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Postings from March 2002
On 2002.03.06 23:10 Yitzchak Scott-Thoennes wrote: > I become more and more convinced this is broken as is. > > For instance: > ~/bleadperl/perl $perl -wle'open FOO, "<a" and readline FOO' > Name "main::FOO" used only once: possible typo at -e line 1. "readline FOO" is currently equivalent to "readline 'FOO'", so FOO is used only once, in open(). (BTW perlfunc says that the correct syntax is "readline *FOO", and does not mention readline without an argument.) The problem as I see it : The optimizations on the op tree for the <> operator are done in toke.c. (e.g. providing the implicit ARGV argument, etc. Look at function toke.c:S_scan_inputsymbol). These do not occur with the readline() syntax. But both happen to produce the same op, codenamed readline. Thus the optree for readline(FH) is broken. Examples : $ bleadperl -MO=Concise -ereadline 4 <@> leave[t1] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v ->3 3 <0> readline[t1] v ->4 <-------no child ! $ bleadperl -MO=Concise -e'<>' 5 <@> leave[t1] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v ->3 4 <1> readline[t1] vK/1 ->5 3 <$> gv(*ARGV) s ->4 $ bleadperl -MO=Concise -e 'readline FOO' 5 <@> leave[t1] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v ->3 4 <1> readline[t1] vK/1 ->5 3 <$> const(PV "FOO") s/BARE ->4 <-----bareword string value! $ bleadperl -MO=Concise -e '<FOO>' 5 <@> leave[t1] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v ->3 4 <1> readline[t1] vK/1 ->5 3 <$> gv(*FOO) s ->4 So your patch looks like it corrects some of the problems (I haven't tried it yet), but it won't add a missing ARGV to readline(). Minor problem, if you forbid the no-arg syntax.Thread Previous | Thread Next