From ec6a4a831e57834bf4d7abb91fc8b298c2fbfcc2 Mon Sep 17 00:00:00 2001 From: David Kalnischkies Date: Fri, 15 Jan 2016 17:11:19 +0100 Subject: provide a constexpr char[] overload for APT::StringView The commit also adds a few trivial tests Git-Dch: Ignore --- apt-pkg/contrib/string_view.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'apt-pkg/contrib/string_view.h') diff --git a/apt-pkg/contrib/string_view.h b/apt-pkg/contrib/string_view.h index d4ff80028..ea38224e8 100644 --- a/apt-pkg/contrib/string_view.h +++ b/apt-pkg/contrib/string_view.h @@ -27,6 +27,10 @@ class StringView { const char *data_; size_t size_; + // without this little stunt the "char const *" overload is always preferred + // over char[], but if we got a char[] we can deduct the length at compile time + #define APT_T_IS_CHARPOINTER template{} && !std::is_array{}>::type* = nullptr> + public: static constexpr size_t npos = static_cast(-1); static_assert(APT::StringView::npos == std::string::npos, "npos values are different"); @@ -35,9 +39,10 @@ public: constexpr StringView() : data_(""), size_(0) {} constexpr StringView(const char *data, size_t size) : data_(data), size_(size) {} - StringView(const char *data) : data_(data), size_(strlen(data)) {} - StringView(std::string const & str): data_(str.data()), size_(str.size()) {} + template constexpr StringView(char const (&data)[N]) : StringView(data, N-1) {} + APT_T_IS_CHARPOINTER StringView(T data) : data_(data), size_(strlen(data)) {} + StringView(std::string const & str): data_(str.data()), size_(str.size()) {} /* Viewers */ constexpr StringView substr(size_t pos, size_t n = npos) const { @@ -114,7 +119,8 @@ public: } -inline bool operator ==(const char *other, APT::StringView that); -inline bool operator ==(const char *other, APT::StringView that) { return that.operator==(other); } +template inline bool operator ==(char const (&other)[N], APT::StringView that) { return that.operator==(other); } +APT_T_IS_CHARPOINTER inline bool operator ==(T other, APT::StringView that) { return that.operator==(other); } +#undef APT_T_IS_CHARPOINTER #endif -- cgit v1.2.3