Loop Array - If $var is something write values until $var is something else

maikelnight has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Loop Array - If $var is something write values until $var is something else by GrandFather (Saint) on Sep 29, 2018 at 23:32 UTC
I'm not sure what your "could be removed" string in the output is supposed to denote, but assuming that output string could be removed, the following may provide some ideas: use strict; use warnings; my @cleared = ( 'JOB::HEREISASTRING', 'Something', 'StringA', 'StringB', 'StringC', 'StringD', 'Something Else', 'StringE', 'StringF', 'StringG', 'StringH ', 'JOB::HEREISANOTHERSTRING', 'Something', 'StringI', 'StringJ', 'StringK', 'StringL', 'Something Else', 'StringM', 'StringN', 'StringO', 'StringP ', ); my @result; my $prefix = '~~Something~~'; foreach my $x (@cleared) { if ($x =~ /JOB::(.*)/) { $prefix = ""; } elsif ($x =~ m/^Something Else/) { $prefix = "~~Something Else~~"; } elsif ($x =~ m/^Something/) { $prefix = "~~Something~~"; } print "$prefix$x\n"; } [download] Prints: JOB::HEREISASTRING ~~Something~~Something ~~Something~~StringA ~~Something~~StringB ~~Something~~StringC ~~Something~~StringD ~~Something Else~~Something Else ~~Something Else~~StringE ~~Something Else~~StringF ~~Something Else~~StringG ~~Something Else~~StringH JOB::HEREISANOTHERSTRING ~~Something~~Something ~~Something~~StringI ~~Something~~StringJ ~~Something~~StringK ~~Something~~StringL ~~Something Else~~Something Else ~~Something Else~~StringM ~~Something Else~~StringN ~~Something Else~~StringO ~~Something Else~~StringP [download] The trick is to use a "state" variable (in this case $prefix) to remember what state the parser is in. This is a trivial case of a state machine which can be used to simplify implementing many parsing and processing systems. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply] [d/l] [select]
Re^2: Loop Array - If $var is something write values until $var is something else by maikelnight (Sexton) on Oct 01, 2018 at 10:54 UTC
Dear All, thanks much for you input! Dear GrandFather, the state variable is what i was after and i thought in that direction as i said. thank you. it solved my issue. Big ups!	[reply]
Re: Loop Array - If $var is something write values until $var is something else by Marshall (Canon) on Sep 29, 2018 at 17:32 UTC
Hi maikelnight!, First when you post a question here, the ideal situation is that you provide a completely runnable example including a sample of the data. That way I can just download the code into my Perl environment, push the "go button" and replicate exactly what you are seeing. update: Basically the easier you make it for the Monks to run your code, the more likely you are to get a prompt and good response. Right now I'd have to work my brain a bit to reverse engineer some data that would produce your results. Things are much better if I don't have to do that. Do you have `use strict; use warnings;`? That is important. It looks like `@cleared` is an AoA (Array of Array), i.e. a 2-D structure. This code: `($x =~ m/^Something Else/)` won't work because $x is a reference to an array. You need `$x->[someIndex]`to get a string to compare against. I am surprised if what you have doesn't throw some kind of an error? Why don't you rename $x, $row_ref or something like that? $x is not very descriptive. This does look weird: `unless ($x =~ m/^Something Else/){ print "~~Something Else~~", $x, "\n"; }` [download] That is the same as: print ~~Something Else~~ if $x is not Something Else , which is kinda weird. `if ($x->[someIndex] !~ m/^Something Else/){}` [download] Does that help? Enclose the output in code tags so that we can see the line breaks.	[reply] [d/l] [select]
Re^2: Loop Array - If $var is something write values until $var is something else by johngg (Canon) on Sep 29, 2018 at 18:05 UTC
