-`--enable-help-builtin'
- Include the `help' builtin, which displays help on shell builtins
- and variables.
-
-`--enable-array-variables'
- Include support for one-dimensional array shell variables.
-
-`--enable-dparen-arithmetic'
- Include support for the `ksh' `((...))' command.
-
-`--enable-brace-expansion'
- Include `csh'-like brace expansion ( `b{a,b}c' ==> `bac bbc' ).
-
-`--enable-disabled-builtins'
- Allow builtin commands to be invoked via `builtin xxx' even after
- `xxx' has been disabled using `enable -n xxx'. See *Note Bash
- Builtins::, for details of the `builtin' and `enable' builtin
- commands.
-
-`--enable-command-timing'
- Include support for recognizing `time' as a reserved word and for
- displaying timing statistics for the pipeline following `time'.
- This allows pipelines as well as shell builtins and functions to
- be timed.
-