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TMessagesProj/jni/voip/webrtc/absl/strings/strip.h

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+//
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: strip.h
+// -----------------------------------------------------------------------------
+//
+// This file contains various functions for stripping substrings from a string.
+#ifndef ABSL_STRINGS_STRIP_H_
+#define ABSL_STRINGS_STRIP_H_
+
+#include <cstddef>
+#include <string>
+
+#include "absl/base/attributes.h"
+#include "absl/base/macros.h"
+#include "absl/base/nullability.h"
+#include "absl/strings/ascii.h"
+#include "absl/strings/match.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
+// ConsumePrefix()
+//
+// Strips the `expected` prefix, if found, from the start of `str`.
+// If the operation succeeded, `true` is returned.  If not, `false`
+// is returned and `str` is not modified.
+//
+// Example:
+//
+//   absl::string_view input("abc");
+//   EXPECT_TRUE(absl::ConsumePrefix(&input, "a"));
+//   EXPECT_EQ(input, "bc");
+inline constexpr bool ConsumePrefix(absl::Nonnull<absl::string_view*> str,
+                                    absl::string_view expected) {
+  if (!absl::StartsWith(*str, expected)) return false;
+  str->remove_prefix(expected.size());
+  return true;
+}
+// ConsumeSuffix()
+//
+// Strips the `expected` suffix, if found, from the end of `str`.
+// If the operation succeeded, `true` is returned.  If not, `false`
+// is returned and `str` is not modified.
+//
+// Example:
+//
+//   absl::string_view input("abcdef");
+//   EXPECT_TRUE(absl::ConsumeSuffix(&input, "def"));
+//   EXPECT_EQ(input, "abc");
+inline constexpr bool ConsumeSuffix(absl::Nonnull<absl::string_view*> str,
+                                    absl::string_view expected) {
+  if (!absl::EndsWith(*str, expected)) return false;
+  str->remove_suffix(expected.size());
+  return true;
+}
+
+// StripPrefix()
+//
+// Returns a view into the input string `str` with the given `prefix` removed,
+// but leaving the original string intact. If the prefix does not match at the
+// start of the string, returns the original string instead.
+ABSL_MUST_USE_RESULT inline constexpr absl::string_view StripPrefix(
+    absl::string_view str ABSL_ATTRIBUTE_LIFETIME_BOUND,
+    absl::string_view prefix) {
+  if (absl::StartsWith(str, prefix)) str.remove_prefix(prefix.size());
+  return str;
+}
+
+// StripSuffix()
+//
+// Returns a view into the input string `str` with the given `suffix` removed,
+// but leaving the original string intact. If the suffix does not match at the
+// end of the string, returns the original string instead.
+ABSL_MUST_USE_RESULT inline constexpr absl::string_view StripSuffix(
+    absl::string_view str ABSL_ATTRIBUTE_LIFETIME_BOUND,
+    absl::string_view suffix) {
+  if (absl::EndsWith(str, suffix)) str.remove_suffix(suffix.size());
+  return str;
+}
+
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_STRINGS_STRIP_H_