tvl-depot/absl/strings/strip.h
Abseil Team 12bc53e031 Export of internal Abseil changes
--
c99f979ad34f155fbeeea69b88bdc7458d89a21c by Derek Mauro <dmauro@google.com>:

Remove a floating point division by zero test.

This isn't testing behavior related to the library, and MSVC warns
about it in opt mode.

PiperOrigin-RevId: 285220804

--
68b015491f0dbf1ab547994673281abd1f34cd4b by Gennadiy Rozental <rogeeff@google.com>:

This CL introduces following changes to the class FlagImpl:
* We eliminate the CommandLineFlagLocks struct. Instead callback guard and callback function are combined into a single CallbackData struct, while primary data lock is stored separately.
* CallbackData member of class FlagImpl is initially set to be nullptr and is only allocated and initialized when a flag's callback is being set. For most flags we do not pay for the extra space and extra absl::Mutex now.
* Primary data guard is stored in data_guard_ data member. This is a properly aligned character buffer of necessary size. During initialization of the flag we construct absl::Mutex in this space using placement new call.
* We now avoid extra value copy after successful attempt to parse value out of string. Instead we swap flag's current value with tentative value we just produced.

PiperOrigin-RevId: 285132636

--
ed45d118fb818969eb13094cf7827c885dfc562c by Tom Manshreck <shreck@google.com>:

Change null-term* (and nul-term*) to NUL-term* in comments

PiperOrigin-RevId: 285036610

--
729619017944db895ce8d6d29c1995aa2e5628a5 by Derek Mauro <dmauro@google.com>:

Use the Posix implementation of thread identity on MinGW.
Some versions of MinGW suffer from thread_local bugs.

PiperOrigin-RevId: 285022920

--
39a25493503c76885bc3254c28f66a251c5b5bb0 by Greg Falcon <gfalcon@google.com>:

Implementation detail change.

Add further ABSL_NAMESPACE_BEGIN and _END annotation macros to files in Abseil.

PiperOrigin-RevId: 285012012
GitOrigin-RevId: c99f979ad34f155fbeeea69b88bdc7458d89a21c
Change-Id: I4c85d3704e45d11a9ac50d562f39640a6adbedc1
2019-12-12 15:37:13 -05:00

91 lines
3 KiB
C++

//
// 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/macros.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 from the start of the given string, returning
// `true` if the strip operation succeeded or false otherwise.
//
// Example:
//
// absl::string_view input("abc");
// EXPECT_TRUE(absl::ConsumePrefix(&input, "a"));
// EXPECT_EQ(input, "bc");
inline bool ConsumePrefix(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 from the end of the given string, returning
// `true` if the strip operation succeeded or false otherwise.
//
// Example:
//
// absl::string_view input("abcdef");
// EXPECT_TRUE(absl::ConsumeSuffix(&input, "def"));
// EXPECT_EQ(input, "abc");
inline bool ConsumeSuffix(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 absl::string_view StripPrefix(
absl::string_view str, 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 absl::string_view StripSuffix(
absl::string_view str, 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_