Re^3: Recap: The Future of Perl 5

[RonW]

I agree, your proposed syntax is much nicer.

I did see somethings surprising.

In:

class Point {
    has Num ($x, $y);
    
    method inverted () {
        return Point->new( x => $y, y => $x );
    }
}

you have $x instead of $self->x (likewise for $y).

I found this surprising, and had to pause to think for a second or 2. How common is it in other OO languages to not need "self" to reference instance variables in instance methods? Personally, I don't recall ever seeing it done without "self". (Been so long since I last used C++ that I had forgotten.)

More surprising was:

class Cache::LRU {
    use Hash::Ordered;
    our      $num_caches = 0;                    # class data (unused 
+in this example)
    my       $x          = Hash::Ordered->new;   # private instance da
+ta
    has UInt $max_size   = 20;                   # public instance dat
+a

    method set ( Str $key, $value ) {
        if ( $x->exists($key) ) {
            $x->delete($key);

where $x is also an instance variable.

(Just some additional thoughts.)

[Ovid]

I found this surprising, and had to pause to think for a second or 2. How common is it in other OO languages to not need "self" to reference instance variables in instance methods? Personally, I don't recall ever seeing it done without "self". (Been so long since I last used C++ that I had forgotten.)

Java does this too. You can disambiguate (if you have a local variable of the same name), with this. For example, this.x.

[LanX]

IIRC is Ruby using sigils for @instance and @@class variables..

Python has self, JS has this.

But JS is setting this implicitly, i.e. it's not the first argument like self in Python and Perl.

You could mimic the semantics of JS and Ruby with closure variables holding references...

update

added references

update

PHP seems to have an implicit $this.

[tobyink]

Yep, PHP has an implicit $this, and also has self which refers to the current class (not object).