Re: sorting an array with mixed elements...

I presume you meant

print sort { (split ":", $a)[0] <=> (split ":", $b)[0] } @table;
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sort {...} @table will sort the contents of the array @table according to the contents of {...}

sort works by comparing pairs of elements, calling them $a and $b within the {...}.

split ":", $a will split $a into a list using ":" as the separator

(...)[0] will return the first element of that list

So, given input like:

111:A:B;C
2:D:E:F
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This will sort by looking at the first field only, namely "111" & "2", treating them as numbers because of the use of <=>.

update: Oops, I forgot to mention <=>, the numeric comparison operator, usually called the spaceship operator.

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Re^2: sorting an array with mixed elements... by cgmd (Beadle) on Jun 09, 2007 at 23:08 UTC
I believe I'm confused by the occurrence and use of split(), sort() and print(), all, on one line. Is there a way to run these three functions separately, but sequentially? Thanks!	[reply]
Re^3: sorting an array with mixed elements... by lidden (Curate) on Jun 09, 2007 at 23:51 UTC
`print sort { (split ":", $a)[0] <=> (split ":", $b)[0] } @table;` Is the same as: `my @sorted = sort { my @A = split ':', $a; my @B = split ':', $b; $A[0] <=> $B[0]; } @table; print @sorted;` [download]	[reply] [d/l] [select]
Re^3: sorting an array with mixed elements... by FunkyMonk (Bishop) on Jun 10, 2007 at 08:18 UTC
You can't split it up completely, but you could write like so `sub compare { (split ":", $a)[0] <=> (split ":", $b)[0] } my @sorted = sort compare @table; print @sorted;` [download] It would also benefit from applying a Schwartzian Transform (ST): `print map { $_->[1] } sort { $a->[0] <=> $b->[0] } map { [ (split /:/, $_)[0], $_ ] } @table;` [download] A ST is read from the bottom up `map { [ (split /:/, $_)[0], $_ ] } @table;` [download] creates an anonymous array with the thing you want to sort on as the first element (`(split /:/, $_)[0]`), and the original line as the second(`$_`) `sort { $a->[0] <=> $b->[0] }` [download] does the sort, using the first element of the arrays you just created `map { $_->[1] }` [download] returns the original line from the second element of your arrays. There's loads of material on the interweb on the ST if you want to know more. update: fixed a couple of typos	[reply] [d/l] [select]
Re^4: sorting an array with mixed elements... by blazar (Canon) on Jun 10, 2007 at 21:38 UTC
You can't split it up completely, Just a tiny bit more, mixing your "solution" with lidden's: `sub compare { my @A = split /:/, $a; my @B = split /:/, $b; $A[0] <=> $B[0]; } my @sorted = sort compare @table; print @sorted;` [download] (Incidentally I also changed the first argument to split, since it must be a pattern - strings are automatically converted of course, but there's one special case, so...) If it ain't clear like this... I don't know what could ever be!!	[reply] [d/l]