double question mark operator means “if null “. Take the following expression, for example. String a = b ?? ‘hello’; This means a equals b , but if b is null then a equals ‘hello’ .4 Oca 2019
Read moreWhat does two question marks together mean?
If double question marks are uses it is to emphasise something in return, usually from the shock of the previous thing said . For example, if I said: ‘My dog just died’ (sad, but used for example…) Someone may reply.
Read moreWhat does double question mark mean in laravel?
operator known as Null Coalescing Operator . It returns its first operand if it exists and is not NULL; otherwise, it returns its second operand. It evaluates from left to right.
Read moreWhat is double question mark react?
Conclusion. The JavaScript double question mark is also known as the nullish coalescing operator. It’s an operator that simply returns the right-side expression when the left side expression is either null or undefined .
Read moreCan I have an if statement in an if statement?
A nested if statement is an if statement placed inside another if statement . Nested if statements are often used when you must test a combination of conditions before deciding on the proper action.
Read moreWhat is the process of IF statement?
An if statement checks a boolean value and only executes a block of code if that value is true . To write an if statement, write the keyword if , then inside parentheses () insert a boolean value, and then in curly brackets {} write the code that should only execute when that value is true .
Read moreHow do you declare a variable in darts?
In Dart, a variables must be declared before they are used. Variables are declared using the var keyword followed by variable name that you want to declare . Dart is a type inferred language, which allows compiler automatically infer(know) the type of data we want to store based on the initial value we assign.
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