> There is a new form of command substitution that executes the command in

> the current shell execution context. Two forms are implemented: one that

> reads the command substitution's output and another that expects to find

> the result in the REPLY shell variable when the command substitution

> completes.

> New form of command substitution: ${ command; } or ${|command;} to capture

> the output of COMMAND without forking a child process and using pipes

This is awesome. I haven't tested it yet, but if it is what I imagine, it means lots of speed for function/builtin calls.

The REPLY variable comes historically from the `read` command default variable name, so it's familiar for experienced shell users.