An attempt to catalogue and curate Cat's Eye Technologies [Freely redistributable*]
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Chrysoberyl is an attempt to catalogue, and curate, the things produced by, and related to, Cat's Eye Technologies.

It is something between a wiki and a database and a semantic web and The Devil's Dictionary.

It is supposed to be primarily informative, and only secondarily machine- processable, and only thirdly structured. So, the schemas in use are fuzzy, flexible, incomplete, and subject to change and the drop of a hat.

It does not contain only those things produced by Cat's Eye Technologies; in theory, anything can be in it. In these cases, the entry may consist simply of commentary on the item, or a short explanation of how it relates to Cat's Eye Technologies.

General Format

The Chrysoberyl data files are in YAML format, in the data directory.

The division into files is artificial; files make no semantic difference; if they were all concatenated into a single file, the data would be the same.

Each top-level key in the data is the name of a node. The name should be both human and machine readable, like the name of a page in a wiki.

To disambiguate nodes which would otherwise have the same name, a disambiguating phrase may be placed after the name in parentheses.

Each node must have a type field, whose value names a node whose type field is type. (This necessitates the presence of a node named type whose type is type.)

Each node may have any of the following fields:

  • summary -- a one-line summary of the node
  • description -- a relatively objective description of the node
  • commentary -- a subjective opinion, by Chris Pressey, of the node
  • subtitle -- expanding on the name of the node
  • acronym-for -- expanding the name of the node
  • hidden -- if true, does not show up in related() lists
  • ...

Each node can have a domain, which influences how breadcrumbs are arranged. For example, domain of lingography is Chris Pressey. Domain of everything which does not specify a domain is Cat's Eye Technologies. (This scheme is, of course, subject to modifications)

In addition, nodes of particular types may have fields that have meaning for that type.

Specific Schema

In the following, an "implementable" (for lack of a better term) is pretty much anything that can be implemented. Specifically, it refers to any of the following:

  • a programming language (which includes machine languages)
  • a game
  • a platform (which includes operating systems, architectures, and frameworks)
  • a tool
  • a library
  • a musical composition

An implementable may have zero or more implementations.

Ideally (it is not really this way in Chrysoberyl yet), an implementation could be either an "actual" implementation, or a specification document which attempts to unambiguously describe how to implement the implementable (for example, a language specification would be an "implementation" of a programming language, and a musical score would be an "implementation" of a musical composition.)

Each implementation may or may not be a reference implementation. Ideally, Chrysoberyl should understand that an implementable can have more than one reference implementation. (For example, having a prescriptive specification and a reference implementation can be useful.)

A standards body could also be a reference implementation, in a sense, as it can act as a disambiguator for when reference implementations prove to be insufficiently clear. (Maybe this is stretching it?)

Each implementation may be included in zero or more distributions.

The reference distribution of an implementable is defined as the first distribution that the first reference implementation is included in. (This derived notion of reference distribution should replace the explicit notion of a reference distribution currently present in Chrysoberyl.)

Only one distribution can be the reference distribution for an implementable. There can be only one reference distribution for an implementable. Typically It will contain the spec and/or reference implementation of the implementable.

If there is no reference distribution, a link to its specification (even if it's just a page on a wiki) or standards body (even if it's just "the official website") is required.

(This part needs updating) Therefore, every implementable needs at least one of the following:

  • defining-distribution (a key)
  • specification-link (a URL, or esowiki)
  • standards-body (a URL)
  • no-specification: true

defining-distribution is really just a stopgap measure that basically means "defined by the specification that you will find somewhere in this distribution" -- really the spec itself should be referenced in the node.

If none of the last three of that list are present, we expect an implementable to have a reference-distribution. If that key is not present, we look for a distribution called FOO distribution where FOO is the name of the implementable.

An implementable may also have multiple implementations. Each implementation may be in zero or more distributions, and a distribution may contain multiple implementations. Only one implementation can be the reference implementation for an implementable.

An implementation may be an implementation of multiple implementables. (For example, gcc is an implementation of ANSI C and C99.)

If an implementation does not give authors, they are assumed to be the authors of the implementable it implements. Ditto auspices.

A distribution has releases and, often, can be checked out of some version control system, and, often, has a place to report bugs. An implementation, by itself, has none of those things (at least not in a structured way -- it might simply be a page on a wiki somewhere.) The releases of a distribution should be sorted from earliest to latest.

On the other hand, neither distributions nor implementables have licenses, but implementations do. The license of a distribution can be inferred from the licenses of the implementations contained with it.

Each implementation has an implementation-type. For a programming language, this may be interpreter, compiler, etc. For a platform, this currently must be "emulator" (even if the platform is a framework...)

An implementation may claim that it is prebuilt in its distribution. This assumes it's only in one distribution. Really, being prebuilt somewhere is a property of the distribution, but this fudging makes some things easier for now.

Each platform must specify what its native language is. Implementations may specify, along with a host language, a host platform.

Every implementable must have a development stage. The development stage of an implementation, if not given, is assumed to be on par with the development stage of the thing it implements. Distributions never have development stages, as they are, in a sense, always works in progress.

side note

Any tool which understands a language may be considered an implementation of that language: an interpreter, a compiler, a parser, a static analyzer, a pretty-printer, etc., are all implementations.

This is actually kind of weird (e.g. yucca is an implementation of BASIC? maybe say "partial implementation" in the template if the implementation type is not interpreter or compiler) but we'll go with it for now.


See the file LICENSE.


chrysoberyl is a Python script included in this distribution which can process the Chrysberyl database. It is located in the bin directory, and its source modules are in the src/chrysoberyl directory. Things it can do include:

  • check the data for consistency (all subcommands do this)
  • render Jinja2 templates with the data (one file per node) and dump all nodes to a single JSON file (chrysoberyl render)
  • render all nodes to a JSON blob (chrysoberyl jsonify)
  • write out an Atom news feed (chrysoberyl announce)

Less common activities include:

  • create a toolshelf catalogue of Bitbucket repos (chrysoberyl catalogue)
  • write out a mapping between nodes and distributions (chrysoberyl mkdistmap)

The tool has the following requirements, which can be installed with toolshelf or easy_install or pip or whatever: