cxxopts/CHANGELOG.md

# Changelog

This is the changelog for `cxxopts`, a C++11 library for parsing command line
options. The project adheres to semantic versioning.

## 2.2

### Changed

* Allow integers to have leading zeroes.

### Bug Fixes

* Fix a warning about possible loss of data.

## 2.1.1

### Bug Fixes

* Revert the change adding `const` type for `argv`, because most users expect
  to pass a non-const `argv` from `main`.

## 2.1

### Changed

* Options with implicit arguments now require the `--option=value` form if
  they are to be specified with an option. This is to remove the ambiguity
  when a positional argument could follow an option with an implicit value.
  For example, `--foo value`, where `foo` has an implicit value, will be
  parsed as `--foo=implicit` and a positional argument `value`.
* Boolean values are no longer special, but are just an option with a default
  and implicit value.

### Added

* Added support for `std::optional` as a storage type.
* Allow the help string to be customised.
* Use `const` for the type in the `argv` parameter, since the contents of the
  arguments is never modified.

### Bug Fixes

* Building against GCC 4.9 was broken due to overly strict shadow warnings.
* Fixed an ambiguous overload in the `parse_positional` function when an
  `initializer_list` was directly passed.
* Fixed precedence in the Boolean value regex.

## 2.0

### Changed

* `Options::parse` returns a ParseResult rather than storing the parse
  result internally.
* Options with default values now get counted as appearing once if they
  were not specified by the user.

### Added

* A new `ParseResult` object that is the immutable result of parsing. It
  responds to the same `count` and `operator[]` as `Options` of 1.x did.
* The function `ParseResult::arguments` returns a vector of the parsed
  arguments to iterate through in the order they were provided.
* The symbol `cxxopts::version` for the version of the library.
* Booleans can be specified with various strings and explicitly set false.

## 1.x

The 1.x series was the first major version of the library, with release numbers
starting to follow semantic versioning, after 0.x being unstable.  It never had
a changelog maintained for it. Releases mostly contained bug fixes, with the
occasional feature added.