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author | David Shah <dave@ds0.me> | 2020-07-27 13:50:42 +0100 |
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committer | GitHub <noreply@github.com> | 2020-07-27 13:50:42 +0100 |
commit | b39a2a502065ec1407417ffacdac2154385bf80f (patch) | |
tree | 3349c93ac87f5758009c53b3e2eb5b9a130cd0d6 /3rdparty/pybind11/docs/advanced/cast/index.rst | |
parent | e6991ad5dc79f6118838f091cc05f10d3377eb4a (diff) | |
parent | fe398ab983aee9283f61c288dc98d94542c30332 (diff) | |
download | nextpnr-b39a2a502065ec1407417ffacdac2154385bf80f.tar.gz nextpnr-b39a2a502065ec1407417ffacdac2154385bf80f.tar.bz2 nextpnr-b39a2a502065ec1407417ffacdac2154385bf80f.zip |
Merge pull request #477 from YosysHQ/pybind11
Move to pybind11
Diffstat (limited to '3rdparty/pybind11/docs/advanced/cast/index.rst')
-rw-r--r-- | 3rdparty/pybind11/docs/advanced/cast/index.rst | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/3rdparty/pybind11/docs/advanced/cast/index.rst b/3rdparty/pybind11/docs/advanced/cast/index.rst new file mode 100644 index 00000000..54c10570 --- /dev/null +++ b/3rdparty/pybind11/docs/advanced/cast/index.rst @@ -0,0 +1,42 @@ +Type conversions +################ + +Apart from enabling cross-language function calls, a fundamental problem +that a binding tool like pybind11 must address is to provide access to +native Python types in C++ and vice versa. There are three fundamentally +different ways to do this—which approach is preferable for a particular type +depends on the situation at hand. + +1. Use a native C++ type everywhere. In this case, the type must be wrapped + using pybind11-generated bindings so that Python can interact with it. + +2. Use a native Python type everywhere. It will need to be wrapped so that + C++ functions can interact with it. + +3. Use a native C++ type on the C++ side and a native Python type on the + Python side. pybind11 refers to this as a *type conversion*. + + Type conversions are the most "natural" option in the sense that native + (non-wrapped) types are used everywhere. The main downside is that a copy + of the data must be made on every Python ↔ C++ transition: this is + needed since the C++ and Python versions of the same type generally won't + have the same memory layout. + + pybind11 can perform many kinds of conversions automatically. An overview + is provided in the table ":ref:`conversion_table`". + +The following subsections discuss the differences between these options in more +detail. The main focus in this section is on type conversions, which represent +the last case of the above list. + +.. toctree:: + :maxdepth: 1 + + overview + strings + stl + functional + chrono + eigen + custom + |