Today, after two years and a half of (irregular) development, and 465 commits, I have released the first beta version of Declt 4.0, my reference manual generator for Common Lisp libraries.

I seldom release official beta versions of software, let alone make announcements about them, but this one deserves an exception. Since version 3, Declt has been undergoing a massive, SOC-oriented, overhaul. The intent is to reimplement it into a clean 3-stages pipeline. Stage one, the "assessment" stage is in charge of gathering information. Stage two, the "assembly" stage, creates a documentation template specifying how the information is to be organized. Finally, Stage three, the "typesetting" stage, renders the template in a specific output format. Of course, the purpose is to eventually be able to support different kinds of templates and output formats.

Declt 4.0b1 marks the achievement of Stage one, which is now complete. It also contains a lot of new (and long awaited) features and improvements. The user manual has been updated to provide an overview of the new architecture, along with some details about Stage one of the pipeline. From now on, I'm also going to release new versions of Quickref to closely follow the evolution of Declt.

Apart from the aforementioned architecture overhaul, which really boils down to internals shaking and shouldn't affect the end-user much, a lot of new features and improvements are also provided in this release. They are listed below.

Backward Incompatible Changes

For the benefit of Separation of Concerns, but also for other reasons, a number of keyword arguments to the declt function have been renamed. :hyperlinks becomes :locations, :version becomes :library-version, :texi-directory becomes :output-directory, and :texi-name becomes :file-name.

New Features

Default / Standard Values

Declt now has the ability to advertise or hide properties that get default / standard values (e.g. standard method combination, :instance slot allocation, etc.).

Support for Aliases

Declt now recognizes and advertises "aliases", that is, funcoids which have their fdefinition, macro, or compiler macro function set manually to another, original, definition.

Support for New Programmatic Entities

Typed structures and setf compiler macros are now properly detected and documented with all the specific information.

Proper Support for Uninterened Symbols

Such symbols may be encountered on several occasions such as slot names (trivialib, for example, defines structures with uninterned slot names in order to prevent access to them). Definitions named with uninterned symbols are considered private, and denoted by the empty set package (∅).

SBCL 2.1.2 Required

The following enhancements depend on it:

• short form setf expanders now get correct source information,
• method combinations lambda-lists are now documented.

Domestic vs. Foreign Definitions

The concept of domestic (as opposed to foreign) definition has been extended to include those created in one of the sources files of the library being documented, even if the symbol naming the definition is from a foreign package. If the source file is unknown, then the symbol's package must be domestic. The general intent is to consider language extensions as domestic, hence, always documented. For example, a new method on a standard generic function (say, initialize-instance) will now always appear in the documentation.

This refinement is accompanied by a new option allowing to include foreign definitions in the generated documentation. Of course, only foreign definitions somehow related to the library being documented will appear in the documentation. Also, those definitions will in general be partial: only the parts relevant to the library being documented will appear. Continuing with the initialize-instance example, new methods normally appear as toplevel, standalone definitions in the documentation (and their parent generic function is simply mentioned). If foreign definitions are included however, there will be a toplevel entry for the generic function, and all methods defined in the library will be documented there (truly foreign methods won't appear at all).

Introspection Heuristic

Until now, there was a single heuristic for finding domestic definitions, which was to start from domestic packages and scan as many connections between symbols as possible. That heuristic is reasonably fast, but may occasionally miss some domestic definitions. Declt now has the ability to scan all symbols in the Lisp image instead of only the ones from domestic packages. This new option ensures that all domestic definitions are found, at the expense of a much greater computation time.

Supported Licenses

The Microsoft Public License has been added.

Info Installation Category

In other words, the value of Texinfo's @direntry command is now customizable (instead to being hardwired to "Common Lisp").

Improvements

Documentation Thinning

Packages reference lists do not point to methods directly anymore (as they can be reached via the generic function's reference). Also, only slots for which the parent classoid is named from another package are now referenced.

Files reference lists do not point to slots anymore (as they can be reached via the parent classoid's reference). Also, only methods for which the parent generic function is defined in another file are now referenced.

The readability of long references has been improved. In particular, they don't advertise the type of the referenced definitions anymore, when there is no ambiguity.

Slot documentation now advertises the slot name's package only when different from that of the parent classoid.

Non standalone method documentation now advertises the source file only when different from that of the parent generic function.

The rendering of EQL specializers has been inmproved.

The documentation of setf / writer methods doesn't render the "new value" argument / specializer anymore.

Merging

Generic definitions containing only reader / writer methods are upgraded to specific reader / writer categories, and definition merging is now only attempted on those.

Lambda Lists

Uninformative parts of lambda lists are now filtered out. This includes &whole, &environment, &aux variables, along with options / keyword variables and default values.

Method specializers in lambda lists now link back to their respective class definitions.

Method Combinations

The method combination discovery scheme has been upgraded to benefit from SBCL 1.4.8's enhancements (themselves following my ELS 2018 paper). The old code didn't break, but prevented unused method combinations from being detected.

