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-rw-r--r--.gitignore8
-rw-r--r--AUTHORS17
-rw-r--r--COPYING674
-rw-r--r--ChangeLog8
-rw-r--r--INSTALL365
-rw-r--r--Makefile29
-rw-r--r--Makefile.in70
-rw-r--r--NEWS0
-rw-r--r--README.md9
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diff --git a/.gitignore b/.gitignore
index d49d37c..5e24295 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
*.aux
*.glob
+*.tar.gz
*.vo
*.vok
*.vos
@@ -7,4 +8,9 @@
.CoqMakefile.d
.lia.cache
CoqMakefile
-CoqMakefile.conf \ No newline at end of file
+CoqMakefile.conf
+Makefile
+autom4te.cache
+config.log
+config.status
+configure
diff --git a/AUTHORS b/AUTHORS
new file mode 100644
index 0000000..8247b96
--- /dev/null
+++ b/AUTHORS
@@ -0,0 +1,17 @@
+Lambda is a Rocq library used for writing proofs about the untyped
+lambda calculus. It grew from an exercise in working through Forster
+and Smolka's 2017 paper "Weak Call-by-Value Lambda Calculus as a Model
+of Computation in Coq."
+
+The proofs in the original paper can be found at
+
+https://www.ps.uni-saarland.de/extras/L-computability/
+
+whose authors were
+
+Yannick Forster <forster@ps.uni-saarland.de>
+Gert Smolka <smolka@ps.uni-saarland.de>
+
+The additional proofs or rewrites contained here were made by
+
+Daniel Rostovtsev <dan@rostovtsev.org>
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..d344541
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
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+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ A tool for writing proofs about the untyped lambda calculus.
+ Copyright (C) 2026 Daniel Rostovtsev
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ lambda Copyright (C) 2026 Daniel Rostovtsev
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
diff --git a/ChangeLog b/ChangeLog
new file mode 100644
index 0000000..0bbf539
--- /dev/null
+++ b/ChangeLog
@@ -0,0 +1,8 @@
+2026-04-02 Daniel Rostovtsev <dan@rostovtsev.org>
+
+ v0.0.0: Fundamental theorems and objects for writing proofs about
+ the untyped lambda calculus. Includes:
+
+ - A weak call-by-value lambda calculus and beta reduction
+ - Church-Rosser Properties
+ - Uniform Confluence
diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..d3b6e4e
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,365 @@
+Installation Instructions
+*************************
+
+Basic Installation
+==================
+
+ The following shell commands:
+
+ test -f configure || ./bootstrap
+ ./configure
+ make
+ make install
+
+should configure, build, and install this package. The first line,
+which bootstraps, is intended for developers; when building from
+distribution tarballs it does nothing and can be skipped.
+
+ The following more-detailed instructions are generic; see the
+‘README’ file for instructions specific to this package. Some packages
+provide this ‘INSTALL’ file but do not implement all of the features
+documented below. The lack of an optional feature in a given package is
+not necessarily a bug. More recommendations for GNU packages can be
+found in the GNU Coding Standards.
+
+ Many packages have scripts meant for developers instead of ordinary
+builders, as they may use developer tools that are less commonly
+installed, or they may access the network, which has privacy
+implications. If the ‘bootstrap’ shell script exists, it attempts to
+build the ‘configure’ shell script and related files, possibly using
+developer tools or the network. Because the output of ‘bootstrap’ is
+system-independent, it is normally run by a package developer so that
+its output can be put into the distribution tarball and ordinary
+builders and users need not run ‘bootstrap’. Some packages have
+commands like ‘./autopull.sh’ and ‘./autogen.sh’ that you can run
+instead of ‘./bootstrap’, for more fine-grained control over
+bootstrapping.
+
+ The ‘configure’ shell script attempts to guess correct values for
+various system-dependent variables used during compilation. It uses
+those values to create a ‘Makefile’ in each directory of the package.
