scalar function

[fatted]

Consider 2 statements:

my $value = 3 + @array;
my $value = 3 + scalar(@array);

They both result in $value having the same value (as far as I've seen).

Is there any difference, or to put it another way, what's the point in using scalar?

 

[Gunnar Hjalmarsson]

Consider 2 statements:

my $value = 3 + @array;
my $value = 3 + scalar(@array);

They both result in $value having the same value (as far as I've
seen).

Is there any difference, or to put it another way, what's the point
in using scalar?

The point with using scalar is to _ensure_ a return value in scalar
context. In this case, you get it implicitly - out from context -
by including @array in an addition.

 

[David Bouman]

Consider 2 statements:

my $value = 3 + @array;
my $value = 3 + scalar(@array);

They both result in $value having the same value (as far as I've seen).

Your insights are correct;

Is there any difference, or to put it another way, what's the point in using scalar?

Consider:

print 3, @array;
print 3, scalar(@array);

 

[Shawn Corey]

Hi,

The point of the scalar function is to tell Perl you want the number of
elements of the array rather than the array itself in those contexts
where it's unclear whether the context is scalar or array.

Example: parameters of a function.

&foo( @arr ); # send the array
&foo( scalar( @arr )); # send the number of elements

If you're not sure, use it anyway. I always use it just to make
understanding the program clearer.

 

[David Bouman]

The point of the scalar function is to tell Perl you want the number
of elements of the array rather than the array itself in those
contexts where it's unclear whether the context is scalar or array.

The point of scalar EXPR is to force a scalar context upon it's
expression argument. It just so happens that an array in scalar
context evaluates to its number of elements but that's not the
intended purpose of the scalar operator.