I'm new to waf build tool and I've googled for answers but very few unhelpful links.
Does anyone know?
As wscript is essentially a python script, I suppose I could use the os package?
Don't use the os module, instead use the DEST_* variables:
ctx.load('compiler_c')
print (ctx.env.DEST_OS, ctx.env.DEST_CPU, ctx.env.DEST_BINFMT)
On my machine this would print ('linux', 'x86_64', 'elf'). Then you can dispatch on that.
You can use import at every point where you could use it any other python script.
I prefer using platform for programming a function os-agnostic instead on evaluate some attributes of os.
Writing the Build-related commands example in the waf book os-agnostic, could look something like this:
import platform
top = '.'
out = 'build_directory'
def configure(ctx):
pass
def build(ctx):
if platform.system().lower().startswith('win'):
cp = 'copy'
else:
cp = 'cp'
ctx(rule=cp+' ${SRC} ${TGT}', source='foo.txt', target='bar.txt')
Related
I'm trying to write a simple machine learning application in Ada, and also trying to find a good framework to use. My knowledge of one thing is extremely minimal, and of the other is somewhat minimal.
There are several nifty machine learning frameworks out there, and I'd like to leverage one for use with an Ada program, but I guess I'm just...at a loss. Can I use an existing framework written in Python, for instance and wrap (or I guess, bind?) the API calls in Ada? Should I just pass off the scripting capabilities? I'm trying to figure it out.
Case in point: Scikit (sklearn)
https://scikit-learn.org/stable/tutorial/text_analytics/working_with_text_data.html#
This does some neat stuff, and I'd like to be able to leverage this, but with an Ada program. Does anyone have advice from a similar experience?
I am just researching, so I have tried finding information.
http://www.inspirel.com/articles/Ada_Python_Binding.html
https://scikit-learn.org/stable/tutorial/text_analytics/working_with_text_data.html#
The inspirel solution is based on python2.7. If you're using anything from python3.5 onwards a few mods need to be made. On Linux, changing to say python 3.7, you'd just change
--for Default_Switches ("Ada") use ("-lpython2.7");
for Default_Switches ("Ada") use ("-lpython3.7");
but on windows, the libraries aren't dumped in a community lib so gnat doesn't know where to find them. All the packages are kept separately. The -L has to be added to tell the linker where to find the library. Alternatively, you can use for lib_dir. In my case, I did a non-admin install of python, so it looks something like
for Default_Switches ("Ada") use ("-L\Users\StdUser\AppData\Local\Programs\Python\Python37-32\libs", "-lpython37");
Note that on windows, the library is called python37: not python3.7. Use gprbuild instead of gnatmake -p, which has been deprecated. If you do all your mods correctly
gprbuild ada_main.gpr
should give you an executable in obj\ada_main.exe if it builds. If a later version of python is used, some edits need to be made
python_module.py
#print 'Hello from Python module'
print('Hello from Python module')
#print 'Python adding:', a, '+', b
print('Python adding:', a, '+', b)
ada_main.adb
-- Python.Execute_String("print 'Hello from Python!'");
Python.Execute_String("print('Hello from Python!')");
Some routines have been deprecated so the linkage has to change
python.adb
--pragma Import(C, PyInt_AsLong, "PyInt_AsLong");
pragma Import(C, PyInt_AsLong, "PyLong_AsLong");
--pragma Import(C, PyString_FromString, PyString_FromString");
pragma Import(C, PyString_FromString, "PyUnicode_FromString");
Running the build and executable should give
C:\Users\StdUser\My Documents\ada-python>gprbuild ada_main.gpr
Compile
[Ada] ada_main.adb
Bind
[gprbind] ada_main.bexch
[Ada] ada_main.ali
Link
[link] ada_main.adb
C:\Users\StdUser\My Documents\ada-python>obj\ada_main.exe
executing Python directly from Ada:
Hello from Python!
loading external Python module and calling functions from that module:
Hello from Python module!
asking Python to add two integers:
Python adding: 10 + 2
Ada got result from Python: 12
we can try other operations, too:
subtract: 8
multiply: 20
divide : 5
Remember to put the pythonxx.dll somewhere on your path otherwise it won't be able to find the library when it starts executing.
I have something like this in a BUILD file. I am un/commenting lines based on the operating system. Is there a graceful way to do this?
# Ubuntu
#shared_libraries = [
# "libboost_atomic.so"
#],
# OSX
shared_libraries = [
"libboost_atomic.dylib"
],
I haven't tried this however the bazel-build/rules_nodejs uses this kind of approach by wrapping the native binary and querying its's Node JS OS API.
OS Name Function(uses context given from user running node.exe)
UPDATE
Check here
Setting up a C++ Toolchain
This seems to be what you need.
From the GraalVM examples, they have code like this to run a single line of Python code:
context.eval("python", "\nprint('Hello polyglot world Python!');");
Yes that works fine in a Java program.
I can also run a Python program from the command line using the "graalpython" program.
My question is how do I run a python program from the Java example I mentioned above?
context.eval("python", "\nprint('Hello polyglot world Python!');");
I tried using the "file:" argument, but that didn't work or I'm doing something wrong.
For example, this did not work:
context.eval("python", "file: /path_to_python/test.py");
This line of code gives me:
Original Internal Error:
java.lang.RuntimeException: not implemented
So, maybe that answers my question, but I have to believe you can run a python script from a GRAAL program like you can a single line of code. Hence, this posting.
--
Is running a python program from within a Java program using graal "eval" supported? If so, I would very much appreciate an example of usage.
Thanks very much.
You need to build a Source object in order to eval a file:
File file = new File("/path_to_python/test.py");
Source source = Source.newBuilder("python", file).build();
context.eval(source);
I'm working on implementing a feature like Strict Java Deps for rules_scala.
I'd really like to have the ability to configure in runtime if this uses warn or error.
I seem to recall skylark rules can't create and access command-line flags but I don't recall if they can access existing ones?
Main difference is that existing ones are already parsed so maybe they are also passed in some ctx.
The flag you want (strict_java_deps) isn't available through Skylark at the moment. There's no reason we can't add it, though, filed #3295 to track.
For other flags, the context can access the configuration fragments, which can access some of the parsed command line flags. I think what you'd want is ctx.fragments, then use the fragments to get the java fragments, and then get the default_javac_flags from that:
# rules.bzl
def _impl(ctx):
print("flags: %s" % ctx.fragments.java.default_javac_flags)
...
frag = rule(
implementation = _impl,
fragments = ["java"], # Declare that this rule uses java fragments
)
Then:
$ bazel build --javacopt="-g:source,lines" :x
WARNING: /home/kchodorow/test/a/tester.bzl:2:3: flags: ["-g:source,lines"].
I'm connected to an Erlang node with -remsh. How do I modify the code path, in order to load a library that wasn't packaged into my release?
All necessary functions to manipulate code loading, path... are in the code module (see doc at erlang otp code module).
You could add the system paths to the list by doing the following:
[code:add_pathz(P) || P <- filelib:wildcard("/usr/lib/erlang/lib/*/ebin")].
After compiling some test code and connecting to a running node I was able to make it work with this:
(app#127.0.0.1)1> code:add_pathz("/path/to/my/compiled/beam").
(app#127.0.0.1)2> tester:hi().
hi!
ok
(app#127.0.0.1)3>