Since Cython mixes C and Python semantics, some things may be a bit surprising or unintuitive. Work always goes on to make Cython more natural for Python users, so this list may change in the future.
Given two typed
a % bhas the same sign as the second argument (following Python semantics) rather than having the same sign as the first (as in C). The C behavior can be obtained, at some speed gain, by enabling the cdivision directive (versions prior to Cython 0.12 always followed C semantics).
Care is needed with unsigned types.
cdef unsigned n = 10; print(range(-n, n))will print an empty list, since
-nwraps around to a large positive integer prior to being passed to the
floattype actually wraps C
doublevalues, and the
inttype in Python 2.x wraps C