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in reply to Re: 'Dynamic scoping' of capture variables ($1, $2, etc.)
in thread 'Dynamic scoping' of capture variables ($1, $2, etc.)

moritz:
Really gotta go now, but just one more experiment: without recursion (actually, along the lines LanX has already posted).

>perl -wMstrict -le "$_ = 'x77x888x1x'; ;; 'zonk' =~ m{(\w+)}xms; ;; print 'before: $1 is ', defined($1) ? qq{'$1'} : 'undefined'; print X1(); print 'after: $1 is ', defined($1) ? qq{'$1'} : 'undefined'; ;; sub X1 { s/(\d+)//; print qq{ '$1'}; return $1 + X2(); } sub X2 { s/(\d+)//; print qq{ '$1'}; return $1 + X3(); } sub X3 { s/(\d+)//; print qq{ '$1'}; return $1; } " before: $1 is 'zonk' '77' '888' '1' 966 after: $1 is 'zonk'

Without recursion, value of $1 seems to be scoped to the subroutine 'block'.
No difference in results for  Xn() + $1 versus  $1 + Xn() or for $1 being undefined initially.