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f28d30df5769bb832dec3ff36d2fcd2bcdf494a3 by Shaindel Schwartz <shaindel@google.com>:

Internal change

PiperOrigin-RevId: 201046831

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711715a78b7e53dfaafd4d7f08a74e76db22af88 by Mark Barolak <mbar@google.com>:

Internal fix

PiperOrigin-RevId: 201043684

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64b53edd6bf1fa48f74e7f5d33f00f80d5089147 by Shaindel Schwartz <shaindel@google.com>:

Remove extra whitespace

PiperOrigin-RevId: 201041989

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0bdd2a0b33657b688e4a04aeba9ebba47e4dc6ca by Shaindel Schwartz <shaindel@google.com>:

Whitespace fix.

PiperOrigin-RevId: 201034413

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3deb0ac296ef1b74c4789e114a8a8bf53253f26b by Shaindel Schwartz <shaindel@google.com>:

Scrub build tags. No functional changes.

PiperOrigin-RevId: 201032927

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da75d0f8b73baa7e8f4e9a092bba546012ed3b71 by Alex Strelnikov <strel@google.com>:

Internal change.

PiperOrigin-RevId: 201026131

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6815d80caa19870d0c441b6b9816c68db41393a5 by Tom Manshreck <shreck@google.com>:

Add documentation for our LTS snapshot branches

PiperOrigin-RevId: 201025191

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64c3b02006f39e6a8127bbabf9ec947fb45b6504 by Greg Falcon <gfalcon@google.com>:

Provide absl::from_chars for double and float types.  This is a forward-compatible implementation of std::from_chars from C++17.

This provides exact "round_to_nearest" conversions, and has some nice properties:

* Works with string_view (it can convert numbers from non-NUL-terminated buffers)
* Never allocates memory
* Faster than the standard library strtod() in our toolchain
* Uses integer math in its calculations, so is unaffected by floating point environment
* Unaffected by C locale

Also change SimpleAtod/SimpleAtoi to use this new API under the hood.

PiperOrigin-RevId: 201003324

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542869258eb100779497c899103dc96aced52749 by Greg Falcon <gfalcon@google.com>:

Internal change

PiperOrigin-RevId: 200999200

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3aba192775c7f80e2cd7f221b0a73537823c54ea by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 200947470

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daf9b9feedd748d5364a4c06165b7cb7604d3e1e by Mark Barolak <mbar@google.com>:

Add an absl:: qualification to a usage of base_internal::SchedulingMode outside of an absl:: namespace.

PiperOrigin-RevId: 200748234

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a8d265290a22d629f3d9bf9f872c204200bfe8c8 by Mark Barolak <mbar@google.com>:

Add a missing namespace closing comment to optional.h.

PiperOrigin-RevId: 200739934

--
f05af8ee1c6b864dad2df7c907d424209a3e3202 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 200719115
GitOrigin-RevId: f28d30df5769bb832dec3ff36d2fcd2bcdf494a3
Change-Id: Ie4fa601078fd4aa57286372611f1d114fdec82c0

1 files changed, 115 insertions, 0 deletions

diff --git a/absl/strings/charconv.h b/absl/strings/charconv.h
new file mode 100644
index 000000000000..3e313679c961
--- /dev/null
+++ b/absl/strings/charconv.h
@@ -0,0 +1,115 @@
+// Copyright 2018 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
+//
+//      http://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.
+
+#ifndef ABSL_STRINGS_CHARCONV_H_
+#define ABSL_STRINGS_CHARCONV_H_
+
+#include <system_error>  // NOLINT(build/c++11)
+
+namespace absl {
+
+// Workalike compatibilty version of std::chars_format from C++17.
+//
+// This is an bitfield enumerator which can be passed to absl::from_chars to
+// configure the std::string-to-float conversion.
+enum class chars_format {
+  scientific = 1,
+  fixed = 2,
+  hex = 4,
+  general = fixed | scientific,
+};
+
+// The return result of a std::string-to-number conversion.
+//
+// `ec` will be set to `invalid_argument` if a well-formed number was not found
+// at the start of the input range, `result_out_of_range` if a well-formed
+// number was found, but it was out of the representable range of the requested
+// type, or to std::errc() otherwise.
+//
+// If a well-formed number was found, `ptr` is set to one past the sequence of
+// characters that were successfully parsed.  If none was found, `ptr` is set
+// to the `first` argument to from_chars.
+struct from_chars_result {
+  const char* ptr;
+  std::errc ec;
+};
+
+// Workalike compatibilty version of std::from_chars from C++17.  Currently
+// this only supports the `double` and `float` types.
+//
+// This interface incorporates the proposed resolutions for library issues
+// DR 3800 and DR 3801.  If these are adopted with different wording,
+// Abseil's behavior will change to match the standard.  (The behavior most
+// likely to change is for DR 3801, which says what `value` will be set to in
+// the case of overflow and underflow.  Code that wants to avoid possible
+// breaking changes in this area should not depend on `value` when the returned
+// from_chars_result indicates a range error.)
+//
+// Searches the range [first, last) for the longest matching pattern beginning
+// at `first` that represents a floating point number.  If one is found, store
+// the result in `value`.
+//
+// The matching pattern format is almost the same as that of strtod(), except
+// that C locale is not respected, and an initial '+' character in the input
+// range will never be matched.
+//
+// If `fmt` is set, it must be one of the enumerator values of the chars_format.
+// (This is despite the fact that chars_format is a bitmask type.)  If set to
+// `scientific`, a matching number must contain an exponent.  If set to `fixed`,
+// then an exponent will never match.  (For example, the std::string "1e5" will be
+// parsed as "1".)  If set to `hex`, then a hexadecimal float is parsed in the
+// format that strtod() accepts, except that a "0x" prefix is NOT matched.
+// (In particular, in `hex` mode, the input "0xff" results in the largest
+// matching pattern "0".)
+absl::from_chars_result from_chars(const char* first, const char* last,
+                                   double& value,  // NOLINT
+                                   chars_format fmt = chars_format::general);
+
+absl::from_chars_result from_chars(const char* first, const char* last,
+                                   float& value,  // NOLINT
+                                   chars_format fmt = chars_format::general);
+
+// std::chars_format is specified as a bitmask type, which means the following
+// operations must be provided:
+inline constexpr chars_format operator&(chars_format lhs, chars_format rhs) {
+  return static_cast<chars_format>(static_cast<int>(lhs) &
+                                   static_cast<int>(rhs));
+}
+inline constexpr chars_format operator|(chars_format lhs, chars_format rhs) {
+  return static_cast<chars_format>(static_cast<int>(lhs) |
+                                   static_cast<int>(rhs));
+}
+inline constexpr chars_format operator^(chars_format lhs, chars_format rhs) {
+  return static_cast<chars_format>(static_cast<int>(lhs) ^
+                                   static_cast<int>(rhs));
+}
+inline constexpr chars_format operator~(chars_format arg) {
+  return static_cast<chars_format>(~static_cast<int>(arg));
+}
+inline chars_format& operator&=(chars_format& lhs, chars_format rhs) {
+  lhs = lhs & rhs;
+  return lhs;
+}
+inline chars_format& operator|=(chars_format& lhs, chars_format rhs) {
+  lhs = lhs | rhs;
+  return lhs;
+}
+inline chars_format& operator^=(chars_format& lhs, chars_format rhs) {
+  lhs = lhs ^ rhs;
+  return lhs;
+}
+
+}  // namespace absl
+
+#endif  // ABSL_STRINGS_CHARCONV_H_