It works like a normal pattern rule,
```
../%/.clone :
    [ -d $(@D) ] || git clone ${GIT_HOME}/$* $(@D)/
    touch $@
```
But it will only match the targets listed before the first colon.
```
${DMD_DIR}/.clone ${DRUNTIME_DIR}/.clone ${PHOBOS_DIR}/.clone
```
We could simply go with `../%/.clone :` if that's OK for you.