if (boolean == false) vs. if (!boolean) [duplicate]
Apart from “readability”, no. They’re functionally equivalent. (“Readability” is in quotes because I hate == false and find ! much more readable. But others don’t.)
boolean-logic
Boolean Implication
Boolean implication A implies B simply means “if A is true, then B must be true”. This implies (pun intended) that if A isn’t true, then B can be anything. Thus: False implies False -> True False implies True -> True True implies False -> False True implies True -> True This can also be … Read more
Makefile ifeq logical AND
Although Hasturkun’s solution will work, I think the idiomatic way to write this is: ifeq ($(TEST_FLAG),TRUE) ifeq ($(DEBUG_FLAG),FALSE) # Stuff endif endif
Should I always use the AndAlso and OrElse operators?
From MSDN: Short-Circuiting Trade-Offs Short-circuiting can improve performance by not evaluating an expression that cannot alter the result of the logical operation. However, if that expression performs additional actions, short-circuiting skips those actions. For example, if the expression includes a call to a Function procedure, that procedure is not called if the expression is short-circuited, … Read more
How to use boolean ‘and’ in Python [duplicate]
Try this: i = 5 ii = 10 if i == 5 and ii == 10: print “i is 5 and ii is 10” Edit: Oh, and you dont need that semicolon on the last line (edit to remove it from my code).
How do I test if a variable does not equal either of two values?
Think of ! (negation operator) as “not”, || (boolean-or operator) as “or” and && (boolean-and operator) as “and”. See Operators and Operator Precedence. Thus: if(!(a || b)) { // means neither a nor b } However, using De Morgan’s Law, it could be written as: if(!a && !b) { // is not a and is … Read more
Why are JavaScript negative numbers not always true or false?
In the first two cases, the boolean is cast to a number – 1 for true and 0 for false. In the final case, it is a number that is cast to a boolean and any number except for 0 and NaN will cast to true. So your test cases are really more like this: … Read more
Naming of TypeScript union and intersection types
Here’s another way to think about it. Consider four sets: Blue things, red things, big things, and small things. If you intersect the set of all blue things and all small things, you end up with the union of the properties — everything in the set has both the blue property and the small property. … Read more
False or None vs. None or False
The expression x or y evaluates to x if x is true, or y if x is false. Note that “true” and “false” in the above sentence are talking about “truthiness”, not the fixed values True and False. Something that is “true” makes an if statement succeed; something that’s “false” makes it fail. “false” values … Read more