CHOMP feature request

So, I have been thinking about it and I'd like to propose
two new features 
with whitespace chomping.  Both of these are low cost to
implement, but do 
add a bit of user convenience.

The first is to add a new chomp type.  Currently CHOMP_ALL
or the '-' modifier 
doesn't really CHOMP_ALL.  It chomps everything on the same
line.  This has 
caused several posts in the short time I've been on the
mailing list.  I'd 
like to see a new chomp type that removes ALL whitespace in
a preceding text 
chunk.  Since CHOMP_ALL is taken I was thinking maybe
CHOMP_KILL, or perhaps 
CHOMP_ALL_NO_REALLY_I_MEAN_ALL, OR CHOMP_DIE_DIE_DIE (But I
would settle for 
CHOMP_KILL).  Logically the constant would take the value of
3 (or I guess 4 
if you want chomp constants to work as a bitset - but I
think that is 
overkill).   To go along with CHOMP_KILL I think that
probably the best 
modifier would be '~'.

So the table would be:

Constant name          Constant Value      Tag Modifier 
CHOMP_NONE           0                             +
CHOMP_ALL               1                             -
CHOMP_COLLAPSE  2                             = # does this
modifier work?
CHOMP_KILL               3                             ~

So CHOMP_KILL would do the following fairly desirable thing
(no hacks 
required).

"
   [%~ 1 %]

             [%~ 2 ~%]

   [% 3 ~%]
"

Which would print 123 without any other whitespace.  Note
that the leading ~ 
on the 1 and the trailing ~ on the 3 do the same thing that
TRIM => 1 would 
do in this case, but would be very different with the
following case.

"      [%~ '    ' ~%]       "

With CHOMP_KILL the final string would be '    ' while with
TRIM => 1 the 
final string would be ''.

Codewise this is very simple to implement in the split_text
method of the 
Template/Parser.pm.  Sorry - no patch at this time.

OK - Request number two.  Can we use the Tag Modifier in
place of the CONSTANT 
name.  Consider:

use Template;
my $t = Template->new(PRE_CHOMP => '-',  POST_CHOMP
=> '~');

As opposed to:

use Template qw(:chomp);
my $t = Template->new(PRE_CHOMP => CHOMP_ALL, 
POST_CHOMP => CHOMP_KILL);

Or in a bad case:

use Template;
my $t = Template->new(PRE_CHOMP => 1,  POST_CHOMP
=> 3);

Allowing the modifier to be used isn't really saving that
much (it isn't that 
hard to import the constants) - but then people would be
less likely to 
hardcode the constants and they wouldn't have to remember
the constant names, 
and if the CHOMP_KILL proposal is accepted - they wouldn't
have to wonder 
which function CHOMP_ALL vs CHOMP_KILL does (which one
really gets rid of 
whitespace vs just the whitespace on the same line).

It also won't be much of a hit to allow the modifier names
as the check only 
needs to happen once at configuration time.

If there are any questions, let me know.  I think these
requests are sane 
enough for most people and won't cause any hardship for
those who don't want 
to use them.

Paul Seamons

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CHOMP feature request

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