Cython: Passing ctuples as arguments to a class function

[branko623]

When passing a ctuple as an argument, the compiler complains:

C:\Users\bronx\.ipython\cython\_cython_magic_c30ac3a38886cdf8a43eb529120ef870.c(1300): error C2440: 'type cast': cannot convert from '__pyx_ctuple_int__and_int__and_int' to '__pyx_ctuple_int__and_int__and_int'
C:\Users\bronx\.ipython\cython\_cython_magic_c30ac3a38886cdf8a43eb529120ef870.c(1300): error C2198: '__pyx_pf_46_cython_magic_c30ac3a38886cdf8a43eb529120ef870_9someClass___iadd__': too few arguments for call

Posting here because this feels like a bug. You can pass ctuples as arguments to a function but not when classes are involved.

```%%cython
cdef class someClass:
cdef:
int r
def __iadd__(self, (int,int,int)c):
self.r = self.r + c[0] +c[1] + c[2]
print(self.r)
return self
cdef (int,int,int) p = (1,2,3)
r = someClass()
r+= p

[da-woods]

It seems to work for me with current master branch and 0.29.20. Are you using an older version of Cython? Or might this be an IPython magic issue?

[scoder]

Or an MSVC issue. @harambe623, which version of Python, Cython and Visual Studio / Visual-C / C compiler are you using?

[branko623]

Hmm it compiled on my debian machine. Closing this because MSVC must be the issue, though it is the latest (v142)... I will seek out a different compiler.

[scoder]

Maybe you could also try to investigate this a little more. There might be
a way for us to generate code that also works in MSVC here. Wouldn't be the
first time…

[branko623]

Got it! I was skeptical at first but it turns out that adding _# distutils: language = c++_ at the beginning will compile it without error

```

distutils: language = c++

cdef class someClass:
cdef:
int r
def __iadd__(self, (int,int,int)c):
self.r = self.r + c[0] +c[1] + c[2]
print(self.r)
return self
cdef (int,int,int) p = (1,2,3)
r = someClass()
r+= p