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packages/args/CHANGELOG.md

Index: packages/args/CHANGELOG.md
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+## 0.13.2
+
+* Allow option values that look like options. This more closely matches the
+  behavior of [`getopt`][getopt], the *de facto* standard for option parsing.
+
+[getopt]: http://man7.org/linux/man-pages/man3/getopt.3.html
+
+## 0.13.1
+
+* Add `ArgParser.addSeparator()`. Separators allow users to group their options
+  in the usage text.
+
+## 0.13.0
+
+* **Breaking change**: An option that allows multiple values will now
+  automatically split apart comma-separated values. This can be controlled with
+  the `splitCommas` option.
+
+## 0.12.2+6
+
+* Remove the dependency on the `collection` package.
+
+## 0.12.2+5
+
+* Add syntax highlighting to the README.
+
+## 0.12.2+4
+
+* Add an example of using command-line arguments to the README.
+
+## 0.12.2+3
+
+* Fixed implementation of ArgResults.options to really use Iterable<String>
+  instead of Iterable<dynamic> cast to Iterable<String>.
+
+## 0.12.2+2
+
+* Updated dependency constraint on `unittest`.
+
+* Formatted source code.
+
+* Fixed use of deprecated API in example.
+
+## 0.12.2+1
+
+* Fix the built-in `help` command for `CommandRunner`.
+
+## 0.12.2
+
+* Add `CommandRunner` and `Command` classes which make it easy to build a
+  command-based command-line application.
+
+* Add an `ArgResults.arguments` field, which contains the original argument list.
+
+## 0.12.1
+
+* Replace `ArgParser.getUsage()` with `ArgParser.usage`, a getter.
+  `ArgParser.getUsage()` is now deprecated, to be removed in args version 1.0.0.
+
+## 0.12.0+2
+
+* Widen the version constraint on the `collection` package.
+
+## 0.12.0+1
+
+* Remove the documentation link from the pubspec so this is linked to
+  pub.dartlang.org by default.
+
+## 0.12.0
+
+* Removed public constructors for `ArgResults` and `Option`.
+ 
+* `ArgResults.wasParsed()` can be used to determine if an option was actually
+  parsed or the default value is being returned.
+
+* Replaced `isFlag` and `allowMultiple` fields in the `Option` class with a
+  three-value `OptionType` enum.
+  
+* Options may define `valueHelp` which will then be shown in the usage.
+
+## 0.11.0
+
+* Move handling trailing options from `ArgParser.parse()` into `ArgParser`
+  itself. This lets subcommands have different behavior for how they handle
+  trailing options.
+
+## 0.10.0+2
+
+* Usage ignores hidden options when determining column widths.