Implicit type conversion: Difference between revisions

=={{header|Perl}}==

Perl is the original DWIM language, implicit type conversion is the default mode of operation. Perl does not have static types; the concept of distinct integers/strings/floats is not present. Instead, operators defines how the operands will behave. An operator that requires a string coerces its operand into a string, an operator that requires an integer coerces its operand into an integer, and so forth.

<lang perl>print 1 + '2'; # 3

print '1' + '2'; # 3

print 1 . 1; # 11

$a = 1;

$b = 2;

say "$a+$b"; # 1+2

# Even if you intentionally jumble the expected roles of numbers and strings, thing just work out

say hex int( (2 . 0 x '2') ** substr 98.5, '2', '2' ) . 'beef'; # 1359599</lang>

On the other hand, since Perl gives you a lot of rope, you have to be careful what you do with it. The expression

<code>'x' + 1</code> will return the answer '1', silently glossing over the meaningless use of an alphabetic character in addition.

This is the reason that <code>use warnings</code> should be present in most all your Perl code. Enabling warnings will alert you that <tt>Argument "x" isn't numeric in addition</tt>.