Say, with zsh one can prefix a command with noglob to "turn off filename generation (globbing)".
I'm looking for a shell where similar approach can be used to disable not only globbing but all kind of expansions. Rationale: Using backslash escaping or quotes for any complex command turns it into a bloody mess which is A) difficult to read and comprehend B) unsuitable for re-use on the other levels of nesting.
In zsh, you can do:
set -o interactive_comments -o extendedglob
alias '@=:;# '
handle_@() {
local match
if [[ $1 = (#b)@\##[[:space:]]##([^[:space:]]##)[[:space:]]#(*) ]] $match
}
preexec_functions+=(handle_@)
And then prefix your commands with @ (has to make up the whole editing buffer, no foo; @ cmd nor foo | @ cmd, etc) for the first word after that to be taken as the command name, and the rest of the line to be passed as one single argument to that command:
$ @ echo asd'@123 # # qwe $x ``
asd'@123 # # qwe $x ``
That means that one argument can't start with whitespace nor contain newline characters though.
That works by aliasing @ with :;#, the : noop command (so preexec hooks be run) followed by the comment leader, so the rest of the line is parsed as a comment and discarded.
In the preexec hook, we split that unprocessed line (in $1) into the command and arg. Note the \## to allow # after @ in there to work around in bug in older versions of zsh (5.3 or older). Note that it won't work in 4.3.12 (from 2011) or older where the comment is not included in prexec()'s $1.
Of interest, zsh also has the quote-region and quote-line widgets (bound to Alt+" and Alt+' respectively by default in emacs mode) which can save the hassle of do proper quoting by yourself.
For, instance, you could do:
$ perl -e Ctrl+Space$x = 'whatever';...Alt+"
Where Ctrl+Space or Ctrl+@ (upon which terminals usually send a NUL character), sets the start of the region.
Upon Alt+", that would be transformed to:
perl -e '$x = '\''whatever'\'';...'
with the region now quoted. See also https://stackoverflow.com/q/5407916 for how to set the region (selection) with Shift + arrow/motion keys.
zsh -f?
undo though, and writing an unquote widget wouldn't be so hard using the Q parameter expansion flag. You've also yet to show an example of the kind of mess you want to avoid. I've never felt this kind of need in the 25+ years I've been using shells on a daily basis.
handle_@ still doesn't work for you (or whoever upvoted your comment above) in zsh -f, can you please indicate what you see after entering functions -t handle_@ and then @ echo ;#$', and which version of zsh you're using?