virtual C

1.11: adda/dstr/safe pointers/virtual C:
. adda's pointers can feature arithmetic exactly like c;
yet it can still remain safe because
the addresses are not absolute;
the pointers are actually actually just offsets .

PLY(Python-based Lex-Yacc) and pyCparser

8.20: web.adda/dev.py/ply
11.2: PLY compared with ANTLR:

There are several reasons to use ANTLR
over one of the Python parsers
like PLY and PyParsing.
The GUI interface is very nice,
it has a sophisticated understanding of
how to define a grammar,
it's top-down approach means the
generated code is easier to understand,
tree-grammers simplify some otherwise
tedious parts of writing parsers,
and it supports multiple output languages:
its builds parsers best in C, C# and Java;
but also has some support for generating Python .

ANTLR is written in Java;

Unlike the standard yacc/lex combination,
it combines both lexing and parsing rules
into the same specification document,
and adds tree transformation rules
for manipulating the AST.

. so, if you prefer python tools over Java, PLY ahead!

programming in-the-large with c

8.5: news.adda/translate/info'hiding n type-safe linking:

2007 CMod Modular Information Hiding
and Type Safe Linking for C

CMod, provides a sound module system for C;
it works by enforcing a set of rules that are
based on principles of modular reasoning
and on current programming practice.

CMod's rules safely enforce the convention
that .h header files are module interfaces
and .c source files are module implementations.
Although this convention is well known,
developing CMod's rules revealed many subtleties
to applying the basic pattern correctly.
CMod's rules have been proven formally
to enforce both information hiding
and type-safe linking.

lang's for supercomputer concurrency

adda/concurrency/lang's for supercomputer concurrency
7.27:
. the DARPA`HPCS program
(High Productivity Computing Systems)
is meant to tame the costs of HPC
(High Performance Computing)
-- HPC is the use of supercomputers for
simulations to solve problems in
chemistry, physics, ecology, sociology,
and esp'ly warfare .
. programmer productivity
means making it easier to develope
code that can make full use of
a supercomputer's concurrency .
. the main source of the cost
is a lack of smart software tools
that can turn science experts
into computer coders .
. toward this end, they are funding
the design of new concurrency lang's .
7.28:
. the DoD and DARPA already made
quite an investment in the
Ada concurrency lang',
a language designed for expressing
the sort of concurrency needed by
embedded system engineers; 7.31:
but, the software developer community
spurned Ada as soon as there was
something better ...
. pascal was popular before '85,
and when Ada arrived '83,
it was popular too;
then came the Visual version
of Basic (familiar and slick).
. the top demanded langs by year were:
'85: C, lisp, Ada, basic;
'95: v.basic, c++, C, lisp, Ada;
'05: Java, C, c++, perl, php,

. the only currently popular lang's
meant for exploiting multi-core cpu's
if not other forms of concurrency, are:
(3.0% rating) obj'c 2.0 (with blocks)
(0.6% rating) Go
(0.4% rating) Ada
7.29:
. whether or not Ada's concurrency model
is well-suited for supercomputers
as well as embedded systems,
it is not increasing coder'productivity .
. while Ada boosted productivity beyond
that offered by C,
it was nevertheless proven to do
less for productivity than Haskell .

HPC Productivity 2004/Kepner{ 2003(pdf), 2004(pdf) }:
. lang's were compared for
expressiveness vs performance:
. the goal of a high-performance lang'
is to have the expressiveness
of Matlab and Python,
with the performance of VHDL
(VHDL is a version of Ada for ASICs ).
. UPC (Unified Parallel C) and Co-array Fortran
are half way to high-productivity
merely by using PGAS
(Partitioned global address space)
rather than MPI
(Message Passing Interface).
. the older tool set: C, MPI, and openMP
is both slow and difficult to use .

. the 2 lang's that DARPA is banking on now
are Cray`Chapel, and IBM`X10 Java .
. they were also funding Sun`Fortress
until 2006,
which features a syntax like advanced math
-- the sort of greek that physics experts
are expected to appreciate .