Optional parameters: Difference between revisions
Added Perl.
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Underscore (talk | contribs) (Added Perl.) |
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OCaml does not support optional positional parameters, because, since OCaml supports currying, it would conflict with partial applications, where you do not provide all the arguments to a function, and it results in a function which expects the remaining arguments.
=={{header|Perl}}==
This function expects its first argument to be a reference to an array of arrays. It interprets any remaining arguments as a hash of optional parameters.
<lang perl>sub sorttable
{my @table = @{shift()};
my %opt =
(ordering => sub {$_[0] cmp $_[1]}, column => 0, reverse => 0, @_);
my $col = $opt{column};
my @result = sort
{$opt{ordering}->($a->[$col], $b->[$col])}
@table;
return ($opt{reverse} ? [reverse @result] : \@result);}</lang>
An example of use:
<lang perl>my $a = [["a", "b", "c"], ["", "q", "z"], ["zap", "zip", "Zot"]];
foreach (@{sorttable $a, column => 1, reverse => 1})
{foreach (@$_)
{printf "%-5s", $_;}
print "\n";}</lang>
=={{header|Python}}==
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