I am making my existing .Net Application Scriptable for non programming users. I added lua, it works like a charm. Then I added debug functionality(pause/continue/step) via debug.sethook. It works also like a charm.
Now I realize that my Application needs edit and continue feature like Visual Studio has it. You pause the execution can edit the code and then continue from your current state with changes applied. This feature is very important to me. I thought this would be easy to do for scripting languages.
Everywhere I read that scripting languages can do this. But even after spending hours of searching I haven't found an Lua implementation yet. It hasn't to be Lua but hot swapping code in Lua would be my first choice.
How can the ability for the user be offered to pause and edit the script and than continue the execution with changes applied?
NOTE: It doesn't have to be Lua every scripting language would be okay
Update
#Schollii
Here is an example:
function doOnX()
if getValue() == "200" then
value = getCalculation()
doSomething() -- many function calls, each can take about 2s
doSomething()
doSomething()
print(value)
doX(value)
end
end
doOnX()
Thank you for your suggestions. This is how it might work:
I will use https://github.com/frabert/NetLua Its a very cool, well written 100% C# Lua Interpreter. It is generating an AST tree first and then directly executing it.
The parser needs to be modified. In Parser.cs public Ast.Block ParseString(string Chunk) there is a parseTree generated first. parseTree.tokens[i].locations are containing the exact position of each token. The Irony.Parsing.ParseTree is then parsed again and is converted to a NetLua.Ast.Block but the location information is missed. I will need to change that so later I will know which Statement is in which line.
Now each Statement from the AST tree is directly executed via EvalBlock. Debug functionality (like I have in my C Binding lua Interpreter DynamicLua via debug.setHook) needs to be added. This can be done in LuaInterpreter.cs internal static LuaArguments EvalBlock(`. Pause/continue/step functions should be no problem. I also can now add current line Highlighting because each statement contains position line information.
When the execution is paused and the code was edited the current LuaContxct is saved. It contains all variables. Also the last Statement with the last execution line is saved.
Now the code String is parsed again to a new AST tree. It gets executed. But all statements are skipped until the saved statement with the line statement is reached. The saved LuaContext is restored and execution can continue with all changes applied.
New variables could be also added after the last executed line, because a new NetLua.Ast.Assignment Statement could just add a new variable to the current LuaContext and everything should just work fine.
Will this work?
I think this is quite challenging and triicky to do right.
Probably the only way you could do that is if you recompile the chunk of code completely. In a function this would mean the whole function regardless of where edit is in function. Then call the function again. Clearly the function must be re-entrant else its side effects (like having incremented a global or upvalue) would have to be undone which isn't possible. If it is not reentrant it will still work just not give expected results (for example if the function increments a global variable by 1 calling it again will result in the global variable having been increased by 2 once the function finally returns).
But finding the lines in the script where the chunknstarts and ends would be tricky if truly generic solution. For specific solution you would have to post specific examples of scripts you want to run and examples of lines you would want to edit. If the whole user script gets recompiled and rerun then this is not a problem, but the side effects is still an issue, examples could help there too.
Related
I was wondering if there were a way to compute the size of a reg in Verilog. I researched it quite a bit, and found $size(a), but it's only in SystemVerilog, and it won't work in my verilog program.
Does anyone know an alternative for this??
I also wanted to ask as a side note; I'm having some trouble with my test bench in the sense that when I update a value in the file, that change is not taken in consideration when I simulate. I've been told I might have been using an old test bench but the one I am continuously simulating is the only one available in this project.
EDIT:
To give you an idea of what's the problem: in my code there is a "start" signal and when it is set to 1, the operation starts. Otherwise, it stays idle. I began writing the test bench with start=0, tested it and simulated it, then edited the test bench by setting start to 1. But when I simulate it, the start signal remains 0 in the waveform. I tried to check whether I was using another test bench, but it is the only test bench I am using in this project.
Given that I was on a deadline, I worked on the code so that it would adapt to the "frozen" test bench. I am getting now all the results I want, but I wanted to test some other features of my code, so I created a new project and copy pasted the code in new files (including the same test bench). But when I ran a simulation, the waveform displayed wrong results (even though I was using the exact same code in all modules and test bench). Any idea why?
Any help would be appreciated :)
There is a standardised way to do this, but it requires you to use the VPI, which I don't think you get on Modelsim's student edition. In short, you have to write C code, and dynamically link it to the simulator. In the C code, you can get object properties using routines such as vpi_get. Useful properites might be vpiSize, which is what you want, vpiLeftRange, vpiRightRange, and so on.
Having said all that, Verilog is essentially a static language, and objects have to be declared with a static width using constant expressions. Having a run-time method to determine an object's size is therefore of pretty limited value (since you should already know it), and may not solve whatever problem you actually have. Your question would make more sense for VHDL (and SystemVerilog?), which are much more dynamic.
Note on Icarus: the developers have pushed lots of SystemVerilog stuff back into the main language. If you take advantge of this you may find that your code is not portable.
Second part of your question: you need to be specific on what your problem actually is.
I'm trying to pass data which is continuously changed from the inside of one While loop to the inside of another While loop of a sub-vi. The main program on the left is constantly reading new data and the program on the right is adding 1 to the new value. My issue is that I cannot input new values to a While loop which is already running and thus my sub-vi is never updated. I've tried a global variable ("write" from the main program control and then "read" into the sub-vi) but that doesn't work either (same result as if the main were just passing data into the sub).
