Re: triviality regarding $# counts

[Ray Andrews <rayandrews@eastlink.ca>]

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> I dunno.  I've lost the example that I saved. Never mind, I'll keep an eye on it, and figure out next time. Red herring for now.  It's a bit confusing looking into typeset -p output. All this 'splitting' stuff is not simple. For now everything works and I'm quite sure it's a bit more orthodox.
>
>     
A script:
---------------------------------------------------------------------------------

redline () { echo -e "$red$@$nrm" }

typeset -ga aaa=("
abc

     def ghi
     jkl mno

     pqr
")

redline "\naaa:"
print -l $aaa
redline "\naaa[1]:"
print -l $aaa[1]
redline "linecount of aaa is: $#aaa ... Single element!"

ccc=( ${(@f)aaa} )

redline '\nccc=( ${(@f)aaa} )'
print -l $ccc
redline "linecount of ccc is: $#ccc ... split, but blank lines gone."

ddd=( "${(@f)aaa}" )

redline '\nddd=( "${(@f)aaa}" ) ... it seems like a lot of trouble to 
copy the array as it is.'
print -l "$ddd[@]"  #... don't forget the quotes, idiot!"
redline "linecount of ddd is: $#ddd ... split, but blanks preserved and 
counted. NB EIGHT NOT SIX!"

redline "\nddd[1]: That's right it's blank, just as it should be."
print -l $ddd[1]
redline "\nddd[2]:"
print -l $ddd[2]

redline "And now the typesets\n"
typeset -p aaa
typeset -p ccc
typeset -p ddd

# Verbatim:

# typeset -a aaa=( $'\nabc\n\n\tdef ghi\n\tjkl mno\n\n\tpqr\n' )
# typeset -a ccc=( abc $'\tdef ghi' $'\tjkl mno' $'\tpqr' )
# typeset -a ddd=( '' abc '' $'\tdef ghi' $'\tjkl mno' '' $'\tpqr' '' )

# Aligned: Note the steeenking dollars ;-) ... and how they seem to 
replace the newlines. No?

# typeset -a aaa=( $'\nabc  \n\n\tdef ghi  \n\tjkl mno \n\n\tpqr\n' 
)     #Original with blanks
# typeset -a ccc=(     abc    $'\tdef ghi' $'\tjkl mno   ' $'\tpqr' )  
          #No blanks.
# typeset -a ddd=(  '' abc '' $'\tdef ghi' $'\tjkl mno' '' $'\tpqr' '' 
)    #Blanks retained BUT not the same structure!

-----------------------------------------------------------------------------------

... so what about the dollars?

Anyway, it comes clear: '${(@f)....}' doesn't ADD (or retain) newlines 
it removes them!  (Tho splitting the array where they used to be.) 
Doesn't need them cuz elements aren't separated by newlines (like I 
thought) but by ... however it's done.  Single quotes indicate 
elements.  And, best of all, copying an array, blanks and all, (not 
shown above) turns out to be simple:

eee=( $aaa ) and:

eee=( "{$(@f)aaa}" )

... turns out to be a false equivalence where newlines are REMOVED. 
Don't be fooled by 'printf' -- it might not show you the genuine state 
of the array.  Scalars show their blank lines automatically but we need:

print -l -- "$eee[@]"

... with arrays.  Trust typedef -p.


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