---
title: Library Metadata - Boost C++ Libraries
copyright: Beman Dawes, David Abrahams, 1998-2005. Rene Rivera 2004-2005.
revised: 2005-12-17 14:32:46 -0500
---


Library Metadata - Boost C++ Libraries



Library Metadata
================

A module can contain an optional file which describes the
 libraries that it contains. This is located at
 `meta/libraries.json`. It either contains a single
 json object for a single library, or a list or json objects for
 any number of libraries.


For example, for a single library:
```

{
    "key": "unordered",
    "name": "Unordered",
    "authors": [ "Daniel James" ],
    "maintainers": [ "Daniel James <dnljms -at- gmail.com>" ],
    "description": "Unordered associative containers.",
    "category": [
        "Containers"
    ]
}


```

An example for multiple libraries:
```

[
    {
        "key": "functional",
        "name": "Functional",
        "authors": [ "Mark Rodgers" ],
        "description": "The Boost.Function library contains a family of class templates that are function object wrappers.",
        "category": [
            "Function-objects"
        ]
    },
    {
        "key": "functional/factory",
        "name": "Functional/Factory",
        "authors": [ "Tobias Schwinger" ],
        "maintainers": [ "Tobias Schwinger <tschwinger -at- isonews2.com>" ],
        "description": "Function object templates for dynamic and static object creation",
        "documentation": "factory/",
        "category": [
            "Function-objects"
        ]
    },
]


```

Json fields
-----------


### key


This is a unique identifier for the library, typically the
 path to it from the `libs` directory.


### name


Human readable name of the library


### status


Used for libraries with special statuses, currently can have
 value `deprecated` for deprecated libraries, and
 `hidden` for libraries which shouldn't be displayed to
 the user.


### authors


Either a string, or a list of strings, containing the names
 of the authors


### description


A brief description of what the library does


### category


A list of categories that the library belongs to, the full
 list is below.


### documentation


Path to the documentation, defaults to the root of the
 module.


### cxxstd


The minimum C++ standard compilation level at which
 all, or the large majority, of the functionality in
 the library is usable. The possible values are: 


* 98 = C++98
* 03 = C++98/C++03
* 11 = C++11
* 14 = C++14
* 17 = C++17
* 20 = C++20


The level only indicates the minimum level, which
 means that the functionality of the library can be
 used when compiling at that level or at a higher
 level. There may be some functionality in the library
 which will need a higher C++ standard compilation
 level than is indicated by this value, but the
 information about that specific functionality will be
 provided for the end-user within the documentation for
 that library. If a library does not have this field it
 indicates that the end-user will have to read the
 library documentation to understand what C++ standard
 compilation level is needed to use the library. 


Available categories
--------------------
String
String and text processing
Containers
Containers
Iterators
Iterators
Algorithms
Algorithms
Function-objects
Function objects and higher-order programming
Generic
Generic Programming
Metaprogramming
Template Metaprogramming
Preprocessor
Preprocessor Metaprogramming
Concurrent
Concurrent Programming
Math
Math and numerics
Correctness
Correctness and testing
Error-handling
Error handling and recovery
Data
Data structures
Domain
Domain Specific
Image-processing
Image processing
IO
Input/Output
Inter-language
Inter-language support
Emulation
Language Features Emulation
Memory
Memory
Parsing
Parsing
Patterns
Patterns and Idioms
Programming
Programming Interfaces
State
State Machines
System
System
Miscellaneous
Miscellaneous
workarounds
Broken compiler workarounds