printing is the process of converting a syntax tree back to PHP code. In its basic mode of +operation the pretty printer provided by this library will print the AST using a certain predefined +code style and will discard (nearly) all formatting of the original code. Because programmers tend +to be rather picky about their code formatting, this mode of operation is not very suitable for +refactoring code, but can be used for automatically generated code, which is usually only read for +debugging purposes. + +Basic usage +----------- + +```php +$stmts = $parser->parse($code); + +// MODIFY $stmts here + +$prettyPrinter = new PhpParser\PrettyPrinter\Standard; +$newCode = $prettyPrinter->prettyPrintFile($stmts); +``` + +The pretty printer has three basic printing methods: `prettyPrint()`, `prettyPrintFile()` and +`prettyPrintExpr()`. The one that is most commonly useful is `prettyPrintFile()`, which takes an +array of statements and produces a full PHP file, including opening ` **Note:** This functionality is **experimental** and not yet complete. + +For automated code refactoring, migration and similar, you will usually only want to modify a small +portion of the code and leave the remainder alone. The basic pretty printer is not suitable for +this, because it will also reformat parts of the code which have not been modified. + +Since PHP-Parser 4.0, an experimental formatting-preserving pretty-printing mode is available, which +attempts to preserve the formatting of code (those AST nodes that have not changed) and only reformat +code which has been modified or newly inserted. + +Use of the formatting-preservation functionality requires some additional preparatory steps: + +```php +use PhpParser\{Lexer, NodeTraverser, NodeVisitor, Parser, PrettyPrinter}; + +$lexer = new Lexer\Emulative([ + 'usedAttributes' => [ + 'comments', + 'startLine', 'endLine', + 'startTokenPos', 'endTokenPos', + ], +]); +$parser = new Parser\Php7($lexer); + +$traverser = new NodeTraverser(); +$traverser->addVisitor(new NodeVisitor\CloningVisitor()); + +$printer = new PrettyPrinter\Standard(); + +$oldStmts = $parser->parse($code); +$oldTokens = $lexer->getTokens(); + +$newStmts = $traverser->traverse($oldStmts); + +// MODIFY $newStmts HERE + +$newCode = $printer->printFormatPreserving($newStmts, $oldStmts, $oldTokens); +``` + +If you make use of the name resolution functionality, you will likely want to disable the +`replaceNodes` option. This will add resolved names as attributes, instead of directlying modifying +the AST and causing spurious changes to the pretty printed code. For more information, see the +[name resolution documentation](Name_resolution.markdown). + +This functionality is experimental and not yet fully implemented. It should not provide incorrect +code, but it may sometimes reformat more code than necessary. Open issues are tracked in +[issue #344](https://github.com/nikic/PHP-Parser/issues/344). If you encounter problems while using +this functionality, please open an issue, so we know what to prioritize.