Grep question

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

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Re: Grep question by Tanktalus (Canon) on Feb 03, 2005 at 17:28 UTC
`{ my $i; @statusoption = grep { $i or ($_ eq $status && ++$i) } @statusoption +; }` [download]	[reply] [d/l]
Re: Grep question by Roy Johnson (Monsignor) on Feb 03, 2005 at 17:42 UTC
Yes, though I'm not sure I'd recommend it over the other solutions posted: `@statusoption = splice(@statusoption, (grep $statusoption[$_] eq $status, 0..$#statusoption)[0]);` [download] Update: No need for splice when you just want a slice: `@statusoption = @statusoption[ (grep {$status eq $statusoption[$_]} 0..$#statusoption)[0] ..$#statusoption];` [download] Update: But splice is better than reassignment: `splice(@statusoption, 0, (grep $status eq $statusoption[$_], 0..$#stat +usoption)[0]);` [download] Here's one that will short-circuit `:-D`: `splice(@statusoption, 0, &{sub { grep {$status eq $statusoption[$_] and return $_} 0..$#statusop +tion }} );` [download] Caution: Contents may have been coded under pressure.	[reply] [d/l] [select]
Re^2: Grep question by hok_si_la (Curate) on Feb 03, 2005 at 18:12 UTC
Thanks all of you. I have made the suggested changes. I will need to look at them more in depth. I have a similar question for those of you with patience. I am trying to remove an item from an array using the delete function. Here is the code: `@statusoption = ('Waiting Approval' , 'Denied' , 'Approved' , 'Ordered +' , 'Building' , 'Built' , 'Shipped'); delete $statusoption[3];` [download] This simply yields ('Waiting Approval' , 'Denied' , 'Approved' , '' , 'Building' , 'Built' , 'Shipped') I would like to remove 'Ordered' from the array and shift all the other elements down an index truncating the array by 1. I appreciate you help, hok_si_la	[reply] [d/l]
Re^3: Grep question by Roy Johnson (Monsignor) on Feb 03, 2005 at 18:19 UTC
That's what splice is for: `splice(@statusoption, 3, 1);` [download] Caution: Contents may have been coded under pressure.	[reply] [d/l]
Re^4: Grep question by hok_si_la (Curate) on Feb 03, 2005 at 19:11 UTC
Re: Grep question by saintmike (Vicar) on Feb 03, 2005 at 17:32 UTC
First off, instead of `@statusoption[$i]` (which returns an array slice) please use `$statusoption[$i]` which returns an array element. Secondly, you could use grep to set a status flag once you've found what you're looking for: `my $found; @statusoption = grep { $found++ if $_ eq $status; $found } @statusoption;` [download]	[reply] [d/l] [select]
Re: Grep question by moot (Chaplain) on Feb 03, 2005 at 18:03 UTC
Not sure why you need to "pop the rest". If all you're trying to do is find the index of the status value itself, what's wrong with: `my %statusoption = ( "Waiting Approval" => 0, "Denied" => 1, "Approved" => 2, "Ordered" => 3, "Building" => 4, "Built" => 5, "Shipped" => 6, ); my $statusoption = $statusoption{$status};` [download] This assumes an item can't have more than one status, but since you're using a scalar to hold it that's not a bad assumption.	[reply] [d/l]
Re^2: Grep question by hok_si_la (Curate) on Feb 03, 2005 at 18:16 UTC
I will post the more code to give you guys a better idea of what I am trying to accomplish. I have no problem getting this to work, but I have been cleaning it up a bit. Originally it was about 40 lines, and now I have it down to this. In the process I am learning about perl Data structures. `###--- Define options for select Status ---### @statusoption = ('Waiting Approval' , 'Denied' , 'Approved' , 'Ordered +' , 'Building' , 'Built' , 'Shipped'); if ($purchase eq "Already Have") { delete @statusoption[3]; } if ($purchase eq "Virtual Machine") { delete @statusoption[3]; delete $statusoption[6]; } @statusoption = grep {$found++ if $_ eq $status; $found } @statusoptio +n; ###----------------------------------------###` [download]	[reply] [d/l]
Re^3: Grep question by hok_si_la (Curate) on Feb 03, 2005 at 18:23 UTC
Actually the code is as follows `###--- Define options for select Status ---### @statusoption = ('Waiting Approval' , 'Denied' , 'Approved' , 'Ordered +' , 'Building' , 'Built' , 'Shipped'); if ($purchase eq "Already Have") { delete $statusoption[3]; } if ($purchase eq "Virtual Machine") { delete $statusoption[3]; delete $statusoption[6]; } @statusoption = grep {$found++ if $_ eq $status; $found } @statusoptio +n; ###----------------------------------------###` [download]	[reply] [d/l]
Re: Grep question by sh1tn (Priest) on Feb 03, 2005 at 21:06 UTC
`my @statusoption = ('Waiting Approval' , 'Denied' , 'Approved' , 'Orde +rred' , 'Building' , 'Built' , 'Shipped'); my $status = 'Approved'; my ($position, $flag); my @popped = grep{ $flag and $_ or $_ eq $status and $flag++ or $position++, 0 }@statusoption; print "position:$position new: @popped$/" __END__ position:3 new: Orderred Building Built Shipped` [download]	[reply] [d/l]