0: #Want to sort a complex data structure by some element
1: #efficiently? For example, how do you sort an array
2: #of strings by their length? Use the transform:
3: @sorted = map { $_->[1] }
4: sort { $a->[0] <=> $b->[0] }
5: map { [ length $_, $_ ] } @strings;
6:
7: #Confused? Put in temporary arrays,
8: #just to see what we're doing.
9:
10: # create a temporary array of anonymous arrays
11: # (0: length of the string, 1: the string)
12: @temp = map { [ length $_, $_ ] } @strings;
13: # sort by length
14: @temp = sort { $a->[0] <=> $b->[0] };
15: # grab just the strings and put them in @ordered
16: @sorted = map { $_->[1] } @temp;
17:
18: #Knowing the context of certain operations
19: # and being able to chain them together
20: # is crucial to a deep and idiomatic
21: # understanding of Perl.
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