Re: not_null function

Hi Bart, On Thu, Jul 3, 2014 at 5:40 PM, Xen <xen@dds.nl> wrote: > Heya, > > I was just wondering about something. > > It seems way more natural and flowing to have and use a "not_null" > function in addition to some "is_null" that currently exists. > > The reason is that most of the time you are not checking null condition, > you are really checking the non-null condition. > > But a line like "if (!is_null($a))" feels like there are two verbs in it. > For this particular case I would use this: if (isset($a)) For undefined variables it will return false and for defined variables it's equivalent to the expression $a !== null. > It is like you are saying "if $a is not is null". > > It is different for the "empty" function because there is no "is_" prefix > in it. So "if (!empty($a)) feels completely sane. > > So generally I will *want* to test a null condition but I just hope my > variable won't contain anything that evaluates to false and just test "if > ($a)". > > If there was a not_null() I would use that instead, because "if > (not_null($a))" only contains one "verb" instead of two. > > And I would define that helper function myself, but I don't want to write > code that another person would not be able to run just because not_null is > not defined in his library. > > -------- > In general I believe this is rather a problematic feature of most > languages. > > The "if" statement implies a verb, but many functions and methods also > contain a verb in their name. > > This seems to be only the case for the "is" verb. I know in my language > (Dutch) the "to be" verb (zijn) is treated differently from all other verbs > when it comes to the adverb/adjective difference. > > When you state "I am good" the adjective is used, but "I work good" should > be "I work well". The adjective applies to the subject "I" but the adverb > applies to the verb "work". I guess there are all sorts of mixtures, "I am > well" is also used. But I think it is improper. > > Thus, "if (has_members())" feels natural because it uses a different verb > replacing the default "is". > > But "if (is_null())" feels odd because "if (null())" would say the same > thing only more concise and more natural as far as if statements go, or at > least it seems that way to me. > > Personally I try to avoid those "is_something" functions whenever I can. > It is not so much an issue if it is some rarely used library call. > > Like WordPress has functions like "is_single()" which returns a boolean > indicating whether the currently loaded page is a single post display. > > But notice that "if (single())" would give very little information as to > what you were actually testing. There is no parameter, and just "single" > would be so general that it would completely obfuscate the fact that it had > to do with WordPress. It would have to become "page_is_single()" although > "page" is (improperly) dedicated to a special type of post that sits > outside of the regular post structure. They ought to rename it to > "staticpage" or "static". "page_is_single" and > "page_is_home" and > "page_is_category" would be more descriptive. > > But in any case, this language incongruency is most annoying with core > functions you have to use all the time, or would be using all the time if > they were okay. > > So my suggestion would be to consider introducing at least "not_null". > "isset" seems to be a different category, if only because the verb is not > visually separated from the condition. > > So "if (isnull($a))" would again be more natural. But because the verb is > visually separated using the underscore, you get two verbs in your mind. > Perhaps creating an "isnull" alias and then deprecating the "is_null" > function would be best. > There's also is_array(), is_bool(), etc. so changing only is_null() would be a big wtf ;-) You could propose to change isset() into is_set() though =D > Regards, > > Bart Schouten > > ps. please "reply all" for I am not subscribed as of yet. > > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: http://www.php.net/unsub.php > > -- -- Tjerk