Read-eval-print-loop for ATS

Presentation

I’m currently working on a read-eval-print-loop (REPL) for ATS which would allow not only to define values and use them, but would also give informations about the type of (static or dynamic) functions and symbols. This REPL isn’t really usable for now but can though be useful. Here is a (non-exhaustive) list of (un)supported functionalities:

A few supported functionalities

Display of fixity, associativity, precedence of operators
Display of the sort of static constants, the type of dynamic constants
Display of the sort of static expressions
Evaluation of dynamic expressions and display of the type
staload … declarations
Declarations of values by pattern matching
Tuples and records
Colorful display
…

A few unsupported functionalities

Easy-to-use command line interface (with arrow keys and history)
Display of some static expressions
Macros and preprocessor instructions
Functions definitions
Propositions, proofs
Viewtypes, linear values
…

Installation

Given that I’m using the source code of ATS/Anairiats, you must have the SVN version of the source code of the compiler. Then download this file and apply the following instructions (the patches are against revision 2451):

Apply all patches. Here is the function of each one:
- The patch repl_syntax_error.patch adds a syntax error exception in order to keep the lexbuf in a consistent state
- The patch repl_main_prelude.patch isolates the function prelude_load of ats_main.dats in the file ats_main_prelude.dats
- The patch repl_makefile.patch modifies the Makefiles to still be able to compile atsopt
Add the directory utils/atsrepl in $ATSHOME/
Compile everything with the command make in $ATSHOME/ (if you have an weird error, try make -B)
The REPL is now at $ATSHOME/bin/atsrepl

In short:

$ cd $ATSHOME
$ wget http://www.eleves.ens.fr/home/brunerie/docs/ats_repl.tgz
$ tar xvzf ats_repl.tgz
$ cat ATS_Repl_patch/repl_*.patch | patch -p0
$ cp -r ATS_Repl_patch/utils/atsrepl utils
$ make
$ ./bin/atsrepl