Re: [feature request] parameter transformation to safely add strings to PS1, &c.

[Alex fxmbsw7 Ratchev]

a bit better

~ $ a=( \' \\ \$var $'\e[1m' ) ps='$ ' ; printf -v q %q\  "${a[@]}" ;
ps+=$q ; printf %s\\n "$ps"
$ \' \\ \$var $'\E[1m'

On Mon, Aug 23, 2021, 00:50 Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com> wrote:

> oh indeed it doesnt do what you want
> maybe printf %q does
> sorry
>
> On Mon, Aug 23, 2021, 00:45 Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
> wrote:
>
>> i meant this with removing quotes
>>
>> ~ $ shopt -s extglob ; a=( . a \' \$var $'\e[1m' ) ps='$ ' a=(
>> "${a[@]@Q}" ) ; for i in ${!a[@]} ; do a[i]=${a[i]#?(\$)\'} a[i]=${a[i]%\'}
>> ; done ; ps+=${a[*]} ; printf %s\\n "$ps"
>> $ . a \ $var \E[1m
>> ~ $
>>
>> On Mon, Aug 23, 2021, 00:02 Emanuele Torre <torreemanuele6@gmail.com>
>> wrote:
>>
>>> Emanuele Torre <torreemanuele6@gmail.com> wrote:
>>> >   ~ --${@Q}-> '~' --${#\'}-> ~' --${%\'}-> ~
>>>
>>> Sorry, that was a bad example. Still, it does not accomplish anything:
>>>
>>>   \w --${@Q}-> '\w' --${#\'}-> \w' --${%\'}-> \w
>>>
>>> On Sun, 22 Aug 2021 at 23:56, Emanuele Torre <torreemanuele6@gmail.com>
>>> wrote:
>>> >
>>> > Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com> wrote:
>>> > > and renoving the beginning and ending ' s
>>> >
>>> > even if you remove the first and last ':
>>> > 1) that is 3 PEs as the solution i described (${a//\\/\\\\}
>>> > ${a//\`/\\\`} ${a//$/\\$} vs ${a@Q} ${a#\'} ${a%\'} )
>>> > 2) it doesn't actually accomplish anything:
>>> >
>>> >   ~ --${@Q}-> '~' --${#\'}-> ~' --${%\'}-> ~
>>> >
>>> > On Sun, 22 Aug 2021 at 23:14, Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
>>> wrote:
>>> > >
>>> > > what about @Q
>>> > > and renoving the beginning and ending ' s
>>> > >
>>> > >
>>> > > On Sun, Aug 22, 2021, 23:13 Emanuele Torre <torreemanuele6@gmail.com>
>>> wrote:
>>> > >>
>>> > >> It would be nice to have a parameter transformation (e.g. "${par@p
>>> }")
>>> > >> that expands $par to a string that will not be expanded by PS1,
>>> PS2, &c.
>>> > >>
>>> > >> example:
>>> > >>
>>> > >>   tmp_var=$(blabla) # this variable will not exist when PS1 is
>>> expanded
>>> > >>   PS1="blabla ${tmp_var@p} blabla"
>>> > >>
>>> > >> I think a valid way to achieve the same behaviour in the currenct
>>> > >> version of bash:
>>> > >>
>>> > >>   tmp_var=$(blabla)
>>> > >>   tmp_var=${tmp_var//\\/\\\\}
>>> > >>   tmp_var=${tmp_var//\`/\\\`}
>>> > >>   tmp_var=${tmp_var//$/\\$}
>>> > >>   PS1="blabla $tmp_var blabla"
>>> > >>
>>> > >> But a parameter transformation would be nicer.
>>> > >>
>>> > >> This parameter transformation should also make sure to not cause an
>>> > >> expansion when concatenated.
>>> > >>
>>> > >>   var='$'
>>> > >>   printf '%s\n' "${var@p}" # should not expand to `$'.
>>> > >>   PS1="${var@P}(date)" # because this should expand to `$(date)'
>>> > >>                        # and not to the output of `date'.
>>> > >>
>>> > >> Cheers,
>>> > >>   emanuele6
>>> > >>
>>>
>>