Why does PHP log in both lowercase and uppercase?

Question

Is there a difference between trueand trueor falseand falsein PHP?

Answer 1

http://php.net/manual/en/language.types.boolean.php

To specify a logical literal, use the keywords TRUE or FALSE. Both are case insensitive.

Answer 2

Constants are case sensitive by default. But for symmetry with other identifier namespaces, they can be case-insensitive:

 define("mixedCASE", 123, TRUE);

 print MiXeDcAsE;

And just as TRUEthey FALSEwere previously announced. (They are not parsers / languages.)

Answer 3

JSON, RFC7159 :

. .

Php 5.6:

json_decode() JSON, , true, false null , JSON

PSR-2 :

PHP- .

PHP true, false null .

Ps.: RFC7159 - SO.

Answer 4

, PHP Parser , TRUE, true FALSE, false