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<p class=MsoNormal>I’m trying to set up a simple scripting environment
for non-programmers that can call into our C# codebase.<o:p></o:p></p>
<p class=MsoNormal>Python is a non-typed language, whereas C# is strongly
typed. This is one of the reasons IronPython was written.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>It seems that the solution presented by IronPython is to
expose .NET types into Python. If I want to call a C# function that takes
an array of doubles as an argument, I have a problem.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I know you can do something like:<o:p></o:p></p>
<p class=MsoNormal>Import System<o:p></o:p></p>
<p class=MsoNormal>Array=System.Array[float](range(10)) <o:p></o:p></p>
<p class=MsoNormal>To create and initialize the array with a sequence of
numbers. But now you are working with a .NET variable, not a Python
variable.<o:p></o:p></p>
<p class=MsoNormal>I can also do something similar with lists.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I don’t want to bring variable typing into Python,
because then it’s not Python. I also don’t want my users to
have to worry about this extra typing and keeping straight which variables need
it and which don’t.<o:p></o:p></p>
<p class=MsoNormal>I think the IronPython.Runtime should take care of this, but
it doesn’t.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m willing to write wrappers, in C#, for all the
functions (if needed) that I want to expose to Python. I’ve been knocking
myself out trying to do this. <o:p></o:p></p>
<p class=MsoNormal>I’ve been trying to accept a non-typed list, and use
it to fill an array of doubles. In my trial and error attempts, I’ve
prototyped my argument as <o:p></o:p></p>
<p class=MsoNormal>Public static void TestIt(IList inList) and public static
void TestIt(IronPython.runtime.List inList). They both act pretty much
the same. I’ve also tried using tuples.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>If my python list is created with pyList=range(10),
then passed as an argument<o:p></o:p></p>
<p class=MsoNormal>No matter what I do, I’ve been unsuccessful filling my
array of doubles using<o:p></o:p></p>
<p class=MsoNormal> myDoubles[i] = (double)inList[i]; (complains
that it can’t cast a value of infinity)<o:p></o:p></p>
<p class=MsoNormal>or any other type of casting I can come up with.<o:p></o:p></p>
<p class=MsoNormal>The debugger shows a nice list, with values 0-9.<o:p></o:p></p>
<p class=MsoNormal>inList[i].GetType() shows System.Int32. So why can’t
it cast?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>As an aside, if I start with pyList=map(float,range(10)),
then GetType() returns System.double and the cast works without a problem(and
probably isn’t needed).<o:p></o:p></p>
<p class=MsoNormal>But this requires the user to once again worry about the
variable type.<o:p></o:p></p>
<p class=MsoNormal>Based on this, I’m pretty sure if I set up a switch
statement on type in my wrapper, and assign a temp variable with the same type,
then the cast of the temp variable it would work.<o:p></o:p></p>
<p class=MsoNormal>But this sure seems clumsy!<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Does anyone have an idea of how to do this? I’m
sure I just haven’t hit on the right combination.<o:p></o:p></p>
<p class=MsoNormal>Basically I want the user to be able to use pyList =
range(10) and let me worry about converting it to double in a C# wrapper if
that’s what is needed.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m already resigned to writing wrappers in Python to
hide clr.Reference[type]() from my users when calling a C# functions that
requires an “out” or “ref” parameters.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks in advance for reading a post that I *<b>know</b>* is
as much rant as question. It’s just been frustrating ….<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><b><span style='color:#1F497D'>Mark Senko<o:p></o:p></span></b></p>
<p class=MsoNormal><span style='color:#4F81BD'>Complete Genomics, Inc.<o:p></o:p></span></p>
<p class=MsoNormal>2071 Stierlin Court<o:p></o:p></p>
<p class=MsoNormal>Mountain View, CA 94043<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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