Note that ;$ doesn't parse the same as a builtin like uc: 
$ perl -we'print uc 1, 2'
12

$ perl -we'sub myuc(;$) { $_[0]||$_ } print myuc 1, 2'
Too many arguments for main::myuc at -e line 1, at EOF

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Also, in the presence of my $_, myuc won't be able to see the right $_. Implementing a _ prototype is on the todo list, but not on any particular person's plate that I know of.

In reply to Re^2: subroutine bewilderment: how to mimic builtins by ysth
in thread subroutine bewilderment: how to mimic builtins by dimar

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