diff options
Diffstat (limited to 'absl/strings/internal/str_split_internal.h')
-rw-r--r-- | absl/strings/internal/str_split_internal.h | 55 |
1 files changed, 15 insertions, 40 deletions
diff --git a/absl/strings/internal/str_split_internal.h b/absl/strings/internal/str_split_internal.h index 6f5bc095..a2f41c15 100644 --- a/absl/strings/internal/str_split_internal.h +++ b/absl/strings/internal/str_split_internal.h @@ -51,9 +51,9 @@ ABSL_NAMESPACE_BEGIN namespace strings_internal { // This class is implicitly constructible from everything that absl::string_view -// is implicitly constructible from. If it's constructed from a temporary -// string, the data is moved into a data member so its lifetime matches that of -// the ConvertibleToStringView instance. +// is implicitly constructible from, except for rvalue strings. This means it +// can be used as a function parameter in places where passing a temporary +// string might cause memory lifetime issues. class ConvertibleToStringView { public: ConvertibleToStringView(const char* s) // NOLINT(runtime/explicit) @@ -65,41 +65,12 @@ class ConvertibleToStringView { : value_(s) {} // Matches rvalue strings and moves their data to a member. - ConvertibleToStringView(std::string&& s) // NOLINT(runtime/explicit) - : copy_(std::move(s)), value_(copy_) {} - - ConvertibleToStringView(const ConvertibleToStringView& other) - : copy_(other.copy_), - value_(other.IsSelfReferential() ? copy_ : other.value_) {} - - ConvertibleToStringView(ConvertibleToStringView&& other) { - StealMembers(std::move(other)); - } - - ConvertibleToStringView& operator=(ConvertibleToStringView other) { - StealMembers(std::move(other)); - return *this; - } + ConvertibleToStringView(std::string&& s) = delete; + ConvertibleToStringView(const std::string&& s) = delete; absl::string_view value() const { return value_; } private: - // Returns true if ctsp's value refers to its internal copy_ member. - bool IsSelfReferential() const { return value_.data() == copy_.data(); } - - void StealMembers(ConvertibleToStringView&& other) { - if (other.IsSelfReferential()) { - copy_ = std::move(other.copy_); - value_ = copy_; - other.value_ = other.copy_; - } else { - value_ = other.value_; - } - } - - // Holds the data moved from temporary std::string arguments. Declared first - // so that 'value' can refer to 'copy_'. - std::string copy_; absl::string_view value_; }; @@ -273,7 +244,11 @@ struct SplitterIsConvertibleTo // the split strings: only strings for which the predicate returns true will be // kept. A Predicate object is any unary functor that takes an absl::string_view // and returns bool. -template <typename Delimiter, typename Predicate> +// +// The StringType parameter can be either string_view or string, depending on +// whether the Splitter refers to a string stored elsewhere, or if the string +// resides inside the Splitter itself. +template <typename Delimiter, typename Predicate, typename StringType> class Splitter { public: using DelimiterType = Delimiter; @@ -281,12 +256,12 @@ class Splitter { using const_iterator = strings_internal::SplitIterator<Splitter>; using value_type = typename std::iterator_traits<const_iterator>::value_type; - Splitter(ConvertibleToStringView input_text, Delimiter d, Predicate p) + Splitter(StringType input_text, Delimiter d, Predicate p) : text_(std::move(input_text)), delimiter_(std::move(d)), predicate_(std::move(p)) {} - absl::string_view text() const { return text_.value(); } + absl::string_view text() const { return text_; } const Delimiter& delimiter() const { return delimiter_; } const Predicate& predicate() const { return predicate_; } @@ -336,7 +311,7 @@ class Splitter { Container operator()(const Splitter& splitter) const { Container c; auto it = std::inserter(c, c.end()); - for (const auto sp : splitter) { + for (const auto& sp : splitter) { *it++ = ValueType(sp); } return c; @@ -401,7 +376,7 @@ class Splitter { Container m; typename Container::iterator it; bool insert = true; - for (const auto sp : splitter) { + for (const auto& sp : splitter) { if (insert) { it = Inserter<Container>::Insert(&m, First(sp), Second()); } else { @@ -443,7 +418,7 @@ class Splitter { }; }; - ConvertibleToStringView text_; + StringType text_; Delimiter delimiter_; Predicate predicate_; }; |