need help with concantenation

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks,
For the life of me I cannot concantenate these two variables.
"$month_3_tables" a Literal variable ..$x an Incremented variable inside of a for loop.

for($x=0;$x<$how_many_items;$x++){

   if($item eq "March") {($month_3_tables.$x) .= "<tr> <td width='106'
+ height='24' valign='top'>$field_vals[0]</td> <td width='39' height='
+24' valign='top'>$field_vals[1]</td> <td width='590' height='24' vali
+gn='top'>$field_vals[6]</td>  </tr>"}
}
[download]

Thanks

Comment on need help with concantenation Download Code

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Re: need help with concantenation by seattlejohn (Deacon) on Jan 12, 2003 at 06:26 UTC
Without any surrounding context it's hard to determine what you're trying to accomplish here. Consider that `$x .= $y` is just shorthand for `$x = $x . $y`. So what you've written is this: `$month_3_tables . $x = $month_3_tables . $x . "html stuff"` [download] which isn't meaningful, as you need to have a single variable name on the left side of the assignment statement. Is your intent to modify individual elements within an array, like this? `$month_3_tables[$x] .= "html stuff"` [download] It might help if you followed up with a bigger snippet of code and/or a more complete explanation of what you expected the behavior to be. $perlmonks{seattlejohn} = 'John Clyman';	[reply] [d/l] [select]
Re: need help with concantenation by Coruscate (Sexton) on Jan 12, 2003 at 09:58 UTC
The following snippet is what you want to use here (assuming I understand what you are trying to accomplish): `my @month_3_tables; for my $x (0 .. $how_many_items) { if ($item eq "March") { push @month_3_tables, "<tr>.....</tr>"; } }` [download] Note that my example uses a programmer-friendly version of the for{} loop. Also, I'm not sure if you're using an if() statement for every month, but if not, then using push() to add an item to an array is much more efficient than trying to name variables such as $month_3_tables0, $month_3_tables1, $month_3_table2, etc, etc. `($month_3_tables.$x) .= "..."` The above line that you have within your program is invalid perl, as has already been stated within another reply to your post. Perl just doesn't work that way for creating variables. Technically, you could use the following line to replace yours: `${$month_3_tables . $x} = "<tr>...</tr>";` But that is just not the best way to go about this. Use an array, since this is the exact reason they were created :)	[reply] [d/l] [select]


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