F# type inference (compiler output) - ide

Is there a way to get a structured output of the result of type inference by the F# compiler?
(I am trying to build a small IDE).

Assuming you have a file test.fs, you can use the following command to generate F# Signature File test.fsi, which contains type information about all top-level definitions:
Fsc.exe --sig:test.fsi test.fs
To get information about local variables, you'll need to use the F# compiler as a service. There is a simple command-line example that demonstrates how to call the API and you can also explore the F# binding for MonoDevelop.

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Kotlin/Native How to use a header-only C/C++ library

So I'm trying to use stb_image in my Kotlin/Native project and I am having trouble trying to include it in my project. It's a header only library and konan seems to expect a compiled object file anyways so I was wondering if there is any way of just generating the cstubs and then using the header for linking unless I have to compile a basic translation file since stb_image only requires you to have a translation unit that defines STB_IMAGE_IMPLEMENTATION however I have that defined in my compilerOpts -GSTB_IMAGE_IMPLEMENTATION. Would it be easier to just compile a translation unit, create the static object, and then link against it or does K/N have some way of doing that for me?
I am using Gradle Multiplatform so if there is some gradle script I can run then please let me know.
My -GSTB_IMAGE_IMPLEMENTATION is supposed to be -DSTB_IMAGE_IMPLEMENTATION and I needed to put my -I switch in my compilerOpts not linkerOpts.
I recommend actually creating a translation file but it's not required.
You can just give the header file with the compileropts as you've done and that should work.
You can look at this as a reference. I'm working on a wrapper in my free time.

What is the need of JVM when you can pass the source code?

i am new to java.
i wanted to know this.
what is the need to create the .class file in java ?
can't we just pass the source code to every machine so that each machine can compile it according to the OS and the hardware ?
I believe it's mostly for efficiency reasons.
From wikipedia http://en.wikipedia.org/wiki/Bytecode:
Bytecode, also known as p-code (portable code), is a form of
instruction set designed for efficient execution by a software
interpreter. Unlike human-readable source code, bytecodes are compact
numeric codes, constants, and references (normally numeric addresses)
which encode the result of parsing and semantic analysis of things
like type, scope, and nesting depths of program objects. They
therefore allow much better performance than direct interpretation of
source code.
(my emphasis)
And as others have mentioned possible weak obfuscation of the source code.
The main reason for the compilation is that the Virtual Machines which are used to host java classes and run them only understands bytecode
And since compiling a class each time to the language the virtual machine understands is expensive. That's the only reason why the source code is compiled into bytecode.
But we can also use some compilers which compiles source code directly into machine code.But that's a different story which I don't know about much.

How can I create a single Clojure source file which can be safely used as a script and a library without AOT compilation?

I’ve spent some time researching this and though I’ve found some relevant info,
Here’s what I’ve found:
SO question: “What is the clojure equivalent of the Python idiom if __name__ == '__main__'?”
Some techniques at RosettaCode
A few discussions in the Cojure Google Group — most from 2009
but none of them have answered the question satisfactorily.
My Clojure source code file defines a namespace and a bunch of functions. There’s also a function which I want to be invoked when the source file is run as a script, but never when it’s imported as a library.
So: now that it’s 2012, is there a way to do this yet, without AOT compilation? If so, please enlighten me!
I'm assuming by run as a script you mean via clojure.main as follows:
java -cp clojure.jar clojure.main /path/to/myscript.clj
If so then there is a simple technique: put all the library functions in a separate namespace like mylibrary.clj. Then myscript.clj can use/require this library, as can your other code. But the specific functions in myscript.clj will only get called when it is run as a script.
As a bonus, this also gives you a good project structure, as you don't want script-specific code mixed in with your general library functions.
EDIT:
I don't think there is a robust within Clojure itself way to determine whether a single file was launched as a script or loaded as a library - from Clojure's perspective, there is no difference between the two (it all gets loaded in the same way via Compiler.load(...) in the Clojure source for anyone interested).
Options if you really want to detect the manner of the launch:
Write a main class in Java which sets a static flag then launched the Clojure script. You can easily test this flag from Clojure.
Use AOT compilation to implement a Clojure main class which sets a flag
Use *command-line-args* to indicate script usage. You'll need to pass an extra parameter like "script" on the command line.
Use a platform-specific method to determine the command line (e.g. from the environment variables in Windows)
Use the --eval option in the clojure.main command line to load your clj file and launch a specific function that represents your script. This function can then set a script-specific flag if needed
Use one of the methods for detecting the Java main class at runtime
I’ve come up with an approach which, while deeply flawed, seems to work.
I identify which namespaces are known when my program is running as a script. Then I can compare that number to the number of namespaces known at runtime. The idea is that if the file is being used as a lib, there should be at least one more namespace present than in the script case.
Of course, this is extremely hacky and brittle, but it does seem to work:
(defn running-as-script
"This is hacky and brittle but it seems to work. I’d love a better
way to do this; see http://stackoverflow.com/q/9027265"
[]
(let
[known-namespaces
#{"clojure.set"
"user"
"clojure.main"
"clj-time.format"
"clojure.core"
"rollup"
"clj-time.core"
"clojure.java.io"
"clojure.string"
"clojure.core.protocols"}]
(= (count (all-ns)) (count known-namespaces))))
This might be helpful: the github project lein-oneoff describes itself as "dependency management for one-off, single-file clojure programs."
This lets you define everything in one file, but you do need the oneoff plugin installed in order to run it from the command line.

