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Postings from April 2005
Juerd wrote: > However, the discussion is about changing these simple, clear, and > useful rules to a more complex situation of choosing a default based on > what the default will be used for, making the default for methods the > invocant rather than $_. I hate those plans and would love to see the > current spec, that is as you decribe above, implemented in the "final" > version. I think your basic error in perception is that $_ is a runtime variable while the invocant(s) are more a design time assumption of what the method is working on. Perl6 has invented the notion of topic as a global lexically scoped variable that is orthogonal to the invocant and non-invocant parameters of (multi) methods. We have two distinct names for these two concepts: $_ and $?SELF. Additional multi method invocants need names anyway. E.g. in methods of GUI classes the invocant would be the selected widget and the topic the event. > (Or well, I believed this was the spec until I tried finding it. I can > find the stuff about .method defaulting to $_ in S12, but $_ being an > alias for the invocant is harder to find.) My reading is that the two concepts have developed concurrently and only recently some pitfalls were identified when they are combined. -- TSa (Thomas Sandlaß)Thread Previous | Thread Next