Php null case sensitive

Improve this answer. Abdulla Nilam Abdulla Nilam Sorry, but I just have to comment that this in no way answers the question. I asked why? I wonder why there is always somebody who promptly copy pastes part of some manual without actually reading the whole OP My answer would be that this is just because PHP was made by more developers and they simply did not communicate properly, thus causing this confusing mess. My question is how can I disable this weird behavior? I find case sensitivity in variable names just as a huge opportunity for various hard to find bugs and errors.

There is no other value in this approach sorry Keep in mind that TRUE and FALSE are also case- insensitive as they're also language constructs, and not constants in a technical sense, since multiple values can be equal to them. Can I ask why you had this question protected? AbdullaNilam Already read that. In particular, the part with Questions are usually protected because they have attracted either spam answers or "noisy" answers such as "thank you", "this worked for me", or "I'm also having this problem" from new users who may mistake the site as a traditional forum.

The only problem here is not that type of response, but answers which ignore the question entirely. Show 1 more comment. Why is PHP partially case senstive? You know, I never noticed the extra optional parameter on the define function. It appears to be a legacy of a mixed heritage.

Case sensitive variables, constants, array keys, class properties, class constants Case insensitive functions, class constructors, class methods, keywords and constructs if, else, null, foreach, echo etc.

Abhishek Sharma Abhishek Sharma 6, 1 1 gold badge 13 13 silver badges 20 20 bronze badges. Yes, but why? The Overflow Blog. Podcast Making Agile work for data science. Stack Gives Back NULL is supposed to indicate the absence of a value, rather than being thought of as a value itself.

It's the empty slot, it's the missing information, it's the unanswered question. It's not a jumped-up zero or empty set. This is why a variable containing a NULL is considered to be unset: it doesn't have a value. Setting a variable to NULL is telling it to forget its value without providing a replacement value to remember instead.

The variable remains so that you can give it a proper value to remember later; this is especially important when the variable is an array element or object property.

The PSR-2 standard requires true , false and null to be in lower case. From the list of backward incompatible changes in PHP 5. According to PSR-2 standard :. So basically, if you want to play nice with open source style particulars, Booleans gotta be lower case. It doesn't matter, true is exactly the same as TRUE. Same goes for false and null.

I haven't heard that it would have mattered at any point. Only thing restricting or encouraging you to use upper or lowercase might be your company's or your own coding guidelines.

Other than that, you're free to use either one and it will not lead in any issues. So we can see that performance is very slightly touched by the booleans case - lowercase is faster.

But certainly you won't see. Personally I've always used the lowercase form, but for no particular reason other than to make my code look tidy, the only place I use capital letters is when camel casing class names and variable names. One advantage to using uppercase that comes to mind though is that they stick out and are easy to find in code. I came across this old question while asking myself the same thing. Writing those lines in a php5 code is like writing a comment.

I am years late to the party but wanted to mention something interesting that isn't in the thread yet. All spellings are equivalent. Which led me to a bewildered state of mind and a search which found this page. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Uppercase Booleans vs. Asked 12 years ago. Active 1 year, 3 months ago. Viewed 34k times. Improve this question.

FrustratedWithFormsDesigner Austin Hyde Austin Hyde There is a number of sites saying that writing it lowercase is supposedly "much faster", but without citing any serious sources. Interested to see whether anything comes up. That's not true. I tested it with 5M iterations and they both gave the same results, 0.

Alex Pekka may also mean that the actual writing of lowercase booleans is faster. That makes sense, having to use less keys. The difference is tiny, though. Sorry, I accidentally voted down after after I voted up for you. Lovely, eh? Show 1 more comment.