thx, ikegami these are pretty much all the tests I already ran. 8-|

I think it's an old optimization feature that got dropped/lost, without updating the docs.

If anyone has access to a fairly old perl5 version, it would be nice to know what these test produce... He doesn't need to use B::Concise, it's documented that redefining a "constant function" always has to give a warning!

so plz, just run this code, and check for a warning:

no warnings;

my $lex = 4;         # file scoped lexical

#--- normal
# inner scope
sub with_proto ()  { my $lex }

# outer scope
{
  my $lex = 4; 
  sub with_proto() { $lex } 
}

# file scope
sub with_proto()  { $lex }

#--- reference
# inner scope
sub with_proto()  {\ my $lex }

# outer scope
{
  my $lex = 4; 
  sub with_proto() {\ $lex } 
}

# file scope
sub with_proto()  {\ $lex }


#------ lvalue

#--- normal
# inner scope
sub with_proto() :lvalue { my $lex }

# outer scope
{
  my $lex = 4; 
  sub with_proto() :lvalue { $lex } 
}

# file scope
sub with_proto() :lvalue { $lex }

#--- reference
# lvalue references are not feasible, because of
#   "Can't modify single ref constructor in lvalue subroutine"




#------ overriding constant function throws always a warning
sub with_proto () {4} 

# uncommenting garanties a warning
# sub with_proto () {5}

[download]

Cheers Rolf

In reply to Re^2: Inlining a "lexically-scoped scalar which has no other references" by LanX
in thread Inlining a "lexically-scoped scalar which has no other references" by LanX

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