Bug Fixes and Workarounds

ASDF

Better handling of missing / unloaded components or dependencies (this can happen for instance with feature-dependent conditional inclusion).

Cope with the lack of specification of the license information in ASDF systems by coercing to a string.

Fix several cases of system files documentation duplication. Declt automatically documents .asd files as special cases of Lisp files. However, some systems have the bad (IMHO) habit of mentioning them explicitly as components (e.g. static files). When this happens, Declt silently discards that definition and keeps its own (at the expense of having a slightly incorrect system documentation).

Anchoring

After years of vain attempts at providing human-readable yet unique anchor names (which was only really useful for Info, BTW), I finally got rid of my last bit of idealism. Anchor names now use numerical definition UIDs, and since Texinfo allows me to expand references with some more information than just the anchor, it's good enough. Besides, it fixes the last remaining rare cases exhibiting the fact that it's just impossible to have anchors that are both human-readable and unique.

Setf Expanders

Fix the computation of short form setf epxander lambda lists (which didn't correctly handle the presence of optional or rest arguments before.

Handle the potential unavailability of a setf expander's update function or short form operator. Document it if applicable. Also signal a warning when the expander is domestic.

Following up with the latest release of Declt, I'm also happy to announce the release of Quickref 3.0 "The Alchemist", our reference manuals aggregator for Quicklisp libraries. The official website has been updated yesterday with both the latest Quicklisp version, and the new Declt, resulting in the documentation of 1792 Common Lisp libraries.

Surfing on the energizing wave of ELS 2019, the 12 European Lisp Symposium, I'm happy to announce the release of Quickref 2.0, codename "Be Quick or Be Dead".

The major improvement in this release, justifying an increment of the major version number (and the very appropriate codename), is the introduction of parallel algorithms for building the documentation. I presented this work last week in Genova so I won't go into the gory details here, but for the brave and impatient, let me just say that using the parallel implementation is just a matter of calling the BUILD function with :parallel t :declt-threads x :makeinfo-threads y (adjust x and y as you see fit, depending on your architecture).

The second featured improvement is the introduction of an author index, in addition to the original one. The author index is still a bit shaky, mostly due to technical problems (calling asdf:find-system almost two thousand times simply doesn't work) and also to the very creative use that some library authors have of the ASDF author and maintainer slots in the system descriptions. It does, however, a quite decent job for the majority of the authors and their libraries'reference manuals.

Finally, the repository now has a fully functional continuous integration infrastructure, which means that there shouldn't be anymore lags between new Quicklisp (or Quickref) releases and new versions of the documentation website.

Thanks to Antoine Hacquard, Antoine Martin, and Erik Huelsmann for their contribution to this release! A lot of new features are already in the pipe. Currently documenting 1720 libraries, and counting...

Here is a flagrant illustration of the robustness principle, or rather, of a failure to honor it.

I was investigating a bug in Declt where some floating point numbers were printed with exponent markers (e.g. 0.5f0 instead of just 0.5) in the Texinfo file, which broke the parsing of the file by Perl.

Eventually, I found out a double infringement of the robustness principle. First of all, Declt failed to comply with part 1 of the robustness principle: be lenient with the others. The Texinfo file generation routine should have been wrapped into a call to WITH-STANDARD-IO-SYNTAX and it wasn't. Always do that to be on the safe side. Lesson learnt.

This failure on my part, however, had the interesting consequence of exhibiting what I consider a serious infringement of part 2 of the robustness principle: be strict with yourself. It would have remained unnocited otherwise. The culprit here is not Declt. This time, it's the common-lisp-stat library. Problem: the simple fact of loading this library globally changes the value of *READ-DEFAULT-FLOAT-FORMAT* from SINGLE-FLOAT (the default) to DOUBLE-FLOAT. This is bad, and it can break your code in all sorts of nasty ways.

Explanation

*READ-DEFAULT-FLOAT-FORMAT* tells the reader how to read floats when no exponent marker is provided. By default, 0.5 will be read as a SINGLE-FLOAT. But this variable also influences the printer (out of a concern for printing readably I guess): when printing a float of a different format than the current default, then the appropriate exponent marker is also printed. So here is precisely what happened. Declt had been compiled with some floats (e.g. 0.5) read as SINGLE-FLOATs. Later on, those floats were supposed to be printed aesthetically as such. But right after loading common-lisp-stat, the default format changed to DOUBLE-FLOAT and all of a sudden 0.5 started to be printed as 0.5f0.

Consequences

This is bad enough already, but consider that messing with the standard IO syntax globally like this can break your code in all other sorts of even nastier ways. Imagine for instance that common-lisp-stat had been loaded before Declt, and Declt needed to be recompiled. All of a sudden, Declt would be using double floats and the bug would be gone. That is, until the next start of the REPL, after which all floats would be printed like 0.5d0!

So granted, my code wasn't robust enough. But please, don't mess with standard IO syntax globally!