CDash Custom Dynamic Analysis

I'm trying to integrate custom dynamic analysis tools to CDash. Such as KWStyle, CppCheck and Visual Leak Detector.
I'v figured out that I need to generate a DynamicAnalysis.xml file and submit it to CDash, from CTest scripts.
I think I know how to run the external tool as a part of the ctest script.
Either by using these variables to change how ctest_memcheck() works
CTEST_MEMORYCHECK_COMMAND
CTEST_MEMORYCHECK_SUPPRESSIONS_FILE
CTEST_MEMORYCHECK_COMMAND_OPTIONS
or by running the tool from the execute_process() command.
But I'm a bit uncertain which one to use.
The main problem I think I have is, how can I extract errors from the output of the custom tool and include that information into the DynamicAnalysis.xml to submit?
The extreme solution i see is that i'd need to make a program that generates a valid DynamicAnalysis.xml file.
But the problem is that I don't know the syntax of the DefectList element in the XML file. I have found no answer from google and even the XML Schema for that file is unhelpful.
EDIT:
Looking at this:
http://www.cdash.org/CDash/viewDynamicAnalysis.php?buildid=987149
What draws my attention are the labels, especially the empty ones. I don't see how these would come from the DynamicAnalysis.xml file. Maybe it tracks any labels that have ever appearred? Can i create my own custom labels somehow?
Does CDash create the labels automatically, depending on the tool type? Does this block custom defect types?
I'm just guessing here, so the question is; can i create custom labels for my custom tool, just by generating a DynamicAnalysis.xml - file.
It occurred to me that the amount of different errors from CppCheck (static code analysis) is huge, compared to valgrind for instance. I'm not that certain that I should use the dynamic analysis. Maybe a custom build type (Continuous / Experimental / Nightly) thing would work better. Like this:
http://www.cdash.org/CDash/buildSummary.php?buildid=930174
I have no idea how to do this, i guess it requires meddling around with CDash code?
Which one would work better?
If you are using valgrind, you can simply set CTEST_MEMORYCHECK_COMMAND to the full path to valgrind, and ctest will generate the DynamicAnalysis.xml file for you from the valgrind output when you call ctest_memcheck.
The best way to understand the possible values that can appear in the DynamicAnalysis.xml file is to analyze the source code of CTest.
The file CMake/Source/CTest/cmCTestMemCheckHandler.cxx has the list of defect types in a variable named "cmCTestMemCheckResultLongStrings". Search through that file for references to that variable to see what the possible values are and how they are used to generate "<Defect/>" xml elements.
EDIT (for additional information):
You can also easily see what XML elements CDash is expecting by inspecting its source code. Specifically, the file "CDash/xml_handlers/dynamic_analysis_handler.php".
From what I'v learned so far, is that for a tool that runs on the tests made in the cmake script, the Dynamic Analysis is the thing.
For tools that run on the entire program, a custom Build.xml is the thing you need.
I found out that i can commit those files from the ctest_submit command by using the FILES parameter.
I also found out that you can add custom "build names" to the side of Continuous, Nightly, and others.
And that you can set the builds from certain machines to be automatically transferred under these.
The custom labels under DynamicAnalysis did come from somewhere in CDash, i can't remember where anymore.

what language is dotnet executable written in?

I thought it would be Common Intermediate Language, but in notepad it does not look like that at all. Does it just look uglier in reality than in tutorials? Or is it some bytecode form that is further compiled from CIL?
It's CIL is the name of the binary format, not of the "assembler" you're thinking of.
Can you possibly imagine that .NET assemblies would be text files?
A .NET executable is a binary file that has a PE header (same as a native executable, but with slightly different values). The PE header tells the OS to load the CLR, which in turn loads the assembly.
The content beyond the header is a binary representation of the CIL code, plus some metadata and other stuff. The text you see in tutorials is the text representation of CIL, in much the same way that the assembly language code you see in a tutorial about assembly language programming is just the text representation of the binary machine code.
See http://www.yetanotherchris.me/home/2010/7/12/inside-net-assemblies-part-1.html (among many others) for more information.
A .Net executable is usually not written, it is compiled from another language such as C#, F# or VB.Net.
The contents of a .Net executable can be viewed with the ILDASM tool.
The contents are first a manifest which is used for reflection, signatures or other meta-code purposes.
Secondly there are the MSIL instructions themselves. These are in a kind of bytecode format, but ILDASM will show you what the instructions are.
And there are sometimes resources such as imagery, sounds or other content packed into the executable.
The executable is just-in-time compiled to native code either during installation (I think this is uncommon), or as a precursor to execution. The resulting native code can be stored for reuse. (This is what I was told during PDC 2001, might be "out of date".)