This repository contains the Preprocess command, which does simple match and fixpoint to eliminator (induction principle) translation for certain terms, as described in the DEVOID paper. This command is a part of the PUMPKIN PATCH plugin suite. Here it exists as a standalone plugin so that others can build on it as desired.
This plugin depends on Coq 8.9.1 and our Coq plugin library. The library is included automatically. To build the standalone plugin, run:
cd plugin
./build.shFor examples of using this plugin within another plugin, see PUMPKIN PATCH and DEVOID. For examples of using this command directly, see the coq directory.
Error messaging for this plugin is really difficult. Here are some quick guidelines:
If you get an error message about not being able to find an induction principle Foo_ind, Foo_rec, or Foo_rect,
you need to tell Coq to define an induction principle for that type. First, run this command:
Check Foo.Determine if your type is in Prop or not. If it is in Prop, then run these commands:
Scheme Minimality for Foo Sort Prop.
Scheme Induction for Foo Sort Set.
Scheme Induction for Foo Sort Type.Otherwise, run these commands:
Scheme Induction for Foo Sort Prop.
Scheme Induction for Foo Sort Set.
Scheme Induction for Foo Sort Type.This will tell Coq to generate induction principles. See this command for more information.
If a module you are processing includes or depends on an unsupported term, like one that uses mutual recursion,
you can use the opaque option to tell Preprocess Module to ignore it. For example, if you want to ignore Bar.bar and
Baz.baz when preprocessing the module Baz, you can write this:
Preprocess Module Baz as Baz' { opaque Bar.bar Baz.baz }.You can also tell Preprocess Module to ignore entire module, for example all definitions from the module Bar and its dependencies:
Preprocess Module Baz as Baz' { opaque Bar }.Do note, however, that you may run into issues with later definitions that depend on the definitions you ignore. So you may have to list several definitions to treat as opaque. See PreprocessModule.v for an example of this.
If you'd rather have Preprocess Module treat all dependencies as opaque by default, you can set the option:
Set Preprocess default opaque.You can then whitelist using transparent instead of opaque, for example:
Preprocess Module List as List' { transparent
(* list append and induction *)
Coq.Init.Datatypes
}.See DefaultOpaque.v for an example of this.
If you encounter an issue you can't solve, or you don't know why something isn't working, then please look at the output up to that error. It will print all of the definitions up until the one that it failed to process. You can then try to set that as opaque and continue, if you do not need it to use eliminators later on.
If you can't set a term as opaque or don't know why it isn't working but would like for it to work, then
when you report a bug, please include enough information to reproduce the bug, as well as the name of the
last definition Preprocess Module tries before failing. If you see a type error, please also include the
type error.
The original plugin was written by Nate Yazdani. Talia Ringer mostly ported it to a plugin and wrote a lot of library functions, then fixed some bugs later and added better error messaging and so on. Github history is not accurate here.
We use the MIT license because we think Coq plugins have a right not to use GPL. If this is wrong, please let us know kindly so we can fix this.