Parsetools enhancement

[crownedgrouse]

Optimizations:

• yecc : merge two subsequents tests into one
• leex : compile regex once
  New feature:
• leex : allow external definition inclusion
  Fix :
• Silent a warning

[rickard-green]

@crownedgrouse How come so many PRs? You can modify a PR if needed.

[crownedgrouse]

last one, sorry.

[uabboli]

Hi,

Sorry for the very long delay. I couldn't make up my mind about this
feature when the PR arrived, and I'm still not convinced there is a
use case for it. I think it's best for someone else to decide.

A few remarks, though:

IMHO, the modification in yecc.erl is unnecessary.

I think you can remove the line starting with _Filename in leex_SUITE
completely.

leex.erl already has superfluous spaces, but I think you should try
not to introduce new ones. The ones I can see in a quick glance are
at the end of {ok,Incfile} in parse_defs().

You should have at least one test case where the name of the included
file has characters greater than 255. Things I haven't checked are:
Is "/" allowed in filenames?
Do Windows filenames work as they should ("C:", "\")?

There should be test cases where the .xrl files have Latin-1 encoding
and UTF-8 encoding respectively, and they include a file with the same
encoding.

It is possible to give an encoding at the beginning of .xrl files.
Maybe it should be possible to state the encoding at the beginning of
included files as well, to be consistent. Test cases are needed for
that, of course.

What happens if a file includes itself? There are no warnings, it
seems.

There are few minor things in the docs that need to be fixed. Here is
a suggestion:

<p>Definitions are sometimes depending on OS, architecture, locale or 
  something else. In order to avoid to have as many <c>.xrl</c> files as 
  different cases, definitions can be pre-processed and written in a
  file referenced in the <c>Definitions.</c> section.
</p>

I removed the next paragraph as I don't think it's needed (and I
didn't quite get it).

<code>
  Definitions.
  include "external.inc"
  Rules.
  [...]      
</code>
<note><p>Included files can contain definitions only, 
without the <c>Definitions.</c> section. Several included files can be used, 
optionally mixed with the usual definitions in the <c>.xrl</c> file.</p></note>

Best regards,
Hans Bolinder, Erlang/OTP team, Ericsson