[gdal-dev] CPLJSONDocument

[Dmitry Baryshnikov]

Hi Kurt,

Can you explain what should be done in PR?

Do you mean to replace all const char* to?

1. const char* -> const CPLString &

    const char *GetString(const char *pszName, const char *pszDefault =
    "") const; ->

    CPLString GetString(const CPLString &soName, const CPLString
    &soDefault = "") const;

or

2. const char* -> const std::string &

    const char *GetString(const char *pszName, const char *pszDefault =
    "") const; ->

    std::string GetString(const std::string &soName, const std::string
    &soDefault = "") const;

or?

Best regards,
     Dmitry

05.01.2018 18:54, Kurt Schwehr пишет:
> +1 for wrapping the old C code in some cleaner abstractions!
>
> But +10 for switching to a from the ground up C++ JSON library unless there
> are clear reasons for a core C library (I don't think there are)
>
> If we are talking about this kind of code, there are several things that
> have bugged me in general about GDAL for a long time.
>
> * Passing char *psz yada all over the place in pure C++ code.  A const
> std::string is usually not a noticeable expense and is a lot safer
> * CPLString when std::string will do just fine.  And we can write free
> functions to operate on strings.  I'm generally bothered by subclassing of
> std::string as CPLString.  After reading large amounts of C++ code, I think
> it adds more confusion than it ever helps over having clean free
> functions.  Interop and analysis with CPLString's is no fun.
>
> https://stackoverflow.com/questions/6006860/why-should-one-not-derive-from-c-std-string-class
>
> -kurt
>
> On Fri, Jan 5, 2018 at 7:44 AM, Sean Gillies <sean at mapbox.com> wrote:
>
>> Hi Dmitry,
>>
>> I scanned the PR and it seems reasonable to me. I'm barely a C++
>> programmer at all and it's clear to me, more clear than before. That said,
>> I'm not a fan of wrapping things that could be replaced. Have you looked
>> into whether a more performant C++ JSON library could be used? I haven't
>> run the benchmarks, but json-c compares pretty poorly to others in
>> https://github.com/miloyip/nativejson-benchmark.
>>
>>
>> On Wed, Jan 3, 2018 at 12:04 PM, Dmitry Baryshnikov <bishop.dev at gmail.com>
>> wrote:
>>
>>> Hi everybody,
>>>
>>> Happy new year and lot of success in 2018!
>>>
>>> I would like to discuss my pull request https://github.com/OSGeo/gdal/
>>> pull/282
>>>
>>> I created a thin wrapper around the json-c library which wide using in
>>> GDAL.
>>>
>>> This is C++ interface which hides C memory management and provides nice
>>> API. The web or disk json documents reading chunk by chunk with progress
>>> indication also added.
>>>
>>> In future, the json-c can be easily switch to something other without
>>> breaking the existing code.
>>>
>>> The CPLJSONDocument/CPLJSONObject/CPLJSONArray usage examples can be
>>> found in frmts/pds driver and c++ unit test in autotest/cpp/test_cpl.cpp.
>>>
>>> Is this ready to merge into the trunk? Any objections?
>>>
>>> Best regards,
>>>      Dmitry
>>>
>>>
>>> _______________________________________________
>>> gdal-dev mailing list
>>> gdal-dev at lists.osgeo.org
>>> https://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>>
>>
>> --
>> Sean Gillies
>>
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>
>

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