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9ebd93a774
prior to C++17. `absl::string_view` is now an alias for `std::string_view`. It is recommended that clients simply use `std::string_view`. PiperOrigin-RevId: 845822478 Change-Id: I220530c84118e5b9ef110baa002c232ac8f2c5f2
61 lines
2.1 KiB
C++
61 lines
2.1 KiB
C++
// Copyright 2017 The Abseil Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// https://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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// -----------------------------------------------------------------------------
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// File: string_view.h
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// -----------------------------------------------------------------------------
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//
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// Historical note: Abseil once provided an implementation of
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// `absl::string_view` as a polyfill for `std::string_view` prior to C++17. Now
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// that C++17 is required, `absl::string_view` is an alias for
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// `std::string_view`
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#ifndef ABSL_STRINGS_STRING_VIEW_H_
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#define ABSL_STRINGS_STRING_VIEW_H_
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#include <string_view>
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#include "absl/base/attributes.h"
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#include "absl/base/config.h"
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#include "absl/base/nullability.h"
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namespace absl {
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ABSL_NAMESPACE_BEGIN
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using std::string_view;
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// ClippedSubstr()
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//
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// Like `s.substr(pos, n)`, but clips `pos` to an upper bound of `s.size()`.
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// Provided because std::string_view::substr throws if `pos > size()`
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inline string_view ClippedSubstr(string_view s ABSL_ATTRIBUTE_LIFETIME_BOUND,
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size_t pos, size_t n = string_view::npos) {
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pos = (std::min)(pos, static_cast<size_t>(s.size()));
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return s.substr(pos, n);
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}
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// NullSafeStringView()
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//
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// Creates an `absl::string_view` from a pointer `p` even if it's null-valued.
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// This function should be used where an `absl::string_view` can be created from
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// a possibly-null pointer.
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constexpr string_view NullSafeStringView(const char* absl_nullable p) {
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return p ? string_view(p) : string_view();
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}
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ABSL_NAMESPACE_END
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} // namespace absl
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#endif // ABSL_STRINGS_STRING_VIEW_H_
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