+It may also create one or more ‘.h’ files containing system-dependent
+definitions. Finally, it creates a shell script ‘config.status’ that
+you can run in the future to recreate the current configuration, and a
+file ‘config.log’ containing output useful for debugging ‘configure’.
+
+ It can also use an optional file (typically called ‘config.cache’ and
+enabled with ‘--cache-file=config.cache’ or simply ‘-C’) that saves the
+results of its tests to speed up reconfiguring. Caching is disabled by
+default to prevent problems with accidental use of stale cache files.
+
+ If you need to do unusual things to compile the package, please try
+to figure out how ‘configure’ could check whether to do them, and mail
+diffs or instructions to the address given in the ‘README’ so they can
+be considered for the next release. If you are using the cache, and at
+some point ‘config.cache’ contains results you don’t want to keep, you
+may remove or edit it.
+
+ The ‘autoconf’ program generates ‘configure’ from the file
+‘configure.ac’. Normally you should edit ‘configure.ac’ instead of
+editing ‘configure’ directly.
+
+ The simplest way to compile this package is:
+
+ 1. ‘cd’ to the directory containing the package’s source code.
+
+ 2. If this is a developer checkout and file ‘configure’ does not yet
+ exist, type ‘./bootstrap’ to create it. You may need special
+ developer tools and network access to bootstrap, and the network
+ access may have privacy implications.
+
+ 3. Type ‘./configure’ to configure the package for your system. This
+ might take a while. While running, ‘configure’ prints messages
+ telling which features it is checking for.
+
+ 4. Type ‘make’ to compile the package.
+
+ 5. Optionally, type ‘make check’ to run any self-tests that come with
+ the package, generally using the just-built uninstalled binaries.
+
+ 6. Type ‘make install’ to install the programs and any data files and
+ documentation. When installing into a prefix owned by root, it is
+ recommended that the package be configured and built as a regular
+ user, and only the ‘make install’ phase executed with root
+ privileges.
+
+ 7. Optionally, type ‘make installcheck’ to repeat any self-tests, but
+ this time using the binaries in their final installed location.
+ This target does not install anything. Running this target as a
+ regular user, particularly if the prior ‘make install’ required
+ root privileges, verifies that the installation completed
+ correctly.
+
+ 8. You can remove the program binaries and object files from the
+ source code directory by typing ‘make clean’. To also remove the
+ files that ‘configure’ created (so you can compile the package for
+ a different kind of computer), type ‘make distclean’. There is
+ also a ‘make maintainer-clean’ target, but that is intended mainly
+ for the package’s developers. If you use it, you may have to
+ bootstrap again.
+
+ 9. If the package follows the GNU Coding Standards, you can type ‘make
+ uninstall’ to remove the installed files.
+
+Compilers and Options
+=====================
+
+ Some systems require unusual options for compilation or linking that
+the ‘configure’ script does not know about. Run ‘./configure --help’
+for details on some of the pertinent environment variables.
+
+ You can give ‘configure’ initial values for configuration parameters
+by setting variables in the command line or in the environment. Here is
+an example:
+
+ ./configure CC=gcc CFLAGS=-g LIBS=-lposix
+
+ See “Defining Variables” for more details.
+
+Compiling For Multiple Architectures
+====================================
+
+ You can compile the package for more than one kind of computer at the
+same time, by placing the object files for each system in their own
+directory. To do this, you can use GNU ‘make’. ‘cd’ to the directory
+where you want the object files and executables to go and run the
+‘configure’ script. ‘configure’ automatically checks for the source
+code in the directory that ‘configure’ is in and in ‘..’. This is known
+as a “VPATH” build.
+
+ With a non-GNU ‘make’, it is safer to compile the package for one
+system at a time in the source code directory. After you have installed
+the package for one system, use ‘make distclean’ before reconfiguring
+for another system.
