2022-7-9 6:31 Paul "LeoNerd" Evans <leonerd@leonerd.org.uk> wrote: > On Sat, 9 Jul 2022 06:14:36 +0900 > Yuki Kimoto <kimoto.yuki@gmail.com> wrote: > > > I'm interested in this topic. > > > > I have questions. > > > > 1. Can this be resolved in tokenizer? > > > > This means ${^INPUT_LINE_NUMBER} is replaced with $. in toke.c. > > No. That's really the variable's name, as can be demonstrated via > softrefs: > > $ perl -E '"hello" =~ m/\w+/p; say ${^MATCH}; my $varname = "\cMATCH"; > say $$varname' > hello > hello > > Oh, it is not so easy. Leon seems to have some problems in the stab implementation. Softref maybe means symbolic reference. I changed the question. Is the alias of the predefined variable the same as the alias such as "$var" in "for my $var (...)"? > > 3. Can only the aliases that are often used be added? > > > > For example, in my experience. I use $., $/, $$, $@, $!, $<, $> etc. > > > > If 1 and 3 are ok, I can write RFC. > > I'm not sure what significance part 1 has on writing the RFC. That > feels like a purely implementation-level question. > > I'm thinking of the problem of *quantity* when I implement them because predefined variables are too many. 1. RFC-X1 Some part of them 2. RFC-X2 All. > > > 2. Is the brace required? > > > > > > Is $^INPUT_LINE_NUMBER allowed? > > > > Yes. $^ is already a variable on its own (a little-known part related > > to formats). > > > I should clarify: > > Yes, the brace is required. > No, $^INPUT_LINE_NUMBER is not allowed. OK. I understand "$^INPUT_LINE_NUMBER is not allowed".Thread Previous | Thread Next