Re: Inconsistencies in "-quoting and @-splitting, could someone elaborate?

[Sebastian Gniazdowski <sgniazdowski@gmail.com>]

On Sun, 28 Oct 2018 at 12:54, Sebastian Gniazdowski
<sgniazdowski@gmail.com> wrote:
> Despite array is single element, @ splits it into array type. (s::)
> and (z) behave differently for single-element result, that is one
> (maybe subjective) inconsistency, and for the second – @ doesn't help
> (ie. (z@) still doesn't return as an array), that's second
> inconsistency IMO.

I've forgot one inconsistency and thought that a more explicit
description of them (of the (subjective) inconsistencies) can be
provided:

1.a) array=( "foo" ); print "${#${(@)array}}" -> 1
1.b) words="singleword"; print "${#${(z)words}}" -> 10
1.description) with @, it is possible to obtain "always-array"
behavior, while (z) and (s::) have exceptions and not always return
arrays (one could think that if a flag takes the responsibility for
splitting in string-context ("-quoted), then that it will mimic the
first tool to do that, the @)

2.a) the same as 1.a
2.b) words="singleword"; print "${#${(z@)words}}" -> 10
2.description) if ${(@)array} makes single-element quoted array back
an array again, then shouldn't @ acting on single-element data (Bart
said it's not array) returned by (z)/(s::) also make it an array
again?

3.a) array=( "foo" "bar" ); print -rl "$array" -> foo bar # both
elements in one line, signaling the expected "scalarization"
3.b) words="two words"; print -rl "${(z)words}" -> foo\nbar # two
lines, with one word each, indicating non-scalar result
3.c) words="two words"; print -rl "${(s: :)words}" -> foo\nbar # --- " ---
3.description) Basically, the general method of Zshell to obtain
scalars with no splits – double-quoting – isn't followed by (z) and
(s::) flags. The manuals often elaborate about some situations and
"-quoting like if this would be a general "scalarization" method
guaranteed by Zsh design. Hard to give examples, but maybe this one:

    ${name:|arrayname}
              ... If the substitution is scalar, either because
              name is a scalar variable >>or the expression is
quoted<<, the elements of arrayname are instead  tested
              against the entire expression.

Above slightly suggests "-quoting as a general method for obtaining scalars.
-- 
Sebastian Gniazdowski
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