What's wrong with this expression?

What's wrong with this expression?

[Daniel Serodio (lists)]

I'm trying to troubleshoot a script that works with bash but fails with 
zsh, and it uses the "regex match" operator. What's wrong with this 
expression?

     [[ "foo" ~= "x" ]] && echo true

Fails with "zsh: condition expected: ~="

Thanks in advance,
Daniel Serodio

Re: What's wrong with this expression?

[Dan Nelson]

In the last episode (Oct 17), Daniel Serodio (lists) said:
> I'm trying to troubleshoot a script that works with bash but fails with 
> zsh, and it uses the "regex match" operator. What's wrong with this 
> expression?
> 
>      [[ "foo" ~= "x" ]] && echo true
> 
> Fails with "zsh: condition expected: ~="

Try with =~ instead.  Your line fails on bash as well:

$ [[ "foo" ~= "x" ]] && echo true
bash: conditional binary operator expected
bash: syntax error near `~='

-- 
	Dan Nelson
	dnelson@allantgroup.com

Re: What's wrong with this expression?

[Mikael Magnusson]

On 17 October 2011 23:09, Daniel Serodio (lists)
<daniel.lists@mandic.com.br> wrote:
> I'm trying to troubleshoot a script that works with bash but fails with zsh,
> and it uses the "regex match" operator. What's wrong with this expression?
>
>    [[ "foo" ~= "x" ]] && echo true
>
> Fails with "zsh: condition expected: ~="

You wrote ~= instead of =~

-- 
Mikael Magnusson

Re: What's wrong with this expression?

[Daniel Serodio (lists)]

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Mikael Magnusson wrote:
> On 17 October 2011 23:09, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br>  wrote:
>> I'm trying to troubleshoot a script that works with bash but fails with zsh,
>> and it uses the "regex match" operator. What's wrong with this expression?
>>
>>     [[ "foo" ~= "x" ]]&&  echo true
>>
>> Fails with "zsh: condition expected: ~="
>
> You wrote ~= instead of =~
>
Ooops. Error copy'n'pasting. The actual line in the script that fails is:

     if [[ ! "${PATH}" =~ $regex ]] ; then

where "regexp" is:

      regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"

Thanks again,
Daniel Serodio

Re: What's wrong with this expression?

[Mikael Magnusson]

On 17 October 2011 23:27, Daniel Serodio (lists)
<daniel.lists@mandic.com.br> wrote:
> Mikael Magnusson wrote:
>
> On 17 October 2011 23:09, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br> wrote:
>
> I'm trying to troubleshoot a script that works with bash but fails with zsh,
> and it uses the "regex match" operator. What's wrong with this expression?
>
>    [[ "foo" ~= "x" ]] && echo true
>
> Fails with "zsh: condition expected: ~="
>
> You wrote ~= instead of =~
>
> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
>
>     if [[ ! "${PATH}" =~ $regex ]] ; then
>
> where "regexp" is:
>
>      regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"

Fails how?

-- 
Mikael Magnusson

Re: What's wrong with this expression?

[Daniel Serodio (lists)]

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Mikael Magnusson wrote:
> On 17 October 2011 23:27, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br>  wrote:
>> Mikael Magnusson wrote:
>>
>> On 17 October 2011 23:09, Daniel Serodio (lists)
>> <daniel.lists@mandic.com.br>  wrote:
>>
>> I'm trying to troubleshoot a script that works with bash but fails with zsh,
>> and it uses the "regex match" operator. What's wrong with this expression?
>>
>>     [[ "foo" ~= "x" ]]&&  echo true
>>
>> Fails with "zsh: condition expected: ~="
>>
>> You wrote ~= instead of =~
>>
>> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
>>
>>      if [[ ! "${PATH}" =~ $regex ]] ; then
>>
>> where "regexp" is:
>>
>>       regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"
>
> Fails how?
>
Sorry. Fails with "condition expected: =~"

Re: What's wrong with this expression?

[Mikael Magnusson]

On 17 October 2011 23:31, Daniel Serodio (lists)
<daniel.lists@mandic.com.br> wrote:
> Mikael Magnusson wrote:
>
> On 17 October 2011 23:27, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br> wrote:
>
> Mikael Magnusson wrote:
>
> On 17 October 2011 23:09, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br> wrote:
>
> I'm trying to troubleshoot a script that works with bash but fails with zsh,
> and it uses the "regex match" operator. What's wrong with this expression?
>
>    [[ "foo" ~= "x" ]] && echo true
>
> Fails with "zsh: condition expected: ~="
>
> You wrote ~= instead of =~
>
> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
>
>     if [[ ! "${PATH}" =~ $regex ]] ; then
>
> where "regexp" is:
>
>      regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"
>
> Fails how?
>
> Sorry. Fails with "condition expected: =~"

Maybe you don't have any regex module installed/loaded, does
-regex-match instead of =~ work?

-- 
Mikael Magnusson

Re: What's wrong with this expression?

