acc

Life is fun, ATS is fun so, ATS error reporting should be fun too.

Pretty-printer/wrapper for the ats compiler/typechecker

Motivation

"...one can drastically reduce the need for debugging by making extensive use of types in programming." (source)

Understanding the typechecking errors though, can be quite difficult. The goal is to provide human readable messages.

Primarily seeks to make error reporting easier to read/understand and increase programming productivity. Places an importance of being memory frugal and explicit memory management (no memory leaks).

The application wraps patsopt, patscc and myatscc into one executable. The overall goal is to create a unified tool surrounding the ats compiler and other utilities.

Automated installer script acc-install.sh

Build

make

Install

make install

NOTE:
by default installs to $PATSHOME/bin (which should already be on PATH)

Testing

make testrun

Also, see TEST directory.

• TEST/TESTS/*.dats files (each contains errors)

Example

The error messages returned by current ATS compiler format:

command: patscc -tcats ./TEST/cfail.dats results:

.../TEST/cfail.dats: 570(line=35, offs=5) -- 610(line=35, offs=45): error(3): unsolved constraint: C3NSTRprop(C3TKmain(); S2Eeqeq(S2Eapp(S2Ecst(sub_int_int); S2Evar(r$14475$14476(23038)), S2Evar(r$14479$14480(23042))); S2Eapp(S2Ecst(add_int_int); S2Evar(r$14475$14476(23038)), S2Evar(r$14479$14480(23042))))) typechecking has failed: there are some unsolved constraints: please inspect the above reported error message(s) for information. exit(ATS): uncaught exception: _2home_2hwxi_2Research_2ATS_2dPostiats_2src_2pats_error_2esats__FatalErrorExn(1025)

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And the same file with acc:

command: acc ./TEST/cfail.dats results:

../TEST/cfail.dats: 35:5-45

35|     (FIB2(res1.0, res2.0) | res1.1 - res2.1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 
   error: unsolved constraint
          actual:  sub_int_int(r 14258, r 14262)
          needed:  add_int_int(r 14258, r 14262)


exit(ATS): uncaught exception: (1025)

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Usage

acc [whichcc] <filename.[d|s]ats>

(Optional) whichcc:

my         =>    myatscc 
pc         =>    patscc 
pm         =>    PATS
po         =>    patsopt 
gc         =>    PATS_GC
tcats      =>    patscc -tcats 
tc         =>    patscc -tcats 
lm         =>    PATS_LM
potc       =>    patsopt --typecheck --dynamic 
fly        =>    patscc -tcats 
c          =>    myatscc 
tcatsc     =>    patscc -tcats 

myatscc    =>    myatscc 
patscc     =>    patscc 
patscc_gc  =>    PATS
tcats      =>    patscc -tcats 
patsopt    =>    patsopt 

where 
{
  PATS          patscc -D_GNU_SOURCE -DATS_MEMALLOC_LIBC 
  PATS_GC       patscc -D_GNU_SOURCE -DATS_MEMALLOC_GCBDW 
  PATS_LM       patscc -D_GNU_SOURCE -DATS_MEMALLOC_LIBC -lm
}

filename:

valid file extensions: .dats or .sats

example:

acc my foo.dats
or
acc gc foo.dats -o foo

note: 
  one can also construct existing options. 
  for example, to use patscc with familiar options
  acc -pc -DATS_GNU_SOURCE -DATS_MEMALLOC_LIBC -O2 foo.dats -o foo

  or for patsopt,
  acc -po --output foo.tags --taggen -d foo.dats

Tips

Currently handles only a subset of error expressions from "ATS2/src/pats_staexp2.sats"

• expect additions
• output format will improve
• need advice for general format

some notation ::

*         #  :  prefix for external value or external kind (S2Eextype | S2Eextkind) 
*       [n]  :  existentially qualified type n (S2Eexi)
*       inf  :  intinf (S2Eintinf)
*      uni.  :  universally quantified type (S2Euni)
*   "g0int"  :  "g0int_t0ype"
* "g0float"  :  "g0float_t0ype"
*  "g0uint"  :  "g0uint_t0ype"
*   "g1int"  :  "g1int_int_t0ype"
*    "char"  :  "char_t0ype"
*    "char"  :  "char_int_t0ype"
*  "string"  :  "string_type"
*  "string"  :  "string_int_type" 
* "strnptr"  :  "strnptr_addr_int_vtype"
*    "list"  :  "list_t0ype_int_type"
* "list_vt"  :  "list_vt0ype_int_vtype"
*    XXXXX   :  where X is an integer (I believe is a tag of some sort)

Future

• The ideal form of the executable is one executable including a suite of smaller utilities (similar to haskells 'cabal').

  Future Additions ::

  • Give 'hints' for how to resolve certain errors.
  • Have a scale for levels of verbosity

    • one could remove all of the precise information (i.e. tag numbers and such)

      • 'describe' : a utility to describe a particular error message

      • option to print only first error

      • REPL-like evaluator (currently developing and refining)

      • Code formatter

      • Infer file type instead of having to explicitly pass the file type flag ( -d (for .dats) | -s (for .sats) )

      • Built-in options that automagically jsonize, depgen, taggen as opposed to "patsopt --jsonize -d foo.dats" | "patsopt --jsonize -s foo.sats"

        acc --jsonize ( FILE.[d|s]ats ) 
        acc --depgen  ( FILE.[d|s]ats ) 
        acc --taggen  ( FILE.[d|s]ats )
        

      • Incorporate other compilation tools that target languages other than C. options for -js / --atscc2js (for javascript) ...

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NOTE: This is LARGELY an unfinished product and is still being actively developed.