Re: bug with chpwd/allexport (plus expansion/substitution remarks)

["Bart Schaefer" <schaefer@xxxxxxxxxxxxxxxx>]

On Aug 15,  8:25am, TGAPE! wrote:
} Subject: Re: bug with chpwd/allexport (plus expansion/substitution remarks
}
} I know this was a while ago, but I frequently lack time...

I know what you mean.

} Bart Schaefer wrote:
} > On Jul 17,  2:42pm, Zefram wrote:
} >} Dominik Vogt wrote:
} >}>                        BTW if the second workaround you suggest works,
} >}>then it is a bug. The manpage states clearly, that a local variable is
} >}>still exported if the ALLEXPORT option is set and the variable was
} >}>prviously unset.
} >} 
} >} But with `local', the variable disappears at the end of the function,
} > 
} > That also doesn't affect whether the name is added to the named directory
} > hash table.  Unsetting the variable doesn't unhash the name; making it a
} > local has no effect on this problem whatsoever.
} 
} It doesn't?  It seems to in 3.1.1

Indeed, to say "no effect whatsoever" is an overstatement; I was misled by
performing my tests with a variable that already had a value.  Here's the
actual situation:

IF a variable is already set to a name that begins with a slash AND THEN
a local of the same name is added to the named directory hash table, the
result is that the original variable remains in the directory hash table
after the function exits.  Otherwise, unset of a variable including of a
local on exit from the function, removes the corresponding hash entry.

There's a slight difference between 3.0.5 and 3.1.4 in the handling of an
unset local, illustrated below.

I originally tried only the equivalent of namedir4 in test 2, which caused
me to make the overstatement excerpted above.

Test functions:

    namedir1 () {
	setopt localoptions autonamedirs
	local $1=$2
	echo namedir1: $(hash -d | grep \^$1)
    }
    namedir2 () {
    	local $1=$2
	namedir1 $1 $2
	echo namedir2: $(hash -d | grep \^$1)
    }
    namedir3 () {
        local $1
    	unset $1
	namedir1 $1 $2
	echo namedir3: $(hash -d | grep \^$1)
    }
    namedir4 () {
	namedir1 $1 $2
	echo namedir4: $(hash -d | grep \^$1)
    }
    namedir_test () {
	echo $ZSH_NAME $ZSH_VERSION
	unset test1
	test2=/usr/bin
	echo TEST 1
	namedir1 test1 /etc
	namedir2 test1 /etc
	namedir3 test1 /etc
	namedir4 test1 /etc
	echo TEST 2
	namedir1 test2 /etc
	namedir2 test2 /etc
	namedir3 test2 /etc
	namedir4 test2 /etc
    }

Results with zsh -f:

zagzig% namedir_test
zsh 3.0.5-extended
TEST 1
namedir1: test1=/etc
namedir1: test1=/etc
namedir2: test1=/etc
namedir1: test1=/etc
namedir3:
namedir1: test1=/etc
namedir4:
TEST 2
namedir1: test2=/etc
namedir1: test2=/etc
namedir2: test2=/etc
namedir1: test2=/etc
namedir3:
namedir1: test2=/etc
namedir4: test2=/usr/bin

zagzig% namedir_test
zsh 3.1.4
TEST 1
namedir1: test1=/etc
namedir1: test1=/etc
namedir2: test1=/etc
namedir1: test1=/etc
namedir3:
namedir1: test1=/etc
namedir4:
TEST 2
namedir1: test2=/etc
namedir1: test2=/etc
namedir2: test2=/etc
namedir1: test2=/etc
namedir3: test2=/usr/bin
namedir1: test2=/etc
namedir4: test2=/usr/bin

Note the difference in the handling of "local" in the namedir3 test from
3.0.5 to 3.1.4.  I tend to doubt that this discrepancy is intentional.

} Besides, it certainly seems to me that it should; if a variable doesn't
} exist, how can a reference to that variable be valid?  (Yeah, I know
} hashes aren't references to variables, even with autonamedirs, but I'm
} trying to look at this from the user's perspective.)

I agree with you.


-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com