HTML::Tiny - Lightweight, dependency free HTML/XML generation
This document describes HTML::Tiny version 1.01
use HTML::Tiny;
my $h = HTML::Tiny->new;
# Generate a simple page
print $h->html(
[
$h->head( $h->title( 'Sample page' ) ),
$h->body(
[
$h->h1( { class => 'main' }, 'Sample page' ),
$h->p( 'Hello, World', { class => 'detail' }, 'Second para' )
]
)
]
);
# Outputs
<html>
<head>
<title>Sample page</title>
</head>
<body>
<h1 class="main">Sample page</h1>
<p>Hello, World</p>
<p class="detail">Second para</p>
</body>
</html>
HTML::Tiny is a simple, dependency free module for
generating HTML (and XML). It concentrates on generating
syntactically correct XHTML using a simple Perl notation.
In addition to the HTML generation functions utility functions are provided to
new
HTML::Tiny. No arguments
tag( $name, ... )
Returns HTML (or XML) that encloses each of the arguments in the specified tag. For example
print $h->tag('p', 'Hello', 'World');
would print
<p>Hello</p><p>World</p>
notice that each argument is individually wrapped in the specified tag. To avoid this multiple arguments can be grouped in an anonymous array:
print $h->tag('p', ['Hello', 'World']);
would print
<p>HelloWorld</p>
The [ and ] can be thought of as grouping a number of arguments.
Attributes may be supplied by including an anonymous hash in the argument list:
print $h->tag('p', { class => 'normal' }, 'Foo');
would print
<p class="normal">Foo</p>
Attribute values will be HTML entity encoded as necessary.
Multiple hashes may be supplied in which case they will be merged:
print $h->tag('p',
{ class => 'normal' }, 'Bar',
{ style => 'color: red' }, 'Bang!'
);
would print
<p class="normal">Bar</p><p class="normal" style="color: red">Bang!</p>
Notice that the class="normal" attribute is merged with the style attribute for the second paragraph.
To remove an attribute set its value to undef:
print $h->tag('p',
{ class => 'normal' }, 'Bar',
{ class => undef }, 'Bang!'
);
would print
<p class="normal">Bar</p><p>Bang!</p>
An empty attribute - such as 'checked' in a checkbox can be encoded by passing an empty array reference:
print $h->closed( 'input', { type => 'checkbox', checked => [] } );
would print
<input checked type="checkbox" />
Return Value
In a scalar context tag returns a string. In a list context it
returns an array each element of which corresponds to one of the
original arguments:
my @html = $h->tag('p', 'this', 'that');
would return
@html = (
'<p>this</p>',
'<p>that</p>'
);
That means that when you nest calls to tag (or the equivalent HTML aliases - see below) the individual arguments to the inner call will be tagged separately by each enclosing call. In practice this means that
print $h->tag('p', $h->tag('b', 'Foo', 'Bar'));
would print
<p><b>Foo</b></p><p><b>Bar</b></p>
You can modify this behavior by grouping multiple args in an anonymous array:
print $h->tag('p', [ $h->tag('b', 'Foo', 'Bar') ] );
would print
<p><b>Foo</b><b>Bar</b></p>
This behaviour is powerful but can take a little time to master. If you imagine '[' and ']' preventing the propagation of the 'tag individual items' behaviour it might help visualise how it works.
Here's an HTML table (using the tag-name convenience methods - see below) that demonstrates it in more detail:
print $h->table(
[
$h->tr(
[ $h->th( 'Name', 'Score', 'Position' ) ],
[ $h->td( 'Therese', 90, 1 ) ],
[ $h->td( 'Chrissie', 85, 2 ) ],
[ $h->td( 'Andy', 50, 3 ) ]
)
]
);
which would print the unformatted version of:
<table>
<tr><th>Name</th><th>Score</th><th>Position</th></tr>
<tr><td>Therese</td><td>90</td><td>1</td></tr>
<tr><td>Chrissie</td><td>85</td><td>2</td></tr>
<tr><td>Andy</td><td>50</td><td>3</td></tr>
</table>
Note how you don't need a td() for every cell or a tr() for every row. Notice also how the square brackets around the rows prevent tr() from wrapping each individual cell.
Often when generating nested HTML you will find yourself writing corresponding nested calls to HTML generation methods. The table generation code above is an example of this.
If you prefer these nested method calls can be deferred like this:
print $h->table(
[
\'tr',
[ \'th', 'Name', 'Score', 'Position' ],
[ \'td', 'Therese', 90, 1 ],
[ \'td', 'Chrissie', 85, 2 ],
[ \'td', 'Andy', 50, 3 ]
]
);
In general a nested call like
$h->method( args )
may be rewritten like this
[ \'method', args ]
This allows complex HTML to be expressed as a pure data structure. See
the stringify method for more information.
open( $name, ... )
Generate an opening HTML or XML tag. For example:
print $h->open('marker');
would print
<marker>
Attributes can be provided in the form of anonymous hashes in the same way as for tag. For example:
print $h->open('marker', { lat => 57.0, lon => -2 });
would print
<marker lat="57.0" lon="-2">
As for tag multiple attribute hash references will be merged. The example above could be written:
print $h->open('marker', { lat => 57.0 }, { lon => -2 });
close( $name )
Generate a closing HTML or XML tag. For example:
print $h->close('marker');
would print:
</marker>
closed( $name, ... )
Generate a closed HTML or XML tag. For example
print $h->closed('marker');
would print:
<marker />
As for tag and open attributes may be provided as hash references:
print $h->closed('marker', { lat => 57.0 }, { lon => -2 });
would print:
<marker lat="57.0" lon="-2" />
auto_tag( $name, ... )
Calls either tag or closed based on built in rules
for the tag. Used internally to implement the tag-named methods.
stringify( $obj )
Called internally to obtain string representations of values.
It also implements the deferred method call notation (mentioned above) so that
my $table = $h->table(
[
$h->tr(
[ $h->th( 'Name', 'Score', 'Position' ) ],
[ $h->td( 'Therese', 90, 1 ) ],
[ $h->td( 'Chrissie', 85, 2 ) ],
[ $h->td( 'Andy', 50, 3 ) ]
)
]
);
may also be written like this:
my $table = $h->stringify(
[
\'table',
[
\'tr',
[ \'th', 'Name', 'Score', 'Position' ],
[ \'td', 'Therese', 90, 1 ],
[ \'td', 'Chrissie', 85, 2 ],
[ \'td', 'Andy', 50, 3 ]
]
]
);
Any reference to an array whose first element is a reference to a scalar
[ \'methodname', args ]
is executed as a call to the named method with the specified args.
In addition to the methods described above HTML::Tiny provides
all of the following HTML generation methods:
a abbr acronym address area b base bdo big blockquote body br
button caption cite code col colgroup dd del div dfn dl dt em
fieldset form frame frameset h1 h2 h3 h4 h5 h6 head hr html i
iframe img input ins kbd label legend li link map meta noframes
noscript object ol optgroup option p param pre q samp script select
small span strong style sub sup table tbody td textarea tfoot th
thead title tr tt ul var
The following methods generate closed XHTML (<br />) tags by default:
area base br col frame hr img input meta param
So:
print $h->br; # prints <br />
print $h->input({ name => 'field1' });
# prints <input name="field1" />
print $h->img({ src => 'pic.jpg' });
# prints <img src="pic.jpg" />
All other tag methods generate tags to wrap whatever content they are passed:
print $h->p('Hello, World');
prints:
<p>Hello, World</p>
So the following are equivalent:
print $h->a({ href => 'http://hexten.net' }, 'Hexten');
and
print $h->tag('a', { href => 'http://hexten.net' }, 'Hexten');
url_encode( $str )
URL encode a string. Spaces become '+' and non-alphanumeric characters are encoded as '%' + their hexadecimal character code.
$h->url_encode( ' <hello> ' ) # returns '+%3chello%3e+' =cut
sub url_encode { my $str = $_[0]->stringify( $_[1] ); $str =~ s/([^A-Za-z0-9_~])/$1 eq ' ' ? '+' : sprintf("%%%02x", ord($1))/eg; return $str; }
url_decode( $str )
URL decode a string. Reverses the effect of url_encode.
$h->url_decode( '+%3chello%3e+' ) # returns ' <hello> '
query_encode( $hash_ref )
Generate a query string from an anonymous hash of key, value pairs:
print $h->query_encode({ a => 1, b => 2 })
would print
a=1&b=2
entity_encode( $str )
Encode the characters '<', '>', '&', '\'' and '"' as their HTML entity equivalents:
print $h->entity_encode( '<>\'"&' );
would print:
<>'"&
json_encode
Encode a data structure in JSON (Javascript) format:
print $h->json_encode( { ar => [ 1, 2, 3, { a => 1, b => 2 } ] } );
would print:
{"ar":[1,2,3,{"a":1,"b":2}]}
Because JSON is valid Javascript this method can be useful when generating ad-hoc Javascript. For example
my $some_perl_data = {
score => 45,
name => 'Fred',
history => [ 32, 37, 41, 45 ]
};
# Transfer value to Javascript
print $h->script( { type => 'text/javascript' },
"\nvar someVar = " . $h->json_encode( $some_perl_data ) . ";\n " );
# Prints
# <script type="text/javascript">
# var someVar = {"history":[32,37,41,45],"name":"Fred","score":45};
# </script>
An HTML::Tiny is a blessed hash ref.
validate_tag( $closed, $name, $attr )
validate_tag to throw an error or issue a warning when an
attempt is made to generate an invalid tag.
HTML::Tiny requires no configuration files or environment variables.
By design HTML::Tiny has no non-core dependencies.
To run the tests you will require Test::More.
None reported.
No bugs have been reported.
Please report any bugs or feature requests to
bug-html-tiny@rt.cpan.org, or through the web interface at
http://rt.cpan.org.
Andy Armstrong <andy@hexten.net>
Aristotle Pagaltzis <pagaltzis@gmx.de>
Copyright (c) 2007, Andy Armstrong <andy@hexten.net>. All
rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.
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