+
+ Some platforms, notably macOS, support “fat” or “universal” binaries,
+where a single binary can execute on different architectures. On these
+platforms you can configure and compile just once, with options specific
+to that platform.
+
+Installation Names
+==================
+
+ By default, ‘make install’ installs the package’s commands under
+‘/usr/local/bin’, include files under ‘/usr/local/include’, etc. You
+can specify an installation prefix other than ‘/usr/local’ by giving
+‘configure’ the option ‘--prefix=PREFIX’, where PREFIX must be an
+absolute file name.
+
+ You can specify separate installation prefixes for
+architecture-specific files and architecture-independent files. If you
+pass the option ‘--exec-prefix=PREFIX’ to ‘configure’, the package uses
+PREFIX as the prefix for installing programs and libraries.
+Documentation and other data files still use the regular prefix.
+
+ In addition, if you use an unusual directory layout you can give
+options like ‘--bindir=DIR’ to specify different values for particular
+kinds of files. Run ‘configure --help’ for a list of the directories
+you can set and what kinds of files go in them. In general, the default
+for these options is expressed in terms of ‘${prefix}’, so that
+specifying just ‘--prefix’ will affect all of the other directory
+specifications that were not explicitly provided.
+
+ The most portable way to affect installation locations is to pass the
+correct locations to ‘configure’; however, many packages provide one or
+both of the following shortcuts of passing variable assignments to the
+‘make install’ command line to change installation locations without
+having to reconfigure or recompile.
+
+ The first method involves providing an override variable for each
+affected directory. For example, ‘make install
+prefix=/alternate/directory’ will choose an alternate location for all
+directory configuration variables that were expressed in terms of
+‘${prefix}’. Any directories that were specified during ‘configure’,
+but not in terms of ‘${prefix}’, must each be overridden at install time
+for the entire installation to be relocated. The approach of makefile
+variable overrides for each directory variable is required by the GNU
+Coding Standards, and ideally causes no recompilation. However, some
+platforms have known limitations with the semantics of shared libraries
+that end up requiring recompilation when using this method, particularly
+noticeable in packages that use GNU Libtool.
+
+ The second method involves providing the ‘DESTDIR’ variable. For
+example, ‘make install DESTDIR=/alternate/directory’ will prepend
+‘/alternate/directory’ before all installation names. The approach of
+‘DESTDIR’ overrides is not required by the GNU Coding Standards, and
+does not work on platforms that have drive letters. On the other hand,
+it does better at avoiding recompilation issues, and works well even
+when some directory options were not specified in terms of ‘${prefix}’
+at ‘configure’ time.
+
+Optional Features
+=================
+
+ If the package supports it, you can cause programs to be installed
+with an extra prefix or suffix on their names by giving ‘configure’ the
+option ‘--program-prefix=PREFIX’ or ‘--program-suffix=SUFFIX’.
+
+ Some packages pay attention to ‘--enable-FEATURE’ and
+‘--disable-FEATURE’ options to ‘configure’, where FEATURE indicates an
+optional part of the package. They may also pay attention to
+‘--with-PACKAGE’ and ‘--without-PACKAGE’ options, where PACKAGE is
+something like ‘gnu-ld’. ‘./configure --help’ should mention the
+‘--enable-...’ and ‘--with-...’ options that the package recognizes.
+
+ Some packages offer the ability to configure how verbose the
+execution of ‘make’ will be. For these packages, running ‘./configure
+--enable-silent-rules’ sets the default to minimal output, which can be
+overridden with ‘make V=1’; while running ‘./configure
+--disable-silent-rules’ sets the default to verbose, which can be
+overridden with ‘make V=0’.