I apparently don't have enough reputation to post a picture of my program but I'm basically trying to run parallel loops (almost inside each other). Can anyone lend me an experienced hand?
The most common problem with while loops are based on lack of knowledge how exactly does the while loop work in LabVIEW.
First of all the information will be given outside the loop only if the condition terminal (right down corner of the loop) will be flagged as true.
If you want to pass the data earlier (while the loop is running) you have to choose easiest option:
Use queue (is the most common and well working). I can elaborate how this one work in practise if you want, or just try to run an example from LabVIEW help.
local/shared variables - you can define in your own library variables and pass the data by READ/WRITE option.
Please try to upload some documentation to an external server (as you are blocked here), and post a link, and then I could help you with a specific example.
Help»Find Examples. Search for "queue". Pick out an example with parallel loops.
You might want to look into Queues or Notifiers as means of passing data between running loops.
When writing my VBA macros I often used "F8" so as to debug the macro line by line. Is there a similar feature in Google Apps Script?
Similar, but not the same.
Google Apps Script is developed in a dedicated IDE1 called the Script Editor, which provides support for single-step execution and breakpoints, among other things.
For a quick introduction to debugging using the IDE, see this video. The Troubleshooting section of the online documentation includes a quick overview of the basics.
Debugging Functions with parameters
In the IDE you can select any function in your script for execution, and then select the "run" or "Debug" icons to start. Unfortunately, there is no way to pass parameters to a function this way, so here are a few ways you can deal with that.
Set defaults. There are numerous ways to define defaults in javascript, here is a picture of the debugger operating on a function using the simplest of them. The function toText() from this answer accepts a number as a parameter, so for this example we are forcing the default value to 21. The picture shows the debugger paused at line 40; if we continue stepping through the function we expect to end up with a result s == 'Twenty-one'.
Write a test function. This is a better approach than setting defaults, because it allows you to write multiple test cases, and it avoids polluting your target function with debug code. As an example, the target function flipFlopAndFly() and its test function test_flipFlopAndFly() were provided in this answer. The test function accesses the spreadsheet to provide appropriate data for testing the target, so we can easily modify the data for different tests. Note also, this function includes error checking, so it would not be appropriate to test by forcing default values.
There are many variations on these basic patterns, so feel free to adapt them to your own situation. It will help your debugging capability to think while you are writing about how you would step through your code:
Is each important object and value stored in a var, so you can see it?
Is your function result (return value) in a var?
Custom Functions
When developing or debugging custom functions that will be called from a spreadsheet, remember that you cannot "jump" into the IDE. If you need to step through the script, you will need to work entirely within the IDE to observe execution of your code. You can use the techniques described above to debug custom functions.
1 Integrated Development Environment
When using the magic function %edit from QtConsole with IPython, the call does not block, and does not execute the saved code. It does however save a temporary file...
I think this is intended behavior due to GUI editors and uncertainty, and whatever that reason is for not being able to communicate with subprocess (pyZMQ?).
What do you suggest as the best way to mix %edit/%run magics?
I would not mind calling two different commands (one to edit, and one after I have saved and execution is safe). But those commands need a way to synchronize this target file location, or someone to persist storage, and probably need some crude form of predicatably generating filenames such that you can edit more than one file at a time, and execute in arbitrarily. Session persistence is not a must.
Would writing my own magic do any good? Hope we can %edit macros soon, that would do well enough to make it work.
you shoudl be able to do %edit filename.py and %run filename.py. The non blocking behavior is expected, and IIRC due to technical reason. Not unsurmountable but difficult.
You could define your own magic if you wish, improvement are welcomed.
Hope we can %edit macros soon, that would do well enough to make it work.
For that too, PR are welcomed. I guess as a workaround/option you can %load macro which would put macro on input n+1 , edit it and redefine it, that might be a good extension for a cell magic %%macro macroname
If you have some executable code on your input (from QtConsole), you can type
%edit 1-5
This fires the editor, creates a temporarily file (automatically managed), and loads your input lines. This is nearly enough, now how to retrieve the name of that temp file pragmatically?
I see the print statement on Stdout, but its not visible to QtConsole AFAIK. Could maybe redirect stdout to catch that line, but that may not be an option anyway if your doing something else with stdout.
If I could retrieve the full pathname that was just created, this would be cake. Store it where some magics will know how to find it. Then issue a followup command when ready,pops the name off the stack, loads it into a macro, and run. All this with 2 input commands and no names to remember (unless you want to find and use that macro again, but for 1 shot stuff...)
How do I catch or retrieve the path of that temporary file?
I have a big program to run. Using valgrind it takes hours and hours to run. I heard that there is something where we can call valgrind for a specific function in the program. And rest of program will be executed normally(without valgrind env).
Can anybody help me with this. I tried searching it over internet , May be I am missing the term to search.
It all depends on what tool you're wanting to use. For callgrind (the profiler in valgrind) there is an option --toggle-collect=function to allow you to collect information inside a particular function and all its children.
However if the tool you're interested in is memcheck (for capturing leaks / memory errors) then there is no available command line option.
Googling "valgrind profile specific function only" and go "I feel lucky"
In addition to enabling instrumentation, you must also enable event collection for the parts
of your program you are interested in. By default, event collection is enabled everywhere.
You can limit collection to a specific function by using --toggle-collect=function. This will
toggle the collection state on entering and leaving the specified functions. When this option
is in effect, the default collection state at program start is "off". Only events happening
while running inside of the given function will be collected. Recursive calls of the given
function do not trigger any action.
More here