Johannes Schindelin <Johannes.Schindelin@xxxxxx> writes: > Sharp eyes, and a *very* good point. The double space is actually required > for this patch to work as intended. I added the following explanation to > the commit message: > > Note that `$(ALL_COMMANDS)` starts with a space, and that is rather > crucial for the `while read how cmd` loop: some of the input lines do > not actually have the form `<how> <cmd>`, but only `<cmd>`, therefore > `$cmd` evaluates to the empty string, and when we are looking for > `* $cmd *` in ` $(ALL_COMMANDS)`, we do find it because the latter > starts with a double space. > In other words, the double space helps us skip the lines that list > only a command. That sounds more like a bug in the existing set-up even before your patch (in fact, these lines are probably from 2007 or so, long before you started touching our top-level Makefile heavily). If we want to ignore lines with only one token, I'd rather see it explicitly done, e.g. ... generate data ... | while read how cmd do # skip a line with a single token case "$cmd" in "") continue ;; esac # is $cmd part of the known command list? case " $(ALL_COMMANDS) " in *" $cmd "*) ;; # skip *) echo ... warning ... ;; esac done instead of relying on "if $cmd is empty, then SP + $cmd + SP makes double space, so let's have double space somewhere in the list of known commands" cuteness. Thanks.
