preg_match_all optional subpattern

[Han]

Using preg_match_all, I need to capture a list of first and last names plus
an optional country code proceeding them.

For example:

<tr><td>AU</td><td>Jane Smith</td></tr>
<tr><td></td><td>Bill Johnson</td></tr>
<tr><td>GB</td><td>Larry Brown</td></tr>
<tr><td>US</td><td>Mary Jordon</td></tr>
<tr><td></td><td>Peter Jones</td></tr>

The country code might exist, it might not.

I would like the array contents to look like this:

AU Jane Smith
Bill Johnson
US Larry Brown
GB Mary Jordon
Peter Jones

I know a subpattern is needed of all the possible country codes:

AU|GB|US

but how do you include this as an optional subpattern?

Thanks in advance.

[John Dunlop]

Han wrote:

Using preg_match_all, I need to capture a list of first and last names plus
an optional country code proceeding them.

For example:

<tr><td>AU</td><td>Jane Smith</td></tr>
<tr><td></td><td>Bill Johnson</td></tr>
<tr><td>GB</td><td>Larry Brown</td></tr>
<tr><td>US</td><td>Mary Jordon</td></tr>
<tr><td></td><td>Peter Jones</td></tr>

[...] I know a subpattern is needed of all the possible country codes:

AU|GB|US

but how do you include this as an optional subpattern?

The ? quantifier means zero or one of whatever came before,
representable by {0,1}. Quantifying a subpattern using the
question mark denotes its nonobligatory nature.

So, to match optional two-letter country codes within a table cell
(doesn't properly cater for attributes, but that's rectifiable):

`<td.*>([a-z]{2})?</td.*>`Usi

If you wish to list the possible values, precluding others:

`<td.*>(au|gb|u s)?</td.*>`Usi

--
Jock

[s van gemmert]

"Han" <no****@nowhere .com> wrote in message news:<TT******* *************@r wcrnsc51.ops.as p.att.net>...

Using preg_match_all, I need to capture a list of first and last names plus
an optional country code proceeding them.

For example:

<tr><td>AU</td><td>Jane Smith</td></tr>
<tr><td></td><td>Bill Johnson</td></tr>
<tr><td>GB</td><td>Larry Brown</td></tr>
<tr><td>US</td><td>Mary Jordon</td></tr>
<tr><td></td><td>Peter Jones</td></tr>

The country code might exist, it might not.

I would like the array contents to look like this:

AU Jane Smith
Bill Johnson
US Larry Brown
GB Mary Jordon
Peter Jones

I know a subpattern is needed of all the possible country codes:

AU|GB|US
this pattern should do the job:

"{<tr><td>\ s*([A-Z]{2})?\s*</td><td>\s*(\w+) ?\s*(\w+)\s*</td></tr>}im"

if this pattern is used in preg_match_all, it should produce the
desired result.
it will extract the country code if availible, first name if
availible, and last name.
They will be put in an 2 dim array. If no country code or first name
is given, the array element will be left empty.

hope this helps,

sascha

but how do you include this as an optional subpattern?

Thanks in advance.

[Han]

John,

Thank you for another detailed reply.

The cryptic syntax is beginning to slowly sink in, but there's still a few
nagging issues.

In my price list, the amount may or may not be preceded with a $ sign.

For instance, the list might look like this:

$2.99
1.99
$3.00
$4.00

I modified my price pattern to accommodate this:

((\\$|\s*)?\d{1 ,3}\.\d{2})

which works great. The problem is, it also creates another array dimension
that contains only $ or space:

$

$
$

I can simply ignore this dimension, but is there a way to prevent it?

Thanks (again) in advance.

"John Dunlop" <jo*********@jo hndunlop.info> wrote in message
news:MP******** *************** *@news.freeserv e.net...

Han wrote:

Using preg_match_all, I need to capture a list of first and last names plus an optional country code proceeding them.

For example:

<tr><td>AU</td><td>Jane Smith</td></tr>
<tr><td></td><td>Bill Johnson</td></tr>
<tr><td>GB</td><td>Larry Brown</td></tr>
<tr><td>US</td><td>Mary Jordon</td></tr>
<tr><td></td><td>Peter Jones</td></tr>

[...] I know a subpattern is needed of all the possible country codes:

AU|GB|US

but how do you include this as an optional subpattern?

The ? quantifier means zero or one of whatever came before,
representable by {0,1}. Quantifying a subpattern using the
question mark denotes its nonobligatory nature.

So, to match optional two-letter country codes within a table cell
(doesn't properly cater for attributes, but that's rectifiable):

`<td.*>([a-z]{2})?</td.*>`Usi

If you wish to list the possible values, precluding others:

`<td.*>(au|gb|u s)?</td.*>`Usi

--
Jock

[John Dunlop]

Han wrote:

((\\$|\s*)?\d{1 ,3}\.\d{2})

which works great. The problem is, it also creates another array
dimension that contains only $ or space:

[...] I can simply ignore this dimension, but is there a way to
prevent it?

Subpatterns that begin with the two character sequence "?:" aren't
captured. You could then write your pattern as:

`(?:\\$|\s*)?\d {1,3}\.\d{2}`

--
Jock

[Han]

Jock,

That's it--thanks.

I've been spending some time re-reading the pattern documentation on php.net
and it's beginning to sink in.

Again, much appreciated!

"John Dunlop" <jo*********@jo hndunlop.info> wrote in message
news:MP******** *************** *@news.freeserv e.net...

Han wrote:

((\\$|\s*)?\d{1 ,3}\.\d{2})

which works great. The problem is, it also creates another array
dimension that contains only $ or space:

[...] I can simply ignore this dimension, but is there a way to
prevent it?

Subpatterns that begin with the two character sequence "?:" aren't
captured. You could then write your pattern as:

`(?:\\$|\s*)?\d {1,3}\.\d{2}`

--
Jock