[Daniel Serodio (lists)]

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Mikael Magnusson wrote:
> On 17 October 2011 23:31, Daniel Serodio (lists)
> <daniel.lists@mandic.com.br>  wrote:
>> Mikael Magnusson wrote:
>>
>> On 17 October 2011 23:27, Daniel Serodio (lists)
>> <daniel.lists@mandic.com.br>  wrote:
>>
>> Mikael Magnusson wrote:
>>
>> On 17 October 2011 23:09, Daniel Serodio (lists)
>> <daniel.lists@mandic.com.br>  wrote:
>>
>> I'm trying to troubleshoot a script that works with bash but fails with zsh,
>> and it uses the "regex match" operator. What's wrong with this expression?
>>
>>     [[ "foo" ~= "x" ]]&&  echo true
>>
>> Fails with "zsh: condition expected: ~="
>>
>> You wrote ~= instead of =~
>>
>> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
>>
>>      if [[ ! "${PATH}" =~ $regex ]] ; then
>>
>> where "regexp" is:
>>
>>       regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"
>>
>> Fails how?
>>
>> Sorry. Fails with "condition expected: =~"
>
> Maybe you don't have any regex module installed/loaded, does
> -regex-match instead of =~ work?
Hmmm, this seems to be the problem.

     [[ "foo" -regex-match "x" ]] && echo x

fails with:

     zsh: unrecognized condition: `foo'

Re: What's wrong with this expression?

[Phil Pennock]

On 2011-10-17 at 19:27 -0200, Daniel Serodio (lists) wrote:
> Mikael Magnusson wrote:
> > On 17 October 2011 23:09, Daniel Serodio (lists)
> >>     [[ "foo" ~= "x" ]]&&  echo true

> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
> 
>      if [[ ! "${PATH}" =~ $regex ]] ; then

See, this is why reporting the _actual_ code which causes an error
helps; or, if you want to simplify, at least test that the failure still
happens with the simplified version.

This was a bug, fixed on 2010-10-10 and the fix included in the release
of zsh 4.3.11.  The current version of zsh is 4.3.12.  Negated patterns
and tests combined with &&/|| failed prior to that when using the =~
operator.

If you are running 4.3.11 or newer, please state which version you're
using and preferably show the minimum needed to reproduce, starting from
"zsh -f".

Re: What's wrong with this expression?

[Benjamin R. Haskell]

On Mon, 17 Oct 2011, Daniel Serodio (lists) wrote:

> Mikael Magnusson wrote:
>> On 17 October 2011 23:09, Daniel Serodio (lists) wrote:
>>> I'm trying to troubleshoot a script that works with bash but fails 
>>> with zsh,
>>> [...]
>
> [...]
>
>    if [[ ! "${PATH}" =~ $regex ]] ; then
>
> where "regexp" is:
>
>     regex="^([^:]*:)*${rvm_bin_path}(:[^:]*)*$"

When first trying to set up rvm, it regularly segfaulted on me in 
zsh-4.3.10.  I initially narrowed the problem down to the __rvm_after_cd 
function, and just gutted it by adding:

[[ -n "$ZSH_VERSION" ]] && return 0

as line 9 of ~/.rvm/scripts/cd

Then at least it sometimes worked.  But, shortly thereafter, I just 
updated Zsh to zsh-4.3.12, and haven't had problems since.

-- 
Best,
Ben

Re: What's wrong with this expression?

[Daniel Serodio (lists)]

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Phil Pennock wrote:
> On 2011-10-17 at 19:27 -0200, Daniel Serodio (lists) wrote:
>> Mikael Magnusson wrote:
>>> On 17 October 2011 23:09, Daniel Serodio (lists)
>>>>      [[ "foo" ~= "x" ]]&&   echo true
>
>> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
>>
>>       if [[ ! "${PATH}" =~ $regex ]] ; then
>
> See, this is why reporting the _actual_ code which causes an error
> helps; or, if you want to simplify, at least test that the failure still
> happens with the simplified version.
Mea culpa indeed. I tried to simplify the problem but ended up 
complicating it.
> This was a bug, fixed on 2010-10-10 and the fix included in the release
> of zsh 4.3.11.  The current version of zsh is 4.3.12.  Negated patterns
> and tests combined with&&/|| failed prior to that when using the =~
> operator.
>
> If you are running 4.3.11 or newer, please state which version you're
> using and preferably show the minimum needed to reproduce, starting from
> "zsh -f".
Thanks a lot. This computer is running zsh 4.2.6, I'll try to have it 
updated.

Regrards,
Daniel Serodio

Re: What's wrong with this expression?

[Phil Pennock]

On 2011-10-18 at 11:08 -0200, Daniel Serodio (lists) wrote:
> >> Ooops. Error copy'n'pasting. The actual line in the script that fails is:
> >>
> >>       if [[ ! "${PATH}" =~ $regex ]] ; then

> Thanks a lot. This computer is running zsh 4.2.6, I'll try to have it 
> updated.

4.2.6 does not have the =~ operator.

=~ was added on 2007-05-01, when Peter applied my patch (I'm the one who
made the mistake which led to ! not working right).  The first release
of zsh with this in was 4.3.5, released on or around 2008-02-01.

zsh 4.2.6 was released on or around 2005-12-03.

Try using -pcre-match instead -- zsh has had PCRE regex support for a
long time, it's only the =~ support and the zsh/regex for using the
system POSIX regexp libraries for extended regexps that were new with
4.3.5.

For those versions of zsh with =~ support, it does extended regexps by
default, unless you setopt REMATCH_PCRE.  Anything which is a valid
extended regexp pattern is likely to be a valid PCRE regexp (but not
the other way around).  "man pcrepattern" for more details.

if [[ ! "${PATH}" -pcre-match $regex ]]; then
  # ...
fi

-Phil