Re: string escaping in bash

[Pier Paolo Grassi]

the output produced is:

\a
\c\     \e

which seems to me what the OP has asked for

I cannot seem to find in bash the equivalent of (#b) that enables capture
of parenthesized groups within $match array, which is needed for this to
work
there is BASH_REMATCH for the regex match operator =~ but that is not
usable for substitution.
Is there some mean in bash to do string replace with capturing of
subpatterns?

Pier Paolo Grassi


Il giorno ven 12 mar 2021 alle ore 23:14 Alex fxmbsw7 Ratchev <
fxmbsw7@gmail.com> ha scritto:

> i think that also suffers the bugs i had, but not sure
>
> On Fri, Mar 12, 2021 at 11:07 PM Pier Paolo Grassi <pierpaolog@gmail.com>
> wrote:
>
>> In zsh this could be solved like this:
>>
>> local -A conversions=(n $'\n' t $'\t' \\ \\)
>> example='\a\n\c\\\t\e'
>> echo -E - ${example//(#b)\\(?)/${conversions[$match[1]]:-\\$match[1]}}
>>
>> but I don't know if this can be expressed with bash syntax, maybe someone
>> can help me translate it?
>>
>> Pier Paolo Grassi
>>
>>
>> Il giorno ven 12 mar 2021 alle ore 22:48 Alex fxmbsw7 Ratchev <
>> fxmbsw7@gmail.com> ha scritto:
>>
>>> i think i cannot succeed
>>> the most was the v=nonexist// version
>>>
>>> thank you
>>>
>>> On Fri, Mar 12, 2021 at 10:41 PM Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com
>>> >
>>> wrote:
>>>
>>> > thank you
>>> >
>>> > i may post a new version soon whenever i succeed it, i just gotta think
>>> > more about it
>>> >
>>> > thank you again
>>> >
>>> > On Fri, Mar 12, 2021 at 10:37 PM Lawrence Velázquez <vq@larryv.me>
>>> wrote:
>>> >
>>> >> > On Mar 12, 2021, at 3:25 PM, Alex fxmbsw7 Ratchev <
>>> fxmbsw7@gmail.com>
>>> >> wrote:
>>> >> >
>>> >> > this is without keep over and does the stupid non edge cases
>>> >> > maybe you can give me better test cases ?
>>> >> >
>>> >> > i=-1 res=( ) list=( '\one' '\\Two' '\\\Three' '\\\\four'
>>> '\\\\\five' )
>>> >> > right=( '\one' '\Two' '\\Three' '\\four' '\\\five' ) ; for str in
>>> >> > "${list[@]}" ; do str=${str//\\n/$'\n'} str=${str//\\t/$'\t'}
>>> >> > res[++i]=${str//\\\\/\\} ; printf '%d %s %s\n' $i "${res[i]}"
>>> >> "${right[i]}"
>>> >> > ; done
>>> >>
>>> >>         bash-5.1$ str='\\n'
>>> >>         bash-5.1$ printf '%s' "$str" | od -A n -t a -t x1
>>> >>                    \   \   n
>>> >>                    5c  5c  6e
>>> >>
>>> >> This should become '\n' (0x5c 0x6e).
>>> >>
>>> >>         bash-5.1$ str=${str//\\n/$'\n'}
>>> >>         bash-5.1$ str=${str//\\t/$'\t'}
>>> >>         bash-5.1$ str=${str//\\\\/\\}
>>> >>         bash-5.1$ printf '%s' "$str" | od -A n -t a -t x1
>>> >>                    \  nl
>>> >>                    5c  0a
>>> >>
>>> >> --
>>> >> vq
>>> >>
>>> >>
>>>
>>