String literals with the prefix `u8` now have the type `const char8_t[N]` in
C++20. As a consequence the library does not compile in c++2a mode with GCC
(you can't concatenate `std::basic_string<char>` and `const char8_t[]` as
`char` and `char8_t` are different types).
Fixes#132. Since the map of options is shared between Options and
ParseResult, they should use a shared pointer instead of a reference so
that ParseResult can be returned without referencing destroyed memory.
Fixes#109. Although we always used numbers in the ASCII range, it was
in a `size_t`, leading to a warning about possible loss of data on some
compilers.
Fixes#102. Don't show the default value when it is a boolean and the
value is false. Note that this is a bit of a hack and the
implementation should probably be reevaluated in the future.
Fixes#96. Default values of options not specified on the command line
had a `count` of 1. It would be better if they had a count of 0 because
they were not actually specified, so that count is only for options
given by the user.
* `|` should be inside of `(…)`
It's possible to use `(t|true|T|True)` as `truthy_pattern` but still failing `true` as a truthy under my environment :-(
```
Apple LLVM version 8.0.0 (clang-800.0.42.1)
Target: x86_64-apple-darwin15.6.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
```
Fixes#83.
Adds an overload for positional arguments taking a
`std::initializer_list`. When using an `initializer_list` with one
argument, the function call is ambiguous matching both `std::string`
and `std::vector<std::string>`.
Fixes#84. Implicit values are not handled very well. For example:
--foo false true
--foo --bar
In the first, `false` is an argument to `--foo`, and then `true` is a
positional argument. In the second, because of the hyphen in `--bar`, `--foo`
is parsed with its implicit value. This seems inconsistent and unintuitive.
Better is that implicit values *never* consume the next parameter to be
completely consistent. This means that values with an implicit parameter
*must* be specified using the `--option=value` form.
The parsing for boolean options was broken by 6c9bae4a07 which added implicit
and default values, and the ability to parse boolean strings. Having an option
after the boolean tried to parse that into the boolean instead of as a
positional parameter.
See #84 for the bug report.
It appears that the `libc++` available on Ubuntu 14.04 is broken and
doesn't handle the boolean regex correctly. Newer versions appear to be
correct but I have to work out how to get 14.04 to use it.