+
+Specifying a System Type
+========================
+
+ By default ‘configure’ builds for the current system. To create
+binaries that can run on a different system type, specify a
+‘--host=TYPE’ option along with compiler variables that specify how to
+generate object code for TYPE. For example, to create binaries intended
+to run on a 64-bit ARM processor:
+
+ ./configure --host=aarch64-linux-gnu \
+ CC=aarch64-linux-gnu-gcc \
+ CXX=aarch64-linux-gnu-g++
+
+If done on a machine that can execute these binaries (e.g., via
+‘qemu-aarch64’, ‘$QEMU_LD_PREFIX’, and Linux’s ‘binfmt_misc’
+capability), the build behaves like a native build. Otherwise it is a
+cross-build: ‘configure’ will make cross-compilation guesses instead of
+running test programs, and ‘make check’ will not work.
+
+ A system type can either be a short name like ‘mingw64’, or a
+canonical name like ‘x86_64-pc-linux-gnu’. Canonical names have the
+form CPU-COMPANY-SYSTEM where SYSTEM is either OS or KERNEL-OS. To
+canonicalize and validate a system type, you can run the command
+‘config.sub’, which is often squirreled away in a subdirectory like
+‘build-aux’. For example:
+
+ $ build-aux/config.sub arm64-linux
+ aarch64-unknown-linux-gnu
+ $ build-aux/config.sub riscv-lnx
+ Invalid configuration 'riscv-lnx': OS 'lnx' not recognized
+
+You can look at the ‘config.sub’ file to see which types are recognized.
+If the file is absent, this package does not need the system type.
+
+ If ‘configure’ fails with the diagnostic “cannot guess build type”.
+‘config.sub’ did not recognize your system’s type. In this case, first
+fetch the newest versions of these files from the GNU config package
+(https://savannah.gnu.org/projects/config). If that fixes things,
+please report it to the maintainers of the package containing
+‘configure’. Otherwise, you can try the configure option ‘--build=TYPE’
+where TYPE comes close to your system type; also, please report the
+problem to <config-patches@gnu.org>.
+
+ For more details about configuring system types, see the Autoconf
+documentation.
+
+Sharing Defaults
+================
+
+ If you want to set default values for ‘configure’ scripts to share,
+you can create a site shell script called ‘config.site’ that gives
+default values for variables like ‘CC’, ‘cache_file’, and ‘prefix’.
+‘configure’ looks for ‘PREFIX/share/config.site’ if it exists, then
+‘PREFIX/etc/config.site’ if it exists. Or, you can set the
+‘CONFIG_SITE’ environment variable to the location of the site script.
+A warning: not all ‘configure’ scripts look for a site script.
+
+Defining Variables
+==================
+
+ Variables not defined in a site shell script can be set in the
+environment passed to ‘configure’. However, some packages may run
+configure again during the build, and the customized values of these
+variables may be lost. In order to avoid this problem, you should set
+them in the ‘configure’ command line, using ‘VAR=value’. For example:
+
+ ./configure CC=/usr/local2/bin/gcc
+
+causes the specified ‘gcc’ to be used as the C compiler (unless it is
+overridden in the site shell script).
+
+Unfortunately, this technique does not work for ‘CONFIG_SHELL’ due to an
+Autoconf limitation. Until the limitation is lifted, you can use this
+workaround:
+
+ CONFIG_SHELL=/bin/bash ./configure CONFIG_SHELL=/bin/bash
+
+‘configure’ Invocation
+======================
+
+ ‘configure’ recognizes the following options to control how it
+operates.
+
+‘--help’
+‘-h’
+ Print a summary of all of the options to ‘configure’, and exit.
+
+‘--help=short’
+‘--help=recursive’
+ Print a summary of the options unique to this package’s
+ ‘configure’, and exit. The ‘short’ variant lists options used only
+ in the top level, while the ‘recursive’ variant lists options also
+ present in any nested packages.
+
+‘--version’
+‘-V’
+ Print the version of Autoconf used to generate the ‘configure’
+ script, and exit.
+
+‘--cache-file=FILE’
+ Enable the cache: use and save the results of the tests in FILE,
+ traditionally ‘config.cache’. FILE defaults to ‘/dev/null’ to
+ disable caching.
