=head1 NAME Petal::Deprecated - Documents Petal's deprecated syntax. =head1 IMPORTANT NOTE This is an article, not a module. From version 2.00 onwards Petal *requires* that you use well-formed XML. This is because Petal now uses L rather than L and L. In particular, this version of Petal *CAN* break backwards compatibility if you were using Petal's HTML mode will non well formed XHTML. If you still want to use broken XHTML, you can Petal 2.00 in conjunction with L which has been created for this purpose. =head1 INLINE VARIABLES SYNTAX This is the variable 'my_var' : ${my_var}. And if C contained I, Petal would have outputted: This is the variable 'my_var' : Hello World. Now let's say that C is a hash reference as follows: $VAR1 = { hello_world => 'Hello, World' } To output the same result, you would write: This is the variable 'my_var' : ${my_var/hello_world}. =head1 SETTING PETAL OPTIONS AS GLOBALS If you want to use an option throughout your entire program and don't want to have to pass it to the constructor each time, you can set them globally. They will then act as defaults unless you override them in the constructor. $Petal::BASE_DIR (use base_dir option) $Petal::INPUT (use input option) $Petal::OUTPUT (use output option) $Petal::TAINT (use taint option) $Petal::ERROR_ON_UNDEF_VAR (use error_on_undef_var option) $Petal::DISK_CACHE (use disk_cache option) $Petal::MEMORY_CACHE (use memory_cache option) $Petal::MAX_INCLUDES (use max_includes option) $Petal::LANGUAGE (use default_language option) $Petal::DEBUG_DUMP (use debug_dump option) # $Petal::ENCODE_CHARSET (use encode_charset option) -- _DEPRECATED_ $Petal::DECODE_CHARSET (use decode_charset option) =head1 TAL DIRECTIVES ALIASES On top of all that, for people who are lazy at typing the following aliases are provided (although I would recommend sticking to the defaults): * tal:define - tal:def, tal:set * tal:condition - tal:if * tal:repeat - tal:for, tal:loop, tal:foreach * tal:attributes - tal:att, tal:attr, tal:atts * tal:content - tal:inner * tal:replace - tal:outer TRAP: Don't forget that the default prefix is C NOT C, until you set the petal namespace in your HTML or XML document as follows: =head1 XINCLUDES Let's say that your base directory is C, and you're editing C. From there you want to include C =head2 general syntax You can use a subset of the XInclude syntax as follows: For backwards compatibility reasons, you can omit the first slash, i.e. =head2 relative paths If you'd rather use a path which is relative to the template itself rather than the base directory, you can do it but the path MUST start with a dot, i.e. etc. =head2 limitations The C parameter does not support URIs, no other tag than C is supported, and no other directive than the C parameter is supported at the moment. Also note that contrarily to the XInclude specification Petal DOES allow recursive includes up to C<$Petal::MAX_INCLUDES>. This behavior is very useful when templating structures which fit well recursive processing such as trees, nested lists, etc. You can ONLY use the following Petal directives with Xinclude tags: * on-error * define * condition * repeat C, C, C and C are NOT supported in conjunction with XIncludes. =head1 UGLY SYNTAX For certain things which are not doable using TAL you can use what I call the UGLY SYNTAX. The UGLY SYNTAX is UGLY, but it can be handy in some cases. For example consider that you have a list of strings: $my_var = [ 'Foo', 'Bar', 'Baz' ]; $template->process (my_var => $my_var, buz => $buz); And you want to display: Hello : Foo : Bar : Baz Which is not doable with TAL without making the XHTML invalid. With the UGLY SYNTAX you can do: Hello<?for name="string my_var"?> : <?var name="string"?><?end?> Of course you can freely mix the UGLY SYNTAX with other Petal syntaxes. So: <?for name="string my_var"?> $string <?end?> Mind you, if you've managed to read the doc this far I must confess that writing:

$string

instead of:

Dummy

is UGLY too. I would recommend to stick with TAL wherever you can. But let's not disgress too much. =head2 variables Abstract Example <?var name="document/title"?> Why? Because if you don't have things which are replaced by real values in your template, it's probably a static page, not a template... :) =head2 if / else constructs Usual stuff: Happy Birthday, $user/real_name! What?! It's not your birthday? A very merry unbirthday to you! You can use C instead of C, and indeed you can use modifiers: What?! It's not your birthday? A very merry unbirthday to you! Happy Birthday, $user/real_name! Not much else to say! =head2 loops Use either C, C, C or C. They're all the same thing, which one you use is a matter of taste. Again no surprise:

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Variables are scoped inside loops so you don't risk to erase an existing C variable which would be outside the loop. The template engine also provides the following variables for you inside the loop: - iteration number, starting at 0 - iteration number, starting at 1 - is it the first iteration? - is it the last iteration? - is it not the first and not the last iteration? - is the count even? - is the count odd? Again these variables are scoped, you can safely nest loops, ifs etc... as much as you like and everything should be fine. =head2 Includes It will include the file 'include.xml', using the current C<@Petal::BASE_DIR> directory list. If you want use XML::Parser to include files, you should make sure that the included files are valid XML themselves... FYI XML::Parser chokes on this:

foo

bar

But this works:

foo

bar

(Having only one top element is part of the XML spec). =cut