AFP Dijkstra's Shortest Path Algorithm - isabelle

For the AFP entry Dijkstra's Shortest Path Algorithm, both the proof outline and proof document were nonexistent *. Unfortunately, I did not find an IsaMakefile either to build those documents locally. What is the best way to get those documents?
Another question, as the Dijkstra.thy depends on a lot of other theories, is there a way to load everything faster?
*) It is fixed now.

(There seems to be something broken at AFP right now, please tell the editors about it.)
In general, you can download the sources of AFP entries and produce the documents yourself like this:
Get and unpack all AFP sources -- downloading separate entries is offered as well, but then you have to disentangle dependencies manually.
Invoke isabelle build like this:
isabelle build -d afp-2013-03-02 -o document=pdf -v Dijkstra_Shortest_Path
Here afp-2013-03-02 is the directory that was obtained by unpacking the current AFP sources.
See also the Isabelle System manual about "Isabelle sessions and build management", which is all new in Isabelle2013.
See isabelle build -b there to make things load faster, by producing persistent heap images from sessions.

The links in the AFP entry were indeed broken and should now be fixed again, sorry about that.
As Makarius writes, the AFP new uses Isabelle's new build system, i.e. has a ROOT file for each entry that can be used to check the associated theories and build the document.
Makarius' answer is pretty much the official way to do it, although I would additionally recommend setting up the AFP as a component. This gives you the following steps:
Download the AFP to e.g. ~/afp
Set it up as component e.g. by adding ~/afp to ~/.isabelle/Isabelle2013/components (see also AFP as a component)
build the entry with
isabelle afp_build Dijkstra_Shortest_Path

You can also have jEdit build the heap image for you. If the AFP is setup as a component (see the other answers for that), just start jEdit with
isabelle jedit -d '$AFP' -l Dijkstra_Shortest_Path
and jEdit will select Dijkstra_Shortest_Path as base logic and (re)build it if necessary.
If you make regular use of the AFP, it might be useful to add the AFP path by default. For this, create a file ROOTS in $ISABELLE_HOME_USER with the line $AFP in it (or add this line, if the file already exists).

Related

How to build session in Isabelle. (An example for AFP)

I want to make a submission, so I downloaded this example:
https://www.isa-afp.org/entries/Example-Submission.html
How to compile it? This is my main aim. Maybe a description may contain such command?
I've tried to find the answer here:
http://isabelle.in.tum.de/doc/system.pdf
But it contains strange lines, rectangles and circle instead of examples. I don't understand them.
So how one can compile this particular session in Isabelle?
The boxes describe the syntax of the ROOT file.
You have to read Section 2.3 of the document to know how to compile the document, but in short:
isabelle build -o browser_info -o document=pdf -d /path/to/Example-Submission Example-Submission

(ASDF 3) Is it possible to recursively load systems in subdirectories?

I know about using :modules, but what about when systems get nested? Suppose I have the following structure, relative to some unknown user directory:
foo/
-foo.asd
-bar/
--bar.asd
This could arise, for example, when using Git submodules. How shall I configure the (defsystem) call in foo.asd to load bar as a dependency, without modifying a config file outside of foo/ or demanding particular placement for the foo/ tree itself? Feels like it should be simple.
3 Feb. 2020: From #Svante's answer, it sounds like my question is really 'How do I dynamically ensure that foo/ and bar/ both get into the *source-registry*?' The ASDF manual makes me think this should do the trick:
(asdf:initialize-source-registry
'(:source-registry
(:tree "«absolute-path-to-foo»/")
:inherit-configuration))
though I have not seen an example of that usage.
26 Mar. 2020: The technique above seems to work fine, so I'm closing this question. ASDF 3 is excellent.
ASDF doesn't care about relative locations of .asd files. ASDF systems and their dependencies are completely orthogonal to file/directory structure and oblivious to any source version control.
It just looks in several locations for .asd files. Each such file then may contain definitions for systems. It will generally recurse into the configured folders, so any .asd file in a git submodule would usually also be found.
The definitions, e. g. of components, inside of an .asd file then work relatively from the location of that file.
In your example, if you give a :depends-on ("bar") option to the "foo" system, it would just work, no matter where bar.asd resides (as long as it is somewhere where ASDF finds it).
A bit more awareness would be required if you have several versions of a library. This might happen if you work on "foo" and "bar" at the same time, while a stable version of "bar" is also available, e. g. in a quicklisp dist. Then the lookup order comes into play, but usually your “personal” directories have precedence over “system” directories, so again, it would just work. For more control, you might want to look into qlot.

