Export of internal Abseil changes

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24162e64040e89f174531fa78fc0ff43c3a67da4 by Abseil Team <absl-team@google.com>:

Make ABSL_RETIRED_FLAG behave consistently with ABSL_FLAG.

Before the change:
ABSL_RETIRED_FLAG does not compile when there are competing ctors in the type, even when ABSL_FLAG does.

After the change:
ABSL_RETIRED_FLAG compiles when ABSL_FLAG does.

PiperOrigin-RevId: 286437395

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870d4cb4d114813e9cefe30d26d020b0fdcdc4b4 by Tom Manshreck <shreck@google.com>:

Add docs on bind_front

PiperOrigin-RevId: 286433540

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b0c328bd9bb64e0382f942f93b85054229dafeac by Tom Manshreck <shreck@google.com>:

Specify the format for LogSeverity flags

PiperOrigin-RevId: 286402811
GitOrigin-RevId: 24162e64040e89f174531fa78fc0ff43c3a67da4
Change-Id: I89785145d049fee49c6b9cf3357893ece9a6231c
This commit is contained in:
Abseil Team 2019-12-19 12:03:35 -08:00 committed by CJ Johnson
parent 7bd1935dcb
commit ad904b6cd3
5 changed files with 127 additions and 34 deletions

View file

@ -24,19 +24,45 @@
namespace absl {
ABSL_NAMESPACE_BEGIN
// Four severity levels are defined. Logging APIs should terminate the program
// absl::LogSeverity
//
// Four severity levels are defined. Logging APIs should terminate the program
// when a message is logged at severity `kFatal`; the other levels have no
// special semantics.
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag` overload be declared and defined
// in the flags module rather than here. The `AbslUnparseFlag` overload is
// defined there too for consistency.
// Values other than the four defined levels (e.g. produced by `static_cast`)
// are valid, but their semantics when passed to a function, macro, or flag
// depend on the function, macro, or flag. The usual behavior is to normalize
// such values to a defined severity level, however in some cases values other
// than the defined levels are useful for comparison.
//
// The parser accepts arbitrary integers (as if the type were `int`). It also
// accepts each named enumerator, without regard for case, with or without the
// leading 'k'. For example: "kInfo", "INFO", and "info" all parse to the value
// `absl::LogSeverity::kInfo`.
// Exmaple:
//
// // Effectively disables all logging:
// SetMinLogLevel(static_cast<absl::LogSeverity>(100));
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag()` overload be declared and
// defined in the flags library itself rather than here. The `AbslUnparseFlag()`
// overload is defined there as well for consistency.
//
// absl::LogSeverity Flag String Representation
//
// An `absl::LogSeverity` has a string representation used for parsing
// command-line flags based on the enumerator name (e.g. `kFatal`) or
// its unprefixed name (without the `k`) in any case-insensitive form. (E.g.
// "FATAL", "fatal" or "Fatal" are all valid.) Unparsing such flags produces an
// unprefixed string representation in all caps (e.g. "FATAL") or an integer.
//
// Additionally, the parser accepts arbitrary integers (as if the type were
// `int`).
//
// Examples:
//
// --my_log_level=kInfo
// --my_log_level=INFO
// --my_log_level=info
// --my_log_level=0
//
// Unparsing a flag produces the same result as `absl::LogSeverityName()` for
// the standard levels and a base-ten integer otherwise.
@ -47,6 +73,8 @@ enum class LogSeverity : int {
kFatal = 3,
};
// LogSeverities()
//
// Returns an iterable of all standard `absl::LogSeverity` values, ordered from
// least to most severe.
constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
@ -54,6 +82,8 @@ constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
}
// LogSeverityName()
//
// Returns the all-caps string representation (e.g. "INFO") of the specified
// severity level if it is one of the standard levels and "UNKNOWN" otherwise.
constexpr const char* LogSeverityName(absl::LogSeverity s) {
@ -66,6 +96,8 @@ constexpr const char* LogSeverityName(absl::LogSeverity s) {
: s == absl::LogSeverity::kFatal ? "FATAL" : "UNKNOWN";
}
// NormalizeLogSeverity()
//
// Values less than `kInfo` normalize to `kInfo`; values greater than `kFatal`
// normalize to `kError` (**NOT** `kFatal`).
constexpr absl::LogSeverity NormalizeLogSeverity(absl::LogSeverity s) {
@ -77,6 +109,8 @@ constexpr absl::LogSeverity NormalizeLogSeverity(int s) {
return absl::NormalizeLogSeverity(static_cast<absl::LogSeverity>(s));
}
// operator<<
//
// The exact representation of a streamed `absl::LogSeverity` is deliberately
// unspecified; do not rely on it.
std::ostream& operator<<(std::ostream& os, absl::LogSeverity s);