I'm happy to announce the release of Declt 2.1 "Jonathan Archer".

New in this release:

• Handle recent change in SBCL's SB-INT:INFO API.
• Handle list of contacts (strings) in ASDF systems author and maintainer slots.
• Some backward-incompatible changes in the keyword arguments to the DECLT function.
• More hyperlinks between systems and source files.
• More robust system's packages collection (no more code walking).
• More robust handling of unavailable ASDF components.
• More robust naming of cross-references.

Find it at the usual place...

I've just released version 2.0 of ASDF-FLV, my ASDF extension for supporting file-local variables (ala *PACKAGE*). The code hasn't changed, but as for my other libraries, the system and package names are now prefixed with net.didierverna. ASDF-FLV is also available on GitHub now.

The reason I'm doing this now is that at least two of my other libraries are going to use it in a mandatory way, either directly or indirectly (and in turn, that's because no implementation has bothered to implement CDR #9 yet ;-).

Declt 2.0 "Kathryn Janeway" is out. This release doesn't contain any change in functionality, yet deserves a major version upgrade since it contains 3 important changes: an infrastructure revamp (along the lines of what Clon endured not so long ago), a license switch from the GNU GPL to a BSD one, and finally a system / package name change. The prefix is now net.didierverna instead of com.dvlsoft. Do I need to apologize for this again? :-)

Find it at the usual place...

After 15 betas, I'm happy enough with the current state of Declt to finally make a 1.0 release.

A lot of things have changed since the previous version, sometimes in a backward-incompatible way. Many more items are documented (including, as you have recently seen, method combinations). In addition to the reference manual, generated by Declt itself, there is now a real user manual.

Declt is still SBCL-only, requires ASDF 3 and Texinfo 4 but generates code that is compatible with Texinfo 5. Also, beware, I've deleted the old repository and moved the project to GitHub. Below is a more precise description of what Declt currently does.

Declt (pronounce "dec'let") is a reference manual generator for Common Lisp libraries. It works by loading an ASDF system and introspecting its contents. The generated documentation contains the description for the system itself and its components (modules and files), the packages defined in that system and the definitions found in those packages.

Exported and internal definitions are listed separately. This allows the reader to have a quick view on the library's public API. Within each section, definitions are sorted lexicographically.

In addition to ASDF system components and packages, Declt documents the following definitions: constants, special variables, symbol macros, macros, setf expanders, compiler macros, functions (including setf ones), generic functions and methods (including setf ones), method combinations, conditions, structures, classes and types.

The generated documentation includes every possible bit of information that introspecting can provide: documentation strings, lambda lists (including qualifiers and specializers where appropriate), slots (including type, allocation and initialization arguments), definition source file etc.

Every documented item provides a full set of cross-references to related items: ASDF component dependencies, parents and children, classes direct methods, super and subclasses, slot readers and writers, setf expanders access and update functions etc.

Finally, Declt produces exhaustive and multiple-entry indexes for every documented item.

Reference manuals are generated in Texinfo format (compatible, but not requiring Texinfo 5). From there it is possible to produce readable / printable output in info, HTML, PDF, DVI and PostScript with tools such as makeinfo, texi2dvi or texi2pdf.

The Declt reference manual is the primary example of documentation generated by Declt itself.

This morning, I came up with a nice little trick which made my day. Perhaps this is already well known or even idiomatic, but in case it is not, it goes like this.

Sometimes, I have to read a whole Lisp file containing more than just one toplevel form and get the contents as an unprocessed list of expressions. This happens for instance when loading a DSL program that needs post-treatment.

Usually, I end up doing something like this:

(with-open-file (stream filename)
  (loop :for expr = (read stream nil :eof)
	  :if (eq expr :eof)
	    :return exprs
	  :else
	    :collect expr :into exprs)))

But for some reason, this has always felt clunky to me. I mean, instead of ogling the family jewels of this poor shy file, I should be able to read it as a whole (hint: read-delimited-list) and preserve its intimacy.

And then I realized that the only thing that prevents me from using read-delimited-list is the lack of an ending parenthesis. But as always, Common Lisp immediately comes to the rescue, this time with its rich streams API. The idea is that you can create a string stream that just contains the closing parenthesis, and concatenate this stream at the end of the file one. I can now do something like this instead:

(with-open-file (stream filename)
  (read-delimited-list #\) (make-concatenated-stream stream (make-string-input-stream ")"))))

Not only it is shorter, it also looks much more elegant to me.

A new version of Clon, the Command-Line Options Nuker is out.

Amongst other things, the following improvements have been made:

• Support for ABCL has been updated, now that it provides a full MOP.
• A workaround for SBCL's CC environment variable problem has been implemented. If the variable is not set (required for sb-grovel), Clon now switches to restricted mode instead of aborting.
• The DUMP macro has been extend to accept a &rest argument that will be passed on to the underlying, implementation-specific, dumping facility.
• A contrib directory has been added, for storing unapplied patches, suggestions etc.

Grab it at the usual place.