That's not better than a myriad validator routines all slightly different?

No. The validation is applied only to the value, and only where required.

If I defined a 'string-that-can-only-contain-uppercase' type and a 'string-that-can-only-contain-decimal-digits' type and then later want to join my userids with their respective phone numbers for display, I have a type clash.

This is conflating type validation with value validation.

Traits

How do traits validate an lvalue assignment to a partital field.

eg. substr( $x, $start, $length ) = $str;

tieing

How does STORE gain access to the lvalue selection criteria from the lvalue sub call?

Same example. How do I know at STORE time, what part of the string is affected?

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.

In reply to Re^9: Assignable Subroutines by BrowserUk
in thread Assignable Subroutines by dragonchild

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