+
+‘--config-cache’
+‘-C’
+ Alias for ‘--cache-file=config.cache’.
+
+‘--srcdir=DIR’
+ Look for the package’s source code in directory DIR. Usually
+ ‘configure’ can determine that directory automatically.
+
+‘--prefix=DIR’
+ Use DIR as the installation prefix. See “Installation Names” for
+ more details, including other options available for fine-tuning the
+ installation locations.
+
+‘--host=TYPE’
+ Build binaries for system TYPE. See “Specifying a System Type”.
+
+‘--enable-FEATURE’
+‘--disable-FEATURE’
+ Enable or disable the optional FEATURE. See “Optional Features”.
+
+‘--with-PACKAGE’
+‘--without-PACKAGE’
+ Use or omit PACKAGE when building. See “Optional Features”.
+
+‘--quiet’
+‘--silent’
+‘-q’
+ Do not print messages saying which checks are being made. To
+ suppress all normal output, redirect it to ‘/dev/null’ (any error
+ messages will still be shown).
+
+‘--no-create’
+‘-n’
+ Run the configure checks, but stop before creating any output
+ files.
+
+‘configure’ also recognizes several environment variables, and accepts
+some other, less widely useful, options. Run ‘configure --help’ for
+more details.
+
+Copyright notice
+================
+
+ Copyright © 1994–1996, 1999–2002, 2004–2017, 2020–2024 Free Software
+Foundation, Inc.
+
+ Copying and distribution of this file, with or without modification,
+are permitted in any medium without royalty provided the copyright
+notice and this notice are preserved. This file is offered as-is,
+without warranty of any kind.
diff --git a/Makefile b/Makefile
deleted file mode 100644
index 520ce64..0000000
--- a/Makefile
+++ /dev/null
@@ -1,29 +0,0 @@
-# Makefile taken from Rocq Reference Manual 9.0.0
-
-# KNOWNTARGETS will not be passed along to CoqMakefile
-
-KNOWNTARGETS := CoqMakefile extra-stuff extra-stuff2
-
-# KNOWNFILES will not get implicit targets from the final rule, and so
-# depending on them won't invoke the submake
-# Warning: These files get declared as PHONY, so any targets depending
-# on them always get rebuilt
-
-KNOWNFILES := Makefile _CoqProject
-.DEFAULT_GOAL := invoke-coqmakefile
-
-CoqMakefile: Makefile _CoqProject
- $(COQBIN)coq_makefile -f _CoqProject -o CoqMakefile
-
-invoke-coqmakefile: CoqMakefile
- $(MAKE) --no-print-directory -f CoqMakefile \
- $(filter-out $(KNOWNTARGETS), $(MAKECMDGOALS))
-.PHONY: invoke-coqmakefile $(KNOWNFILES)
-
-####################################################################
-## Your targets here ##
-####################################################################
-
-# This should be the last rule, to handle any targets not declared above
-%: invoke-coqmakefile
- @true
diff --git a/Makefile.in b/Makefile.in
new file mode 100644
index 0000000..d43e8f1
--- /dev/null
+++ b/Makefile.in
@@ -0,0 +1,70 @@
+CONTRIB=$(DESTDIR)/@prefix@/lib/coq/user-contrib
+COQC=@COQC@
+COQBIN=@COQBIN@
+
+srcs=theories \
+ ChangeLog \
+ Makefile.in \
+ configure.ac \
+ configure \
