comment on

If your strings are stand-alone, then using anchors (\A & \Z (or ^ & $ unless your using the /m option)) will work fine, but if your trying to detect matches for this regex within the context of a larger string, then you can acheive this using a few zero-width assertions.

#! perl -slw
use strict;

while( <DATA> ) {
    chomp;
    print if m[
        \bC                     # Starting with C preceeded by a non-\
+w char
        (?:                     # and either
            800                 # 800
            |                   # or
            (?: 29 | 35 )       # 29 or 35
            (?:                 # and
                (?: 50(?!XL) )  # 50 not followed by XL
                |               # or
                (?: 00XL )      # 00XL
            )
        )\b                     # followed by a word break
    ]x;
}
__DATA__
This  is the spec for the ABC800. This device is a
This  is the spec for the C800. This device is a
This  is the spec for the C2900. This device is a
This  is the spec for the C2950. This device is a
This  is the spec for the C2900XL. This device is a
This  is the spec for the C2950XL. This device is a
This  is the spec for the C3500. This device is a
This  is the spec for the C3550. This device is a
This  is the spec for the C3500XL. This device is a
This  is the spec for the C3500XLM. This device is a
This  is the spec for the C3550XL. This device is a

__OUTPUT__
D:\Perl\test>junk
This  is the spec for the C800. This device is a
This  is the spec for the C2950. This device is a
This  is the spec for the C2900XL. This device is a
This  is the spec for the C3550. This device is a
This  is the spec for the C3500XL. This device is a
[download]

Examine what is said, not who speaks.

"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller

In reply to Re: A question of 'or' in a Regex by BrowserUk
in thread A question of 'or' in a Regex by c

Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
Want more info? How to link or How to display code and escape characters are good places to start.


Do you know where your variables are?
	PerlMonks