Randomize Make goals for a target

I have a C++ library and it has a few of C++ static objects. The library could suffer from C++ static initialization fiasco. I'm trying to vet unforeseen translation unit dependencies by randomizing the order of the *.o files during a build.
I visited 2.3 How make Processes a Makefile in the GNU manual and it tells me:
Goals are the targets that make strives ultimately to update. You can override this behavior using the command line (see Arguments to Specify the Goals) ...
I also followed to 9.2 Arguments to Specify the Goals, but a treatment was not provided. It did not surprise me.
Is it possible to have Make randomize its goals? If so, then how do I do it?
If not, are there any alternatives? This is in a test environment, so I have more tools available to me than just GNUmake.
Thanks in advance.
This is really implementation-defined, but GNU Make will process targets from left to right.
Say you have an OBJS variable with the objects you want to randomize, you could write something like (using e.g. shuf):
RAND_OBJS := $(shell shuf -e -- $(OBJS))
random_build: $(RAND_OBJS)
This holds as long as you're not using parallel make (-j option). If you are the order will still be randomized, but it will also depend on number of jobs, system load, current phase of the moon, etc.
Next release of GNU make will have --shuffle mode. It will allow you to execute prerequisites in random order to shake out missing dependencies by running $ make --shuffle.
The feature was recently added in https://savannah.gnu.org/bugs/index.php?62100 and so far is available only in GNU make's git tree.

make does not realize that a relative path name dependency is the same as an absolute pathname target

The following is a simplified makefile for a problem I'm having:
all: /tmp/makey/../filey
#echo All done
/tmp/filey:
#echo Filey
When I run make it says:
make-3.79.1-p7: * No rule to make target /tmp/makey/../filey', needed byall'. Stop.
Clearly it does not realize that /tmp/makey/../filey is the same as /tmp/filey. Any ideas how I can make this work?
Thanks
Ciao
-- Murali
Newer versions of GNU make have $(abspath ...) and $(realpath ...) functions you can apply to your prerequisites and targets to resolve the paths to the same string. If you've constructed these names yourself (for example, $(PREFIX)/../filey) then you can use $(dir $(PREFIX))filey instead.
Other than that, there's no way to solve this problem. Make uses string matching on targets and if the strings are not identical, they don't match (there's a special case to ignore the simple prefix ./) Even if make understood this distinction (by applying abspath itself to each target name, maybe) it would still not help in the face of symbolic links for example.
The only "real" answer would be for make to understand something about the underlying file system (device IDs and inodes for example) that let you talk about files without referring to their pathname. However, in a portable program like make doing this is problematic.

GNAT Programming Suite - source file not found

Ada is still new to me, so I am trying to find my way around the GPS IDE. I asked another question earlier, but I think this problem has precedence over that one, and may be at the root of my trouble.
When I compile, I am getting a long list of *warning: source file ... not found"
In my .gpr file, I have listed all of the spec and body source files and use the following naming scheme:
package Naming is
for Casing use "mixedcase";
for Dot_Replacement use ".";
for Spec_Suffix ("ada") use "_s.ada";
for Body_Suffix ("ada") use "_b.ada";
end Naming;
What is odd it the error messages all look either like this:
warning: source file "xxx_b.adb" not found
or this
warning: source file "xxx.adb" not found
Note that neither of these (xxxb.adb or xxx.adb) conform to the file specs, which should end with .ada.
Can someone explain what is going on here?
I'm 99% sure that the problem is one of the ones I mentioned in answer to your other question: GNAT does not normally support more than one compilation unit in a file. I got exactly the behaviour you describe with GPS and these files:
james_s.ada:
with Jane;
package James is
end James;
jim_s.ada:
package Jim is
end Jim;
package Jane is
end Jane;
The error message on compiling james_s.ada says it can't find Jane_s.ada, but when I ask GPS to go to the declaration of Jane it takes me to the "correct" line in jim_s.ada.
You could use gnatchop to split jim_s.ada, but it doesn't understand project files or naming conventions; you probably want to keep the existing names for the code that works, so you'd rename gnatchop's output as required.
However! to my great surprise, it turns out that GNAT does support having more than one compilation unit in a file, provided package Naming in the project file tells it about each unit in the file:
package Naming is
for Casing use "mixedcase";
for Dot_Replacement use ".";
for Spec_Suffix ("ada") use "_s.ada";
for Body_Suffix ("ada") use "_b.ada";
for Spec ("Jim") use "jim_s.ada" at 1;
for Spec ("Jane") use "jim_s.ada" at 2;
end Naming;
It's up to you whether to do this or to bite the bullet and use gnatchop, either on the multi-unit files or on the whole source tree.
First off, this isn't an Ada problem, its a Gnat problem. Other Ada compilers have no problem with the file names you are using.
However, Gnat is rather unique in that it expects there to be only one program unit (package body, package spec, stand-alone routine, etc) per source file. This is because it is also rather unique in that it expects to be able to find the source code for any program unit just by knowing that unit's Ada intentifier. Most other Ada compilers maintain some kind of library file that maps file names to program units, and you have to register all your files into it. (Whereas your typcial C compiler just leaves the problem of finding files for all your code up to the user entirely).
Generally the easiest thing to do with Gnat, the way that will cause you the least trouble, is to just use its default file naming convention (and of course don't put multiple program units in a single file.
If you already have some existing Ada code (perhaps developed for another compiler), the easiest way to import it into Gnat is typically to run the gnatchop tool on it all. So that's what I'd suggest you try.
From GPRbuild User's Guide:
Strings are used for values of attributes or as indexes for these attributes. They are in general case sensitive, except when noted otherwise [...]
Based on this, I believe you have to use "Ada" instead of "ada" as index for Spec_Suffix and Body_Suffix. I currently do not have access to the tools for testing this, so I suggest to just try it out.

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