What you’re experiencing is commonly known as “variable shadowing”. When you use := with any variable in an inner scope, including in statements like if and for despite the lack of braces, a new value and type are associated with that variable: n := “Example” //Prints the string variable `n` to standard output and // … Read more
You can declare a session variable in this way : SET @myvarname := ‘value’; or a local variable in this way : DECLARE my_variable varchar(30) also: DECLARE my_variable varchar(30) DEFAULT ‘value’
You cannot assign to arrays so basically you cannot do what you propose but in C99 you can do this: CGFloat *components; components = (CGFloat [8]) { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.15 }; the ( ){ } operator is called the compound literal operator. It is a C99 feature. Note that in … Read more
Quite simply, JavaScript variables do not have types. The values have types. The language permits us to write code like this: var foo = 42; foo = ‘the answer’; foo = function () {}; So it would be pointless to specify the type in a variable declaration, because the type is dictated by the variable’s … Read more
Long story short; goto will result is a runtime jump, variable definition/declaration will result in storage allocation, compile time. The compiler will see and decide on how much storage to allocate for an int, it will also make so that this allocated storage will be set to 3 when “hitting” i = 3;. That memory … Read more
How about this… double GetTheNumber() { // get the important number from somewhere } And then elsewhere… var theNumber = GetTheNumber(); DoSomethingImportant(theNumber / 5); And then, at some point in the future, somebody notices that GetTheNumber only ever returns whole numbers so refactors it to return int rather than double. Bang! No compiler errors and … Read more
The fact that this rule is applicable in your case is not deliberate: It’s ultimately a result of keeping the grammar simple. There is no incentive to prohibit declarations such as yours, but there are great disincentives to complicate rules, especially if those are intricate as they are. In short, if you don’t want to … Read more
This is actually a fairly interesting question. It’s not as simple as it looks at first. For reference, I’m going to be basing this off of the latest C11 language grammar defined in N1570 I guess the counter-intuitive part of the question is: if this is correct C: if (a == 1) { int b … Read more
x is defined at the left of =. so in x[x], [x] refer to the global one, whereas in x = x;, x hides the global x and initializes from itself -> UB.
The global declaration is when you declare that times is global def timeit(): global times # <- global declaration # … If a variable is declared global, it can’t be used before the declaration. In this case, I don’t think you need the declaration at all, because you’re not assigning to times, just modifying it.