[PATCH 0/2] Add more context to E_constraint msg

[Mohammad-Reza Nabipoor]

Hi Jose.

This series enrich the msg field of E_constraint to give the user
more information of the definition location and evaluation location.

Example:

```
(poke) type A =  struct { int i == 1; }
(poke) var a = A{}
(poke) a.i++
unhandled constraint violation exception
failed expression
  i == 1
in field A.i evaluated at <stdin>:1:1 (defined at <stdin>:1:24)
```

I think, it's much more readable than

```
unhandled constraint violation exception
failed expression
  i == 1
in field A.i
```

Imagine when you're loading a pickle that's loading another one,
and somewhere there, a constraint violation is happening.

One thing that is, IMHO, even better, is to add a `detailed_info` field
to the exception, and report the whole stack of locations from the
first expr/stmt to the core expr that is the main point of failure.

Currently, I've introduced a `locationstack' to keep track of the
location info, and only reporting the location from top of that stack.


Regards,
Mohammad-Reza


Mohammad-Reza Nabipoor (2):
  pkl: report location of constraint definition
  pkl: report evaluation location in E_constraint exception

 ChangeLog                           |  54 +++++++++++++
 libpoke/pkl-ast.c                   |   6 ++
 libpoke/pkl-ast.h                   |   7 ++
 libpoke/pkl-gen.c                   |  77 +++++++++++++++++++
 libpoke/pkl-gen.pks                 |   4 +
 libpoke/pkl-insn.def                |   5 ++
 libpoke/pkl-rt.pk                   |  16 ++--
 libpoke/pkl-tab.y                   |  22 +++++-
 libpoke/pvm.jitter                  | 113 ++++++++++++++++++++++++++++
 testsuite/poke.pickles/pcap-test.pk |   3 +-
 10 files changed, 299 insertions(+), 8 deletions(-)

-- 
2.42.1