It looks like `@cleared` is an AoA The curly braces suggest to me that it might be an AoH instead. `johngg@shiraz:~/perl/Monks$ perl -Mstrict -Mwarnings -E ' my @AoH = ( { jobName => q{Director}, jobProfile => q{Three day week}, }, { jobName => q{Manager}, jobProfile => q{9to5}, }, ); foreach my $job ( @AoH ) { say $job; say $job->{ jobProfile }; }' HASH(0x562033e731e0) Three day week HASH(0x562033e92488) 9to5` [download] I agree though that the `unless ($x =~ m/^Something Else/){` does look weird as it would seem to be trying to match against a stringified reference. I suspect that we are not seeing the whole story. Cheers, JohnGG	[reply] [d/l] [select]
Re^3: Loop Array - If $var is something write values until $var is something else by Marshall (Canon) on Sep 29, 2018 at 18:38 UTC
I agree. I misread the fonts between `{ and [` without my reading glasses! My dev environment has larger fonts than my browser! In any event, these 2 code statements from the OP are inconsistent with the type of value of $x: `my $jobprofil = $x->{JobProfil}; ...later this... unless ($x =~ m/^Something Else/){` [download] Something is wrong here. I am hoping that a full runnable code example with `use strict; use warnings;` will be very helpful.	[reply] [d/l] [select]
Re^4: Loop Array - If $var is something write values until $var is something else by Anonymous Monk on Sep 29, 2018 at 20:02 UTC
Re^5: Loop Array - If $var is something write values until $var is something else by AnomalousMonk (Archbishop) on Sep 29, 2018 at 22:36 UTC
Re^5: Loop Array - If $var is something write values until $var is something else by Marshall (Canon) on Sep 29, 2018 at 20:53 UTC
Re^5: Loop Array - If $var is something write values until $var is something else by johngg (Canon) on Sep 29, 2018 at 23:02 UTC
Some notes below your chosen depth have not been shown here
Re^5: Loop Array - If $var is something write values until $var is something else by Marshall (Canon) on Sep 30, 2018 at 03:00 UTC
Re^5: Loop Array - If $var is something write values until $var is something else by Marshall (Canon) on Oct 03, 2018 at 22:08 UTC
Re: Loop Array - If $var is something write values until $var is something else by AnomalousMonk (Archbishop) on Sep 29, 2018 at 19:32 UTC
maikelnight: Further to Marshall's post: Please see Short, Self-Contained, Correct Example. The monks grow sullen and silent when you make them do a lot of work in order to give free advice. Others have noted that you don't seem to have warnings and strictures enabled. Let me repeat: Especially if you're a beginning Perler, always have the two statements `use warnings;` `use strict;` at the beginning of your script. See (and use!) warnings and strict. Finally, you seem confused about just what is in the `@cleared` array; we certainly are. Using some kind of data dumper can bring much enlightenment. Popular are Data::Dumper`::Dump()` (which is core and so should already be loaded in your system), and Data::Dump`::dd()` (which I like better, but it's not core, so you may have to load it yourself). Use one or the other `use Data::Dumper;` `...` `print Dumper \@cleared;` or `use Data::Dump;` `...` `dd \@cleared;` and you may find yourself much further down the road to a working application! Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^2: Loop Array - If $var is something write values until $var is something else by maikelnight (Sexton) on Sep 29, 2018 at 20:05 UTC
