CSS::SAC::LexicalUnit 0.06

CSS::SAC::LexicalUnit is a Perl module that contains SAC units.
SYNOPSIS
use CSS::SAC::LexicalUnit qw(:constants);
foo if $lu->is_type(LU_TYPE_CONSTANT);
In the SAC spec, LexicalUnit is a linked list, that is, you only ever hold one LexicalUnit, and you ask for the next of for the previous one when you want to move on.
Such a model seems awkward, though Im sure it makes sense somehow in Java, likely for a Java-specific reason.
In the Perl implementation, I have changed this. A LexicalUnit is an object that stands on its own and has no next/previous objects. Instead, the $handler->property callback gets called with a LexicalUnitList, which is in fact just an array ref of LexicalUnits.
We also dont differentiate between IntegerValue, FloatValue, and StringValue, its always Value in Perl. This also applies to Parameters and SubValues. Both are called as Value and return an array ref of LexicalUnits.
I added the is_type() method, see CSS::SAC::Condition for advantages of that approach.
CONSTANTS
- ATTR
- CENTIMETER
- COUNTER_FUNCTION
- COUNTERS_FUNCTION
- DEGREE
- DIMENSION
- EM
- EX
- FUNCTION
- GRADIAN
- HERTZ
- IDENT
- INCH
- INHERIT
- INTEGER
- KILOHERTZ
- MILLIMETER
- MILLISECOND
- OPERATOR_COMMA
- OPERATOR_EXP
- OPERATOR_GE
- OPERATOR_GT
- OPERATOR_LE
- OPERATOR_LT
- OPERATOR_MINUS
- OPERATOR_MOD
- OPERATOR_MULTIPLY
- OPERATOR_PLUS
- OPERATOR_SLASH
- OPERATOR_TILDE
- PERCENTAGE
- PICA
- PIXEL
- POINT
- RADIAN
- REAL
- RECT_FUNCTION
- RGBCOLOR
- SECOND
- STRING_VALUE
- SUB_EXPRESSION
- UNICODERANGE
- URI
METHODS
CSS::SAC::LexicalUnit->new($type,$text,$value) or $lu->new($type,$text,$value)
Creates a new unit. The $type must be one of the type constants, the text depends on the type of unit (unit text, func name, etc...), and the value is the content of the lu.
$lu->DimensionUnitText([$dut]) or getDimensionUnitText
get/set the text of the dimension unit (eg cm, px, etc...)
$lu->FunctionName([$fn]) or getFunctionName
get/set the name of the function (eg attr, uri, etc...)
$lu->Value([$value]) or getValue
get/set the value of the lu (which may be another lu, or a lu list)
$lu->LexicalUnitType([$type]) or getLexicalUnitType
get/set the type of the lu
$lu->is_type($lu_constant)
returns true is this lu is of type $lu_constant