This patchset allows a match expression to have a list of names for its
glob parts, which are assigned to the matched values in the body of the
match.
For example,
```sh
stuff=foobarblahblah/target_{1..30}
for $stuff {
match $it {
*/* as (dir sub) {
echo "doing things with $sub in $dir"
make -C $dir $sub # or whatever...
}
}
}
```
With this, match expressions are now significantly more powerful!