tracing 0.1.11

# 0.1.11 (December 20, 2019)

### Added

- `Span::is_none` method (#475)
- `LevelFilter::into_level` method (#470)
- `LevelFilter::from_level` function and `From<Level>` impl (#471)
- Documented minimum supported Rust version (#482)

### Fixed

- Incorrect parameter type to `Span::follows_from` that made it impossible to
  call (#467)
- Missing whitespace in `log` records generated when enabling the `log` feature
  flag (#484)
- Typos and missing links in documentation (#405, #423, #439)

# 0.1.10 (October 23, 2019)

### Added

- Support for destructuring in arguments to `#[instrument]`ed functions (#397)
- Generated field for `self` parameters when `#[instrument]`ing methods (#397)
- Optional `skip` argument to `#[instrument]` for excluding function parameters
  from generated spans (#359)
- Added `dispatcher::set_default` and `subscriber::set_default` APIs, which
  return a drop guard (#388)

### Fixed

- Some minor documentation errors (#356, #370)

# 0.1.9 (September 13, 2019)

### Fixed

- Fixed `#[instrument]`ed async functions not compiling on `nightly-2019-09-11`
  or newer (#342)

### Changed

- Significantly reduced performance impact of skipped spans and events when a
  `Subscriber` is not in use (#326)
- The `log` feature will now only cause `tracing` spans and events to emit log
  records when a `Subscriber` is not in use (#346)

### Added

- Added support for overriding the name of the span generated by `#[instrument]`
  (#330)
- `log-always` feature flag to emit log records even when a `Subscriber` is set
  (#346)

# 0.1.8 (September 3, 2019)

### Changed

- Reorganized and improved API documentation (#317)

### Removed

- Dev-dependencies on `ansi_term` and `humantime` crates, which were used only
  for examples (#316)

# 0.1.7 (August 30, 2019)

### Changed

- New (curly-brace free) event message syntax to place the message in the first
  field rather than the last (#309)

### Fixed

- Fixed a regression causing macro stack exhaustion when the `log` feature flag
  is enabled (#304)

# 0.1.6 (August 20, 2019)

### Added

- `std::error::Error` as a new primitive type (#277)
- Support for mixing key-value fields and `format_args` messages without curly
  braces as delimiters (#288)

### Changed

- `tracing-core` dependency to 0.1.5 (#294)
- `tracing-attributes` dependency to 0.1.2 (#297)

# 0.1.5 (August 9, 2019)

### Added

- Support for `no-std` + `liballoc` (#263)

### Changed

- Using the `#[instrument]` attribute on `async fn`s no longer requires a
  feature flag (#258)

### Fixed

- The `#[instrument]` macro now works on generic functions (#262)

# 0.1.4 (August 8, 2019)

### Added

- `#[instrument]` attribute for automatically adding spans to functions (#253)

# 0.1.3 (July 11, 2019)

### Added

- Log messages when a subscriber indicates that a span has closed, when the
  `log` feature flag is enabled (#180).

### Changed

- `tracing-core` minimum dependency version to 0.1.2 (#174).

### Fixed

- Fixed an issue where event macro invocations with a single field, using local
  variable shorthand, would recur infinitely (#166).
- Fixed uses of deprecated `tracing-core` APIs (#174).

# 0.1.2 (July 6, 2019)

### Added

- `Span::none()` constructor, which does not require metadata and
  returns a completely empty span (#147).
- `Span::current()` function, returning the current span if it is
  known to the subscriber (#148).

### Fixed

- Broken macro imports when used prefixed with `tracing::` (#152).

# 0.1.1 (July 3, 2019)

### Changed

- `cfg_if` dependency to 0.1.9.

### Fixed

- Compilation errors when the `log` feature is enabled (#131).
- Unclear wording and typos in documentation (#124, #128, #142).

# 0.1.0 (June 27, 2019)

- Initial release