Prolog “or” operator, query

you can ‘invoke’ alternative bindings on Y this way: Note the parenthesis are required to keep the correct execution control flow. The ;/2 it’s the general or operator. For your restricted use you could as well choice the more idiomatic that on backtracking binds Y to each member of the list. edit I understood with …

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OCaml mod function returns different result compared with %

Python is a bit different in its usage of the % operator, which really computes the modulo of two values, whereas other programming languages compute the remainder with the same operator. For example, the distinction is clear in Scheme: In Python: But in OCaml, there’s only mod (which computes the integer remainder), according to this table and as stated in the documentation: Of course, you can implement …

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Using OR operator in a jQuery if statement

Think about what means. || means “or.” The negation of this is (by DeMorgan’s Laws): In other words, the only way that this could be false is if a state equals 10, 15, and 19 (and the rest of the numbers in your or statement) at the same time, which is impossible. Thus, this statement will always be true. State 15 …

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What are the double colons (::) in R?

As you probably have looked up the help page by now usage of :: helps to access the exact function from that specific package. When you load dplyr you probably got a message as follows.. So, for instance, if you would like to use intersect function from dplyr or base package, you need to specify using the :: double colons. Usage will be …

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Difference between “and” and && in Ruby?

and is the same as && but with lower precedence. They both use short-circuit evaluation. WARNING: and even has lower precedence than = so you’ll usually want to avoid and. An example when and should be used can be found in the Rails Guide under “Avoiding Double Render Errors“.