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Merged
Ghabry merged 4 commits into from
Aug 23, 2020
Merged

Add StringView and Span #384

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e447acb
Add StringView class
mateofio Aug 16, 2020
bf88d53
StringView: use string-view-lite implementation
mateofio Aug 18, 2020
aa3c313
Add lcf::Span
mateofio Aug 18, 2020
9354b62
Remove StringView free functions
mateofio Aug 20, 2020
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8 changes: 6 additions & 2 deletions CMakeLists.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -208,6 +208,8 @@ set(LCF_HEADERS
src/lcf/reader_xml.h
src/lcf/saveopt.h
src/lcf/scope_guard.h
src/lcf/span.h
src/lcf/string_view.h
src/lcf/writer_lcf.h
src/lcf/writer_xml.h
src/generated/lcf/ldb/chunks.h
Expand Down Expand Up @@ -281,6 +283,8 @@ set(LCF_HEADERS
src/generated/lcf/rpg/trooppage.h
src/generated/lcf/rpg/trooppagecondition.h
src/generated/lcf/rpg/variable.h
src/lcf/third_party/span.h
src/lcf/third_party/string_view.h
)

list(TRANSFORM LCF_SOURCES PREPEND ${CMAKE_CURRENT_SOURCE_DIR}/)
Expand All @@ -290,7 +294,7 @@ list(APPEND LCF_HEADERS ${CMAKE_CURRENT_BINARY_DIR}/src/lcf/config.h)
target_sources(lcf PRIVATE ${LCF_SOURCES} PUBLIC ${LCF_HEADERS})

# IDE source grouping
foreach(SG LDB LMT LMU LSD RPG)
foreach(SG LDB LMT LMU LSD RPG THIRD_PARTY)
string(TOLOWER ${SG} LSG)
source_group("Source Files\\generated\\${SG}" REGULAR_EXPRESSION "generated/${LSG}_.*\\.cpp")
source_group("Header Files\\generated\\${SG}" REGULAR_EXPRESSION "generated/lcf/${LSG}/.*\\.h")
Expand Down Expand Up @@ -387,7 +391,7 @@ install(
RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})

set(LCF_INSTALL_HEADERS ${LCF_HEADERS})
foreach(S ldb lmt lmu lsd rpg)
foreach(S ldb lmt lmu lsd rpg third_party)
set(SUBDIR_HEADERS ${LCF_INSTALL_HEADERS})
list(FILTER SUBDIR_HEADERS INCLUDE REGEX "/${S}/")
install(FILES ${SUBDIR_HEADERS} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/lcf/${S})
Expand Down
7 changes: 7 additions & 0 deletions Makefile.am
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Expand Up @@ -21,6 +21,7 @@ lcflmtincludedir = $(includedir)/lcf/lmt
lcflmuincludedir = $(includedir)/lcf/lmu
lcflsdincludedir = $(includedir)/lcf/lsd
lcfrpgincludedir = $(includedir)/lcf/rpg
lcfthirdpartyincludedir = $(includedir)/lcf/third_party

lib_LTLIBRARIES = liblcf.la
liblcf_la_CPPFLAGS = \
Expand Down Expand Up @@ -210,6 +211,8 @@ lcfinclude_HEADERS = \
src/lcf/reader_xml.h \
src/lcf/saveopt.h \
src/lcf/scope_guard.h \
src/lcf/span.h \
src/lcf/string_view.h \
src/lcf/writer_lcf.h \
src/lcf/writer_xml.h

Expand Down Expand Up @@ -298,6 +301,10 @@ lcfrpginclude_HEADERS = \
src/generated/lcf/rpg/trooppagecondition.h \
src/generated/lcf/rpg/variable.h

lcfthirdpartyinclude_HEADERS = \
src/lcf/third_party/span.h \
src/lcf/third_party/string_view.h

nodist_lcfinclude_HEADERS = autogen/lcf/config.h

check_PROGRAMS = test_runner
Expand Down
3 changes: 3 additions & 0 deletions README.md
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Expand Up @@ -110,6 +110,7 @@ See the file [COPYING] for copying conditions.
### 3rd party software

liblcf code includes a copy of [inih] under New BSD license.
liblcf code includes a copy of [string-view-lite] and [span-lite] under Boost Software License, Version 1.0.
See the source code comment headers for license details.


Expand All @@ -119,3 +120,5 @@ See the source code comment headers for license details.
[#easyrpg at irc.freenode.net]: https://kiwiirc.com/nextclient/#ircs://irc.freenode.net/#easyrpg?nick=rpgguest??
[COPYING]: COPYING
[inih]: https://github.com/benhoyt/inih
[string-view-lite]: https://github.com/martinmoene/string-view-lite
[span-lite]: https://github.com/martinmoene/span-lite
41 changes: 41 additions & 0 deletions src/lcf/span.h
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@@ -0,0 +1,41 @@
/*
* This file is part of liblcf. Copyright (c) 2020 liblcf authors.
* https://github.com/EasyRPG/liblcf - https://easyrpg.org
*
* liblcf is Free/Libre Open Source Software, released under the MIT License.
* For the full copyright and license information, please view the COPYING
* file that was distributed with this source code.
*/

