Re: new user questions and issues

[ZyX <kp-pav@yandex.ru>]

About local: instead of setting an option it looks like you can use

    typeset +g _t3

(`typeset +g`, `typeset` and `local` are almost equivalent, but typeset without any flags listed in documentation exhibits the same behaviour as `local`). Specifically in the example you can use

    local _t3=XXX__${_t2}__

: when there is an assignment `local` will not print previous value.



08.05.2015, 00:47, "Kannan Varadhan" <kvaradhan3@gmail.com>:
> Thank you Eric.
>
> I had worked out other ways of achieving #1, just wanted to learn if there was a good way to do it.
>
> The others, I get.
>
> Thanks,
>
> Kannan
>>  On May 6, 2015, at 1:50 PM, Eric Cook <llua@gmx.com> wrote:
>>
>>  I can snipe the easier to explain ones.
>>  On 05/06/2015 01:37 PM, Kannan Varadhan wrote:
>>>  Issue #1:  Programmatic Scripting, how to?
>>>
>>>  I would like to do the following:
>>>
>>>  for var in path infopath manpath cdpath ; do
>>>     typeset -agU $var
>>>     local capsvar
>>>     capsvar=$(echo $var | tr 'a-z' 'A-Z')
>>>     $var=( $(echo ${$capsvar} | sed 's/:/ /g') )
>>>  done
>>>
>>>  But this does not work, because ${$capsvar}  gets me a zsh: bad substitution.
>>>  Is there any way to achieve this in zsh?
>>  You can use the parameter expansion flag P. ''${(P)capsvar}''
>>
>>  With the exception of infopath, The arrays you are trying to define are
>>  already created and tied to the uppercase scalar parameters.
>>  Any change made to one is reflected in the other.
>>
>>  echo by default interprets c string escapes, you can disable that with
>>  the -E option.
>>
>>  You could avoid the command substitution with the parameter expansion
>>  flag U ''capsvar=${(U)var}'' to change the case of the value.
>>
>>  $var=(...) is also an error. ''set -A $var element1 element2 ...'' will
>>  allow you to indirectly set arrays
>>>  Issue #2.  Overridden local variables get echoed?
>>>
>>>  ~ 5% cat lib/zsh/test2                                                  9:55:52
>>>  function test2
>>>     print why is the previous value echoed when a local variable is 'overridden?'
>>  It actually happens when you use typeset, local, etc. on a parameter
>>  that is already defined. You can use the option TYPESET_SILENT option to
>>  silence it.
>>
>>  from the typeset section of zshbuiltins(1):
>>  If  the  shell  option  TYPESET_SILENT  is  not  set, for each remaining
>>  name that refers to a parameter that is set, the name and value of the
>>  parameter are printed in the form of an assignment.  Nothing is printed
>>  for newly-created parameters, or when any attribute flags listed below
>>  are given along with the name.  Using `+' instead of minus to introduce
>>  an attribute turns it off.
>>
>>  Pretty sure #3 and #4 is due to how typeset creates a local parameters
>>  when used in a function. So typeset -U PATH create a new parameter
>>  without a value, with the -U attribute.