Sorry for confusing, should have removed the reference part as its not really important to my question. I removed it, use strict and warnings and now here is it: `my @result; foreach my $x (@cleared) { if ($x =~ /JOB::(.*)/){ print $x, "\n"; } else { unless ($x =~ m/^Something/){ print "~~Something~~", $x, "\n"; } else { unless ($x =~ m/^Something Else/){ print "~~Something Else~~", $x, "\n"; } } } }` [download] Lets see the @cleared (Dump): `$VAR1 = 'JOB::HEREISASTRING'; $VAR2 = 'Something'; $VAR3 = 'StringA'; $VAR4 = 'StringB'; $VAR5 = 'StringC'; $VAR6 = 'StringD'; $VAR7 = 'Something Else'; $VAR8 = 'StringE'; $VAR9 = 'StringF'; $VAR10 = 'StringG'; $VAR11 = 'StringH '; $VAR12 = 'JOB::HEREISANOTHERSTRING'; $VAR13 = 'Something'; $VAR14 = 'StringI'; $VAR15 = 'StringJ'; $VAR16 = 'StringK'; $VAR17 = 'StringL'; $VAR18 = 'Something Else'; $VAR19 = 'StringM'; $VAR20 = 'StringN'; $VAR21 = 'StringO'; $VAR22 = 'StringP ';` [download] Output: `JOB::HEREISASTRING ~~Something Else~~Something ~~Something~~StringA ~~Something~~StringB ~~Something~~StringC ~~Something~~StringD ~~Something~~Something Else ~~Something~~StringE ~~Something~~StringF ~~Something~~StringG ~~Something~~StringH JOB::HEREISANOTHERSTRING ~~Something Else~~Something ~~Something~~StringI ~~Something~~StringJ ~~Something~~StringK ~~Something~~StringL ~~Something~~Something Else ~~Something~~StringM ~~Something~~StringN ~~Something~~StringO ~~Something~~StringP` [download] I wish output: JOB::HEREISASTRING ~~Something Else~~Something Else (could be removed) ~~Something~~StringA ~~Something~~StringB ~~Something~~StringC ~~Something~~StringD ~~Something Else~~Something Else (could be removed) ~~Something Else~~StringE ~~Something Else~~StringF ~~Something Else~~StringG ~~Something Else~~StringH JOB::HEREISANOTHERSTRING ~~Something Else~~Something Else (could be removed) ~~Something~~StringI ~~Something~~StringJ ~~Something~~StringK ~~Something~~StringL ~~Something Else~~Something Else (could be removed) ~~Something Else~~StringM ~~Something Else~~StringN ~~Something Else~~StringO ~~Something Else~~StringP [download] In fact i want to tag my values from a start until a match occurs and tag it different and so on.... What comes to my mind is that with foreach loop variable $x changes and in the loop is again "Something"!?	[reply] [d/l] [select]
Re^3: Loop Array - If $var is something write values until $var is something else by BillKSmith (Monsignor) on Sep 30, 2018 at 00:58 UTC
You seem to want the flip-flop operator. Ref: Range Operators in perlop. A "state variable" is not needed because the state is stored in the operator. ?type 1223291.pl use strict; use warnings; my @cleared = ( 'JOB::HEREISASTRING', 'Something', 'StringA', 'StringB', 'StringC', 'StringD', 'Something Else', 'StringE', 'StringF', 'StringG', 'StringH ', 'JOB::HEREISANOTHERSTRING', 'Something', 'StringI', 'StringJ', 'StringK', 'StringL', 'Something Else', 'StringM', 'StringN', 'StringO', 'StringP ', ); foreach (@cleared) { if (/JOB::(.*)/){ print $_, "\n"; next; } print '~~Something'; if ( !(/Something$/ ... /Something Else$/) or /Else/) { print ' Else'; } print "~~$_\n"; } ?perl 1223291.pl JOB::HEREISASTRING ~~Something~~Something ~~Something~~StringA ~~Something~~StringB ~~Something~~StringC ~~Something~~StringD ~~Something Else~~Something Else ~~Something Else~~StringE ~~Something Else~~StringF ~~Something Else~~StringG ~~Something Else~~StringH JOB::HEREISANOTHERSTRING ~~Something~~Something ~~Something~~StringI ~~Something~~StringJ ~~Something~~StringK ~~Something~~StringL ~~Something Else~~Something Else ~~Something Else~~StringM ~~Something Else~~StringN ~~Something Else~~StringO ~~Something Else~~StringP ? [download] UPDATE: Added reference Bill	[reply] [d/l]
Re: Loop Array - If $var is something write values until $var is something else by davido (Cardinal) on Sep 29, 2018 at 19:21 UTC
So is it accurate that your datastructure looks something like this? `my @cleared = ( 'Something', {JobProfil => undef}, {JobProfil => 1}, 'Something else that should match', 'This one should not match', );` [download] Why are there hashrefs in some elements and not in others? Possibly the first test you should be doing is checking if `$x` contains a reference, at each iteration. Otherwise, you'll be trying to dereference `$x` as a hashref when it's actually just a plain old string. This would run afoul of `strict 'refs';`. Dave	[reply] [d/l] [select]


Pathologically Eclectic Rubbish Lister
	PerlMonks