Need help with expect (tcl) regular expression

Ray Muforosky

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Jul 12, 2006, 11:55:40 AM7/12/06

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I'm having problem tracking this string "VXUJT-12#" . it could be any 2
digit number ending with a pound sign ( a dash followed by 2 digits and
a #). I need help catching it using -re:

expect {
-re {(*\-\d\d\#$)} { break}
"invalid input" { puts "Wrong input"; exit}
}

Thanks in advance for your help.

Jonathan Bromley

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Jul 12, 2006, 12:00:33 PM7/12/06

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On 12 Jul 2006 08:55:40 -0700, Ray
Muforosky <muf...@gmail.com> wrote:

> -re {(*\-\d\d\#$)} { break}

I suspect you meant (.*-\d\d\#$)

In an RE, "*" on its own just means "one asterisk". And unless I'm
mistaken, you don't need to escape the hyphen.
--
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Michael A. Cleverly

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Jul 12, 2006, 1:17:59 PM7/12/06

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On Wed, 12 Jul 2006, Jonathan Bromley wrote:

> On 12 Jul 2006 08:55:40 -0700, Ray
> Muforosky <muf...@gmail.com> wrote:
>
> > -re {(*\-\d\d\#$)} { break}
>
> I suspect you meant (.*-\d\d\#$)
>
> In an RE, "*" on its own just means "one asterisk". And unless I'm
> mistaken, you don't need to escape the hyphen.

Actually * means zero to many of the preceeding atom. In this case there
isn't one and the regexp won't even compile:

% regexp {(*\-\d\d\#$)} foo-42#
couldn't compile regular expression pattern: quantifier operand invalid

Michael

Jonathan Bromley

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Jul 12, 2006, 1:24:23 PM7/12/06

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On Wed, 12 Jul 2006 11:17:59 -0600, "Michael A. Cleverly"
<mic...@cleverly.com> wrote:

>On Wed, 12 Jul 2006, Jonathan Bromley wrote:

>> In an RE, "*" on its own just means "one asterisk".

No, it doesn't...

>Actually * means zero to many of the preceeding atom.

Indeed it does. Blush. Blame old age.

At least my fix was right ;-)

ms

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Jul 13, 2006, 4:02:32 PM7/13/06

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>>> -re {(*\-\d\d\#$)} { break}
>>
>>I suspect you meant (.*-\d\d\#$)
>>
>>In an RE, "*" on its own just means "one asterisk". And unless I'm
>>mistaken, you don't need to escape the hyphen.
>
>
> Actually * means zero to many of the preceeding atom. In this case there
> isn't one and the regexp won't even compile:
>
> % regexp {(*\-\d\d\#$)} foo-42#
> couldn't compile regular expression pattern: quantifier operand invalid
>
> Michael

What about:
-re ".*-\[0-9\]\[0-9\]#$" { ...

or even
-re "\[A-Z\]+-\[0-9\]\[0-9\]#$" { ...

second regular if only we expected upper characters like "VXUJT-12#".

But I have a question, because I noticed that you used regular like
"\d", is it mean digit ? Which version of regular is able to work with it?

Regards
Sebastian

Bruce Hartweg

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Jul 13, 2006, 5:02:06 PM7/13/06

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ms wrote:

> But I have a question, because I noticed that you used regular like
> "\d", is it mean digit ? Which version of regular is able to work with it?
>

yes it does, there are numerous shorthand escapes which are all documented
on the re_syntax man page in the ESCAPES section
http://www.tcl.tk/man/tcl8.4/TclCmd/re_syntax.htm#M28
These arrived in 8.1 if I recall correctly

Bruce

ms

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Jul 13, 2006, 5:39:04 PM7/13/06

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>>
> yes it does, there are numerous shorthand escapes which are all documented
> on the re_syntax man page in the ESCAPES section
> http://www.tcl.tk/man/tcl8.4/TclCmd/re_syntax.htm#M28
> These arrived in 8.1 if I recall correctly
>
> Bruce

Thanks a lot for answer and link. It will check my view at re from now.

Sebastian