Re: way of declare an integer variable instead use /^\d+$/

Replies are listed 'Best First'.
Re^2: way of declare an integer variable instead use /^\d+$/ by vincentaxhe (Beadle) on May 25, 2024 at 09:28 UTC
someone might disagree, it's no good for perl.	[reply]
Re^3: way of declare an integer variable instead use /^\d+$/ by LanX (Saint) on May 26, 2024 at 11:14 UTC
Perl is, contrary to C, a dynamically typed language. A static typing, i.e. at compilation time, is nearly impossible. Otherwise you'd need to type everything, including the result of functions. Even then....š A check at runtime is costly, that's why dynamically typed languages are slower, but easier to code. As I already said, you could `tie` the variable with a self-made `STORE (This, Value)` function which does your checks on Value before storing it. Attribute::Handlers has an example for Syntactic sugar to "hide" the tie-ing procedure behind an attribute. I'm not aware of any CPAN modules already providing that, especially because there are certainly different models how to react on wrong types ( `die` , `warn` , transform, combine) I already gave you all the links, you'd need to do it yourself for your own needs. For instance `1E0` is a whole number in float notation, opinions will differ. I'm saying all of this for completeness, because it's a total overkill for your problem. There is no magic wand which can do the heavy lifting for you... Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery} š) Perl, like other dynamic languages, does a lot of DWIM typecasting of variables. This doesn't translate well if you want to keep it fast.	[reply] [d/l] [select]
Re^4: way of declare an integer variable instead use /^\d+$/ by bliako (Abbot) on May 26, 2024 at 11:41 UTC
`As I already said, you could tie the variable with a self-made STORE ( +This, Value) function which does your checks on Value before storing +it.` [download] allow me to clarify the above, in reference to what you said before that: `You could use Tie::Scalar to make sure that a var $x will always stay +an integer, by declaring STORE. But that will slow down every operati +on on $x.` [download] , just use the slow Tie::Scalar to only do the validation, then store the validated integer into a "normal" variable.	[reply] [d/l] [select]
Re^5: way of declare an integer variable instead use /^\d+$/ by LanX (Saint) on May 26, 2024 at 11:59 UTC
Re^4: way of declare an integer variable instead use /^\d+$/ by vincentaxhe (Beadle) on May 27, 2024 at 01:50 UTC
Tie::Scalar whatever it can do,it's overkill to declare an integer, I do not know how to implement it, I seldom use class in my scripts. It may be either-or, I can not have both, regex is a much general define method, I'm learning to appreciate it, since 'every perl script use regex'	[reply]


Welcome to the Monastery
	PerlMonks