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Author how to match the '?' character?
dtown22@gmail.com

2007-02-21, 3:58 am

I am very new to perl, and I am trying to figure out how to match a ?,
but i cant seem to figure it out (unless I am doing something else
wrong, which is very possible). Here is my code:

foreach($newBody =~ m/$thread?/isg)

$thread contains a number, which i expect to be followed by a '?'

Basically I want to do something specific for each occurrence,
depending on what else is in the string

but for some reason, this loops more than it should.

If however, i do something like this:

$index = 0;
while($index != -1) {
$index = index($newBody, "$thread?", $index);
}

it loops the correct number of times.

any help is greatly appreciated.

Ani

2007-02-21, 3:58 am

You need to escape the '?' .. like /$thread\?/

- ani

dtown22@gmail.com wrote:
> I am very new to perl, and I am trying to figure out how to match a ?,
> but i cant seem to figure it out (unless I am doing something else
> wrong, which is very possible). Here is my code:
>
> foreach($newBody =~ m/$thread?/isg)
>
> $thread contains a number, which i expect to be followed by a '?'
>
> Basically I want to do something specific for each occurrence,
> depending on what else is in the string
>
> but for some reason, this loops more than it should.
>
> If however, i do something like this:
>
> $index = 0;
> while($index != -1) {
> $index = index($newBody, "$thread?", $index);
> }
>
> it loops the correct number of times.
>
> any help is greatly appreciated.


dtown22@gmail.com

2007-02-21, 6:59 pm

On Feb 21, 1:07 am, "Ani" <call.anir...@gmail.com> wrote:
> You need to escape the '?' .. like /$thread\?/
>
> - ani
>



I thought that might be the case, but I couldn't find any
documentation on special escape characters. Do you happen to know of a
good resource that lists them all?

Uri Guttman

2007-02-21, 6:59 pm

>>>>> "d" == dtown22 <dtown22@gmail.com> writes:

d> On Feb 21, 1:07 am, "Ani" <call.anir...@gmail.com> wrote:[color=darkred]


d> I thought that might be the case, but I couldn't find any
d> documentation on special escape characters. Do you happen to know of a
d> good resource that lists them all?

you obviously didn't read perldoc perlre. perl is very well
documented. if you need more basic regex stuff read perlrequick and
perlretut.

uri

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