update stdcomplex wrapping #5748
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Simplifies the code and prevents std::complex
for that are not supported by c++.
• cppreference std::complex (template parameter requirements):
Notes that behavior is unspecified (and may fail to compile) if T is not
a (cv-unqualified) floating-point type. 
• Apache STDCXX user guide <complex> (older but explicit):
States the template argument “must be” one of
- float,
- double, or
- long double
Non cv-qualified types may compile on some standard libraries, fail on
others, and semantics are not guaranteed by the standard. The only fully
supported specializations are the floating-point ones.
This code seems to no longer be needed with newer swig wrappings.
dzenanz
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dzenanz
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Looks good upon cursory review.
| else: | ||
| assert ( | ||
| False | ||
| ), f"Unknown stdcomplex type: {typedef.name}, only D and F are supported." |
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| ), f"Unknown stdcomplex type: {typedef.name}, only D and F are supported." | |
| ), f"Unknown stdcomplex type: {typedef.name}, only LD, D, and F are supported." |
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@dzenanz I did into want to change this. I am looking at removing all LD support.
Implications for an automated wrapping pipeline (e.g., ITK/CastXML/SWIG)
Conclusion from references:
• SWIG’s own documentation does not support long double out of the box and treats it as unsupported. 
• There is active ongoing concern in the SWIG community about long double handling. 
• Scripting languages (Python, etc.) map floating types to double, not long double, so the practical utility of exposing long double wrappers is low. 
Therefore, the conservative/widely practiced advice is:
• Do not generate SWIG bindings for long double automatically.
• Prefer double versions of functions if available.
• Only expose long double if you write explicit custom typemaps and verify target support.
This is effectively equivalent to a blacklist approach for automatically wrapping long double in a general automation pipeline.
|
\azp run ITK.macOS.Python |
STYLE: Simplify std::complex wrapping
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