Re: commify_series script in cookbook page 94

Rob Dixon wrote:
Richard Lee wrote:
While reading perl cookbook, I came to page 94 and having a hard time understanding this particular phrase

my $sepchar = grep( /,/ => @_ ) ? ";" : ",";

I recognize the ternary operator and grep but I am not sure how they are forming the meaning together.

I thought grep needed lists to work on ? and grep(/,/ => @_), I am not sure where it's getting the list from

my @results = grep EXPR, @input_list;
my $count = grep EXPR, @input_list;

And I also don't understand what ";" is doing in the ternary operator??

I think I understand the rest of the program though..

Can someone help me out please?

The => operator is misleading - it's exactly equivalent to a comma in
this case, so

grep(/,/, @_)

(in scalar context) returns the number of elements of @_ that contain a
comma character. Either comma or semicolon is assigned to $sepchar
according to whether that count is false (zero) or true (non-zero).

So, in plain English, if any of the elements of @_ contain a comma then
$sepchar is set to a semicolon; otherwise it is set to a comma.

HTH,

Rob
thanks guys!!

Understood them.. moving on.....


.

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    (perl.beginners)