doctrine

What is doctrine?

The doctrine npm package is a JSDoc type expression parser written in JavaScript. It allows developers to parse JSDoc comments and extract useful information and metadata about the code, which can be used for documentation generation, type checking, and other analysis purposes.

What are doctrine's main functionalities?

Parsing JSDoc comments

This feature allows you to parse JSDoc comments to extract information such as descriptions, parameters, and return types. The 'unwrap' option tells doctrine to strip the leading /**, trailing */, and any * that begins a line from the source text.

{"var doctrine = require('doctrine');\nvar ast = doctrine.parse('/**\n * This function adds two numbers together.\n * @param {number} a The first number.\n * @param {number} b The second number.\n * @return {number} The sum of the two numbers.\n */', { unwrap: true });\nconsole.log(ast);"}

Extracting type information

With this feature, you can extract type information from JSDoc comments. It parses the type expression and provides an abstract syntax tree (AST) representing the type information.

{"var doctrine = require('doctrine');\nvar ast = doctrine.parse('/** @type {Array.<string>} */', { unwrap: true });\nconsole.log(ast);"}

Parsing with recoverable errors

This feature allows parsing with recoverable errors, meaning that it will try to parse as much as possible without throwing an error immediately. This is useful for handling incomplete or incorrect JSDoc comments.

{"var doctrine = require('doctrine');\ntry {\n  var ast = doctrine.parse('/** @param {string} name */', { recoverable: true });\n  console.log(ast);\n} catch (error) {\n  console.error('Failed to parse:', error);\n}"}

Other packages similar to doctrine

comment-parser

The comment-parser package is another JSDoc comment parsing library. It focuses on extracting tags and descriptions from comments. Compared to doctrine, comment-parser may offer a different API and parsing strategy, potentially making it more suitable for certain use cases.

jsdoctypeparser

jsdoctypeparser is a parser for JSDoc type expressions. It is similar to doctrine in that it can parse type information from JSDoc comments, but it might have different parsing capabilities or API design, which could make it preferable depending on the developer's needs.

esdoc

esdoc is a documentation generator that parses JSDoc comments, but it also includes a full suite of features for generating comprehensive documentation for JavaScript code. While doctrine focuses solely on parsing, esdoc provides an end-to-end solution for documentation.

README

doctrine (doctrine) is JSDoc parser.

It is now used by content assist system of Eclipse Orion (detail). And used as JSDoc validator in ESLint.

Doctrine can be used in a web browser with using browserify. or in a Node.js application via the package manager:

npm install doctrine

simple example:

doctrine.parse(
    [
        "/**",
        " * This function comment is parsed by doctrine",
        " * @param {{ok:String}} userName",
        "*/"
    ].join('\n'), { unwrap: true });

and gets following information

{
    "description": "This function comment is parsed by doctrine",
    "tags": [
        {
            "title": "param",
            "description": null,
            "type": {
                "type": "RecordType",
                "fields": [
                    {
                        "type": "FieldType",
                        "key": "ok",
                        "value": {
                            "type": "NameExpression",
                            "name": "String"
                        }
                    }
                ]
            },
            "name": "userName"
        }
    ]
}

see demo page more detail.

Options

doctrine.parse

We can pass options to doctrine.parse(comment, options).

{
    unwrap: boolean,          // default: false
    tags: [ string ] | null,  // default: null
    recoverable: boolean,     // default: false
    sloppy: boolean,          // default: false
    lineNumbers: boolean      // default: false
}

unwrap

When unwrap is true, doctrine attempt to unwrap comment specific string from a provided comment text. (removes /**, */ and *) For example, unwrap transforms

/**
 * @param use
 */

to

@param use

If a provided comment has these comment specific strings, you need to specify this unwrap option to true.

tags

When tags array is specified, doctrine only produce tags that is specified in this array. For example, if you specify [ 'param' ], doctrine only produces param tags. If null is specified, doctrine produces all tags that doctrine can recognize.

recoverable

When recoverable is true, doctrine becomes recoverable - When failing to parse jsdoc comment, doctrine recovers its state and attempt to continue parsing.

sloppy

When sloppy is true,

@param String [foo]

's [foo] is interpreted as a optional parameter, not interpreted as a name of this @param.

lineNumbers

When lineNumbers is true, parsed tags will include a lineNumber property indicating the line (relative to the start of the comment block) where each tag is located in the source. So, given the following comment:

/**
 * @param {String} foo
 * @return {number}
 */

The @param tag will have lineNumber: 1, and the @return tag will have lineNumber: 2.

License

doctrine

Copyright (C) 2012 Yusuke Suzuki (twitter: @Constellation) and other contributors.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

esprima

some of functions is derived from esprima

Copyright (C) 2012, 2011 Ariya Hidayat (twitter: @ariyahidayat) and other contributors.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

closure-compiler

some of extensions is derived from closure-compiler

Apache License Version 2.0, January 2004 http://www.apache.org/licenses/