#ifndef LCF_SPAN_H
#define LCF_SPAN_H
#include <cstring>
#include <string>
#include <cassert>
#include <iterator>
#include <ostream>
#include <algorithm>

#define span_CONFIG_NO_EXCEPTIONS 1
#define span_FEATURE_WITH_CONTAINER 1
#define span_FEATURE_CONSTRUCTION_FROM_STDARRAY_ELEMENT_TYPE 1
#define span_FEATURE_MAKE_SPAN 1
#include <lcf/third_party/span.h>

namespace lcf {

using ExtentT = nonstd::span_lite::extent_t;
using nonstd::dynamic_extent;

template <typename T, ExtentT Extent= dynamic_extent>
using Span = nonstd::span<T,Extent>;

template <typename... Args>
constexpr inline auto MakeSpan(Args&&... args) noexcept -> decltype(nonstd::make_span(std::forward<Args>(args)...)) {
return nonstd::make_span(std::forward<Args>(args)...);
}


} // namespace lcf

#endif
76 changes: 76 additions & 0 deletions src/lcf/string_view.h
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@@ -0,0 +1,76 @@
/*
* This file is part of liblcf. Copyright (c) 2020 liblcf authors.
* https://github.com/EasyRPG/liblcf - https://easyrpg.org
*
* liblcf is Free/Libre Open Source Software, released under the MIT License.
* For the full copyright and license information, please view the COPYING
* file that was distributed with this source code.
*/

#ifndef LCF_STRING_VIEW_H
#define LCF_STRING_VIEW_H
#include <cstring>
#include <string>
#include <cassert>
#include <iterator>
#include <ostream>
#include <algorithm>

#define nssv_CONFIG_NO_EXCEPTIONS 1
#define nssv_CONFIG_CONVERSION_STD_STRING 1
#include <lcf/third_party/string_view.h>

namespace lcf {

template <typename CharT, typename Traits = std::char_traits<CharT>>
using BasicStringView = nonstd::basic_string_view<CharT,Traits>;

using StringView = BasicStringView<char>;
using WStringView = BasicStringView<wchar_t>;
using U16StringView = BasicStringView<char16_t>;
using U32StringView = BasicStringView<char32_t>;

template< class CharT, class Traits, class Allocator = std::allocator<CharT> >
std::basic_string<CharT, Traits, Allocator>
ToString(BasicStringView<CharT,Traits> sv, const Allocator& a = Allocator()) {
return nonstd::to_string(sv, a);
}

template< class CharT, class Traits, class Allocator >
BasicStringView<CharT, Traits>
ToStringView(const std::basic_string<CharT, Traits, Allocator>& s )
{
return nonstd::to_string_view(s);
}

// Make sure converting string to string is an error. To catch bugs.
template <typename C, typename T, typename A>
void ToString(const std::basic_string<C,T,A>&) = delete;

// We use macros instead of template to enable implicit string -> string_view conversion here.
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@Ghabry Ghabry Aug 19, 2020

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Can you give an example what you get with these macros that looks much worse without?

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@mateofio mateofio Aug 19, 2020 •
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With the macro I can write this:

std::string x;
Substr(x, 2, 3);

Without it, I have to write this because C++ templates aren't smart enough to figure out that basic_string<C,T,A> should be implicitly convertable to BasicStringView<C,T>;

Maybe C++17 deduction guides can help with this?

std::string x;
Substr(ToStringView(x), 2, 3);

Converting string -> string_view is normal and doesn't cost in performance, so it should be allowed freely. Going the other way means making a copy and thus should be flagged.

std::string y;
StringView x;
x = y; // Ok
y = x; // Error
y = ToString(x); // Ok, you meant to make a copy here.

#define LCF_STRING_VIEW_FREE_FUNCTIONS(TYPE)\
inline TYPE Substr(TYPE s, size_t pos = 0, size_t count = TYPE::npos) { return s.substr(pos, count); }\
inline bool StartsWith(TYPE str, TYPE prefix) { return str.starts_with(prefix); }\
inline bool StartsWith(TYPE str, TYPE::value_type prefix) { return str.starts_with(prefix); }\
inline bool StartsWith(TYPE str, const TYPE::value_type* prefix) { return str.starts_with(prefix); }\
inline bool EndsWith(TYPE str, TYPE suffix) { return str.ends_with(suffix); }\
inline bool EndsWith(TYPE str, TYPE::value_type suffix) { return str.ends_with(suffix); }\
inline bool EndsWith(TYPE str, const TYPE::value_type* suffix) { return str.ends_with(suffix); }

LCF_STRING_VIEW_FREE_FUNCTIONS(StringView)
LCF_STRING_VIEW_FREE_FUNCTIONS(WStringView)
LCF_STRING_VIEW_FREE_FUNCTIONS(U16StringView)
LCF_STRING_VIEW_FREE_FUNCTIONS(U32StringView)

#undef LCF_STRING_VIEW_FREE_FUNCTIONS

inline int SvAtoi(StringView str) {
const char* b = str.data();
const char* e = str.data() + str.length();
auto value = std::strtol(b, const_cast<char**>(&e), 10);
return e > b ? value : 0;
}

} // namespace lcf

#endif
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