Dunno about Raku but I already talked here about this BS in PHP. (AFAIK they've corrected the documentation in the meantime.)

The term stems IIRC from Lisp was popularized in Scheme and means a "hull" structure containing a sub plus bound lexical variables.

Not sure if other languages also implement this with lex-pads like Perl does. (See e.g. PadWalker)

PS: I'm happy to see that these videos initiate discussions. :)

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

Update

see also WP:Closure (computer programming)

In reply to Re^2: Yet Another Program on Closures ~ Steven Lembark ~ TPRC 2025 - YouTube by LanX
in thread Yet Another Program on Closures ~ Steven Lembark ~ TPRC 2025 - YouTube by LanX

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