At 7:12 PM -0800 11/16/11, blawson wrote:
Hi, I'm a newbie to perl and am having trouble with list vs scalar.
There is
an example in Programming Perl where an object is blessed and returned
from its constructor as:
return bless \$value => $class;
I am very unclear what is happening here. The class name is returned
but
exactly how are the $value reference and $class related?
Read the documentation for bless: 'perldoc -f bless'
bless REF,CLASSNAME
bless REF
This function tells the thingy referenced by REF that it is now
an object in the CLASSNAME package. If CLASSNAME is omitted,
the current package is used. Because a "bless" is often the
last thing in a constructor, it returns the reference for
convenience. Always use the two-argument version if a derived
class might inherit the function doing the blessing. See
perltoot and perlobj for more about the blessing (and
blessings) of objects.
The return value of bless is \$value, a reference to the scalar
variable $value. The reference becomes an "object" of class $class.
The '=>' operator is equivalent to a comma. The class name ($class)
is not returned. It is a parameter to the bless operator, which
returns the "blessed" reference value \$value.
See also 'perldoc perltoot' and 'perldoc perlobj' as recommended.
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