"Perl: Can someone please explain this code "sort { $a <=> $b } @unsorted""

Post #303032271 by drl on Thursday 14th of March 2019 12:09:19 PM

Hi, Tanu.

If you were to execute perldoc -f sort, you would find explanation:
Code:
    sort SUBNAME LIST
    sort BLOCK LIST
    sort LIST
            In list context, this sorts the LIST and returns the sorted list
            value. In scalar context, the behaviour of "sort()" is undefined.

            If SUBNAME or BLOCK is omitted, "sort"s in standard string
            comparison order. If SUBNAME is specified, it gives the name of a
            subroutine that returns an integer less than, equal to, or greater
            than 0, depending on how the elements of the list are to be
            ordered. (The "<=>" and "cmp" operators are extremely useful in
            such routines.)
...

and if executed perldoc perldoc, one sees:
Code:
NAME
    perldoc - Look up Perl documentation in Pod format.

SYNOPSIS
        perldoc [-h] [-D] [-t] [-u] [-m] [-l] [-F]
...

so you can find answers to questions like this by yourself. Of course, not all documentation is easily understandable, so we can help in situations like that.

These commands were run on a system like:
Code:
OS, ker|rel, machine: Linux, 3.16.0-7-amd64, x86_64
Distribution        : Debian 8.11 (jessie) 
perl 5.20.2
Perldoc v3.23, under perl v5.020002 for linux

Best wishes ... cheers, drl
This User Gave Thanks to drl For This Post:
 

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