On 2/15/23 2:52 AM, Koichi Murase wrote:
two or three command substitutions are generally not considered "so
many command substitutions".
I can't reproduce a great deal of unresponsiveness with five or six
either, and my computer is very old too. I think this "delay" you
mentioned has more to do with the commands being substituted than bash.
You might hear of Fish shell is good, but which part of Fish shell is
considered good? They are just good for interactive behaviors. When we
focus on the language design, Fish shell is actually worse than Bash.
It's all about priorities; if your top priority is fashionable prompt
strings, you won't mind the inferior language.
Of course, there is no case where ${ list; } is "absolutely
necessary". But in that logic, the shell functions are not "absolutely
necessary", and even the command substitutions are not "absolutely
necessary" as everything can be in principle processed in combinations
of pipelines and { list; }, etc.
But they benefit the user tremendously.
OK, I understand what you try to say, (though I regard "no one ever"
and "any sense" as exaggerations; at least the developer who
introduced the feature should have had the reasoning and also should
have used it.
The developer doesn't count as an organic user. And ksh93 has been
around for three decades; if there were demand for the feature in
question, other shells would have copied it already.
I still think it benefits the users, even though it can be thought of
kind of syntax sugar for `list > tmp; var=$(< tmp)' (as managing the
temporary files properly is usually.non-trivial).
How many forks does that avoid anyway? Let's be realistic, the overhead
from one fork is not enough to warrant new syntax.
