Bug 129235 – Use variadic templates to reduce the line count of wtf/text/StringConcatenate.h

• Component: New Bugs
• Status: RESOLVED DUPLICATE

[Sam Weinig]

Use variadic templates to reduce the line count of wtf/text/StringConcatenate.h

[Sam Weinig]

Created attachment 225012 [details]
Patch

[WebKit Commit Bot]

Attachment 225012 [details] did not pass style-queue:


ERROR: Source/WTF/wtf/text/StringConcatenate.h:518:  Do not use 'using namespace TryMakeStringDetails;'.  [build/using_namespace] [4]
Total errors found: 1 in 5 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Sam Weinig]

Created attachment 225013 [details]
Just the new code

Adding a file with just new code, as the diff is a bit hard to read.

[Sam Weinig]

(In reply to comment #2)
> Attachment 225012 [details] did not pass style-queue:
> 
> 
> ERROR: Source/WTF/wtf/text/StringConcatenate.h:518:  Do not use 'using namespace TryMakeStringDetails;'.  [build/using_namespace] [4]

I don't think this should be an error. The using namespace declaration is used inside a function.

[Sam Weinig]

Created attachment 225523 [details]
Patch

[Brent Fulgham]

This doesn't seem to work on Windows. Sometimes we run into problems with char*/wchar_t* 

Example error:

     WebSocketFrame.cpp
     1>C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(521): error C2079: 'adaptedStrings' uses undefined class 'std::tuple<WTF::StringTypeAdapter<StringType1>,WTF::StringTypeAdapter<const char*>>'
                 with
                 [
                     StringType1=WTF::StringAppend<const char *,WTF::String>
                 ] (..\Modules\websockets\WebSocketFrame.cpp)
                 C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringOperators.h(38) : see reference to function template instantiation 'WTF::PassRefPtr<WTF::StringImpl> WTF::tryMakeString<StringType1,StringType2>(StringType1,StringType2)' being compiled
                 with
                 [
                     StringType1=WTF::StringAppend<const char *,WTF::String>
         ,            StringType2=const char *
                 ]
                 C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringOperators.h(37) : while compiling class template member function 'WTF::StringAppend<WTF::StringAppend<const char *,WTF::String>,const char *>::operator WTF::String(void) const'
                 ..\Modules\websockets\WebSocketFrame.cpp(99) : see reference to function template instantiation 'WTF::StringAppend<WTF::StringAppend<const char *,WTF::String>,const char *>::operator WTF::String(void) const' being compiled
                 ..\Modules\websockets\WebSocketFrame.cpp(99) : see reference to class template instantiation 'WTF::StringAppend<WTF::StringAppend<const char *,WTF::String>,const char *>' being compiled
     1>C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(521): error C2078: too many initializers (..\Modules\websockets\WebSocketFrame.cpp)
     1>C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(521): error C2440: 'initializing' : cannot convert from 'const char *' to 'int' (..\Modules\websockets\WebSocketFrame.cpp)
                 There is no context in which this conversion is possible
     1>C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(522): error C2783: 'WTF::PassRefPtr<WTF::StringImpl> WTF::TryMakeStringDetails::tryMakeStringTuple(Tuple)' : could not deduce template argument for 'Indicies' (..\Modules\websockets\WebSocketFrame.cpp)
                 C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(509) : see declaration of 'WTF::TryMakeStringDetails::tryMakeStringTuple'
     1>C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(522): error C2780: 'WTF::PassRefPtr<WTF::StringImpl> WTF::TryMakeStringDetails::tryMakeStringTuple(Tuple &&,std::index_sequence<Index...>)' : expects 2 arguments - 1 provided (..\Modules\websockets\WebSocketFrame.cpp)
                 C:\cygwin\home\buildbot\WebKit\WebKitBuild\Release\include\private\wtf/text/StringConcatenate.h(503) : see declaration of 'WTF::TryMakeStringDetails::tryMakeStringTuple'

[Mark Rowe (bdash)]

I wrote up a very similar patch this evening since I wasn't aware of this one. I don't think it's necessary to use std::tuple for this.

[Joseph Pecoraro]

Comment on attachment 225523 [details]
Patch

This patch doesn't apply anymore, but it looks like it would be useful. Put up a rebaselined patch!

[Brent Fulgham]

(In reply to comment #8)
> Comment on attachment 225523 [details]
> Patch
> 
> This patch doesn't apply anymore, but it looks like it would be useful. Put
> up a rebaselined patch!

+1!

And I think our Windows builds can handle this now...

[Sam Weinig]

*** This bug has been marked as a duplicate of bug 147142 ***