"while" is the wrong looping construct for going over file lines, and that's across a great many computer languages. It will stop when it encounters a false line- typically an empty line or '0'
Try "for" -y On Sat, Jan 18, 2020 at 4:45 PM William Michels <w...@caa.columbia.edu> wrote: > Hello All, > > I've been reviewing literature that discusses using raku/perl6 as a > replacement for common unix utilities. One important unix utility is > "cat". I looked at docs/blogs and found a recommendation to use "$*IN" > along with "slurp" (references at bottom). Using a seven-line test > file "testthis_abc_def.txt" below (1), the recommended "slurp" code > works as expected (2). > > However, another recommendation to use "$*IN" along with the "get" > method fails when a blank line is encountered, only returning > truncated output (3). I tried correcting truncated output seen with > "get" by playing with the command-line arguments "-ne" (4) and "-pe" > (5), but only ended up mangling output even further. > > Can "get" be used in when writing raku/perl6 replacement code for "cat"? > > Any advice appreciated, > > Bill. > > > [1]mydir$ cat testthis_abc_def.txt > a > b > c > > d > e > f > [2]mydir$ perl6 -e 'say $*IN.slurp;' < testthis_abc_def.txt > a > b > c > > d > e > f > > [3]mydir$ perl6 -e '.say while $_ = $*IN.get;' < testthis_abc_def.txt > a > b > c > [4]mydir$ perl6 -ne '.say while $_ = $*IN.get;' < testthis_abc_def.txt > b > c > e > f > [5]mydir$ perl6 -pe '.say while $_ = $*IN.get;' < testthis_abc_def.txt > b > c > > e > f > (Mu) > [6]mydir$ > > > REFERENCES: > 1. https://docs.raku.org/routine/slurp > 2. https://docs.raku.org/routine/get > 3. https://andrewshitov.com/2019/09/09/the-cat-utility-written-in-perl-6/ > 4. > https://stackoverflow.com/questions/52597984/catching-exception-of-a-shell-command-in-perl-6 >