+ _CoqProject \
+ NEWS \
+ AUTHORS \
+ INSTALL \
+ README.md \
+ COPYING
+
+# PACKAGE_NAME / PACKAGE_VERSION from AC_INIT
+rel=@PACKAGE_NAME@-@PACKAGE_VERSION@
+
+KNOWNFILES := Makefile _CoqProject configure.ac configure
+.DEFAULT_GOAL := invoke-coqmakefile
+
+configure: configure.ac
+ autoconf
+
+CoqMakefile: Makefile _CoqProject
+ $(COQBIN)/coq_makefile -f _CoqProject -o CoqMakefile
+
+invoke-coqmakefile: CoqMakefile
+ make COQBIN=$(COQBIN) COQLIBINSTALL=$(CONTRIB) \
+ -f CoqMakefile \
+ $(filter-out $(KNOWNTARGETS), $(MAKECMDGOALS))
+
+check:
+ make -f COQBIN=$(COQBIN) CoqMakefile validate
+
+AUTOCONF_FILES=aclocal.m4 \
+ autom4te.cache \
+ config.log \
+ config.status \
+ configure \
+ install-sh \
+ missing
+AUTOMAKE_FILES=Makefile
+BUILD_FILES=$$(find . -name "*.tar.gz") $$(find . -name "*~")
+distclean:
+ rm -rf $(AUTOCONF_FILES) $(AUTOMAKE_FILES)
+clean:
+ rm -rf $(BUILD_FILES)
+ rm -rf theories/*.vo theories/*.vok theories/*.glob theories/*.vos theories/*.aux
+ rm -rf CoqMakefile CoqMakefile.conf
+ rm -rf $(rel)
+
+dist: configure
+ rm -rf $(rel)
+ mkdir -p $(rel)
+ rm -rf theories/*.vo theories/*.vok theories/*.glob theories/*.vos theories/.*.aux
+ cp -r $(srcs) $(rel)
+ tar -czf $(rel).tar.gz $(rel)
+ rm -rf $(rel)
+
+distcheck: dist
+ tar -xzf $(rel).tar.gz
+ cd $(rel); ./configure; make
+ rm -rf $(rel)
+
+.PHONY: invoke-coqmakefile $(KNOWNFILES)
+
+%: invoke-coqmakefile
+ @true
diff --git a/NEWS b/NEWS
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/NEWS
diff --git a/README.md b/README.md
index 60b3e9a..d36aef5 100644
--- a/README.md
+++ b/README.md
@@ -20,13 +20,18 @@ Requirements:
- [rocq](https://rocq-prover.org/)
-The project is built with the GNU build system, but skips the
-configure step. Building is a one-liner.
+The project is built with the GNU build system.
```
+$ autoconf
+$ ./configure
$ make
```
+## Installation
+
+See `INSTALL` for instructions.
+
## Citations
1. Forster, Smolka 2017,
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..f186a1d
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,28 @@
+AC_INIT([lambda], [0.0.0], [dan@rostovtsev.org])
+
+# COQC search borrowed from the gappa project
+# https://gitlab.inria.fr/gappa/coq.git
+
+AC_DEFUN([AX_VERSION_GE], [AS_VERSION_COMPARE([$1],[$2],[$4],[$3],[$3])])
+
+AC_SUBST(COQVERSION)
+AC_ARG_VAR(COQC, [Coq compiler command [coqc]])
+AC_MSG_CHECKING([for coqc >= 8.12.0])
+COQC=`which coqc`
+COQVERSION=[`$COQC -v | sed -n -e 's/^.*version \([0-9][0-9.]*\).*$/\1/p' | awk -F. '{ printf("%d%02d%02d\n", $1,$2,$3); }'`]
+AX_VERSION_GE([$COQVERSION], [81200],
+ [ AC_MSG_RESULT([$COQC]) ],
+ [ AC_MSG_RESULT([no])
+ AC_MSG_ERROR([ *** Unable to find Coq (https://gitlab.inria.fr/gappa/coq.git)]) ])
+
+AC_SUBST(COQBIN)
+COQBIN=$(dirname $COQC)/
+
+echo
+echo "=== Summary ==="
+echo "Coq Compiler: $COQC"
+echo "Coq Binary Dir: $COQBIN"
+echo
+
+AC_CONFIG_FILES([Makefile])
+AC_OUTPUT