C++ style boolean type in Perl?

mistaker has asked for the wisdom of the Perl Monks concerning the following question:

What do you reckon, what is the best way to implement C++ or Pascal style boolean data type in Perl?
I use enum module for this.
use enum qw(FALSE=0 TRUE=1);
Does it have some drawbacks I should be aware of? Don't know too much about enum module, opinions welcome.

Definition from Camel book says any string except for "" and "0", any number except for 0 and any reference are true, any undef value is false. So my enum seems to fulfill this definition, I am just curious whether the enum can misbehave in some situations...

-- Jan Stoklasa - "Mistaker" --
-- For those about to Perl, we salute you. --

Comment on C++ style boolean type in Perl? Download Code

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Re: C++ style boolean type in Perl? by japhy (Canon) on Sep 28, 2000 at 21:22 UTC
Um, there's no REAL need for explicit "true" and "false" datatypes in Perl. Watch: `if (foo()) { foo() returned a true value } if (!bar()) { bar() returned a false value } $DEBUG = 1; if ($DEBUG) { ... }` [download] If you really feel the need for 'true' and 'false', then please make this compromise with me: `use constant TRUE => 1; use constant FALSE => 0; # ... $DEBUG = TRUE; # ... if ($DEBUG) { ... }` [download] Please do NOT test for equality with TRUE or equality with FALSE. They are pointless test, and broken in cases of TRUE that aren't '1'. `$_="goto+F.print+chop;\n=yhpaj";F1:eval`	[reply] [d/l] [select]
RE: C++ style boolean type in Perl? by indigo (Scribe) on Sep 28, 2000 at 22:06 UTC
Mostly it is useless, and it is potentially dangerous if you are used to C++ booleans. C++ has only one false value, so: `if (x == FALSE)` [download] will work every time. However, in Perl you have: `if ($x == $false) if ($x eq $false)` [download] How do these work? What if $x = 0? or ''? or undef or 0.0? Are you sure? Perl has mutliple false values, so switching to a single false value is just asking for trouble. Perl is perl, don't try to redefine the language. It is like the Pascal programmer who starts all his C code with: `#define BEGIN { #define END }` [download] Server no purpose, confusing to others, and it just begging for weird ass bugs.	[reply] [d/l] [select]
Re^2: C++ style boolean type in Perl? by esharris (Monk) on Nov 20, 2005 at 11:32 UTC
IMHO, adding these 2 constants in Perl is not redefining the language. The resulting script still looks like Perl. I've use these 2 constants in my scripts and I think using them enhances readability.	[reply]
Re: C++ style boolean type in Perl? by AgentM (Curate) on Sep 28, 2000 at 21:50 UTC
I agree with japhy, but even constants bloat the code in the simple case of constants. That's some type of function call for every constant.	[reply]
RE: Re: C++ style boolean type in Perl? by japhy (Canon) on Sep 28, 2000 at 21:52 UTC
No, it isn't. When you `use constant`, Perl replaces the constants with the values they return at compile-time. `$_="goto+F.print+chop;\n=yhpaj";F1:eval`	[reply]