Add make_bstr*(std::wstring_view)#634
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| #if defined(__WIL_OLEAUTO_H_) | ||
| #if defined(_STRING_VIEW_) || defined(__cpp_lib_string_view) | ||
| // Create wil::unique_bstr from std::wstring_view (regardless if not null terminated, or if it contains embedded nulls) | ||
| inline wil::unique_bstr make_bstr_nothrow(std::wstring_view source) noexcept |
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For bonus points - there is also the wil::zwstring_view overloads that enforce null termination but are ortherwise just a string_view.
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Can basic_zstring_view decay to basic_string_view? Or is there something special preventing object slicing?
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It might. I didn't actually check and just assumed a specialization would be needed.
| } | ||
| inline wil::unique_bstr make_bstr_failfast(std::wstring_view source) noexcept | ||
| { | ||
| return wil::unique_bstr(FAIL_FAST_IF_NULL_ALLOC(::SysAllocStringLen(source.data(), static_cast<UINT>(source.size())))); |
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Consider implementing this in terms of the nothrow variant, rather than repeating it here.
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| #if defined(__WIL_OLEAUTO_H_) | ||
| #if defined(_STRING_VIEW_) || defined(__cpp_lib_string_view) |
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In the general case, this is a problematic check because <version> also defines __cpp_lib_string_view even though <string_view> may not have been included. That said, this is the stl.h header, so it already (1) assumes STL use and (2) already includes <string_view> with the correct guards, so this concern is moot, but it does make the _STRING_VIEW_ check unnecessary. Better yet if you compare to a specific release. E.g. this could ideally become:
| #if defined(_STRING_VIEW_) || defined(__cpp_lib_string_view) | |
| #if __cpp_lib_string_view >= 201606L |
... which means you can just move this definition a few lines lower since this check is already present.
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WIL only provides only PCWSTR overloads:
This PR adds
wstring_viewoverloads callingSysAllocStringLenwith the view's data and size directly, correctly handling non-null-terminated string viewsThis works for non-null-terminated views (substrings, slices), avoids unnecessary and dangerous wcslen walk (we know the wstring_view's length), and is a strict superset of the existing API.
NOTE: A
PCWSTRimplicitly converts towstring_view, so these new overloads could replace the existing ones once C++17 is the floor. WIL still supports older standards, so these additional overloads is safer.