Re: Deleting Elements from an Array without their Index Number?

Do you want to remove coin from the array?

my @not_coin = grep { $_ ne 'coin' } @array;
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Or do you want to replace coin by undef?

my @not_coin = map { $_ eq 'coin' ? undef : $_ } @array;
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Re^2: Deleting Elements from an Array without their Index Number? by Fletch (Bishop) on Jul 23, 2006 at 23:58 UTC
And of course you could also use grep to determine the index if you later would like to use it to remove elements with splice. `my @coin_idx = grep { $array[ $_ ] eq 'coin' } 0..$#array;` [download]	[reply] [d/l]
Re^2: Deleting Elements from an Array without their Index Number? by diotalevi (Canon) on Jul 24, 2006 at 00:32 UTC
I like how writing these as map+ternary makes it obvious that grep is just a specialization of map. `my @not_coin = map { $_ eq 'coin' ? () : $_} @array; # Or do you want to replace coin by undef? my @not_coin = map { $_ eq 'coin' ? undef : $_} @array;` [download] ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l]
Re^3: Deleting Elements from an Array without their Index Number? by Anonymous Monk on Jul 24, 2006 at 15:18 UTC
And map is a specialization of foreach+push. `my @not_coin; foreach (@array) { push(@array, $_ eq 'coin' ? () : $_); }` [download] How does this help?	[reply] [d/l]
Re^4: Deleting Elements from an Array without their Index Number? by diotalevi (Canon) on Jul 24, 2006 at 15:45 UTC
How does this help? It's always good to know the more general form of your specializations. Knowing that grep is map+flat list, you can turn chained grep/map into single expressions to avoid traversing your entire list multiple times, once for each step in the chain. ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply]