Each event loop has a microtask queue and a macrotask queue. A microtask is a task that is originally to be queued on the microtask queue rather than a task queue. Refer to https://www.w3.org/TR/html51/webappapis.html#microtask-queue. There are two kinds of microtasks: solitary callback microtasks, such as Promise， and compound microtasks, such as Object.observe, MutationObserver and process.nextTick … Read more
You’re correct that it cannot guarantee uniqueness, however there are approximately 3.402823669209387e+38 different values in a 32 digit hex value (16^32). That means that, assuming the math behind the algorithm gives a good distribution, your odds are phenomenally small that there will be a duplicate. You do have to keep in mind that it IS … Read more
I’ve come across this issue a lot of times too and ended up using interfaces. I think it’s important to drop the idea that C# is any form, or even an evolution of C++. They’re two different languages that share almost the same syntax. I usually express ‘const correctness’ in C# by defining a read-only … Read more
Given an arbitrary function, f, we define a function f’ which returns 1 on input n if f halts on input n. Now, for some number x we define a function g which, on input n, returns 1 if n = x, and otherwise calls f'(n). If functional equivalence were decidable, then deciding whether g … Read more
Schemas logically group tables, procedures, views together. All employee-related objects in the employee schema, etc. You can also give permissions to just one schema, so that users can only see the schema they have access to and nothing else.
Unfortunately, no As i’m sure you’re aware, but I’ll state explicitly for completeness – there are only the 2 keywords to control the method invocation: this – this.method() – looks for method starting from the invoking instance’s class (the instance’s “top” virtual table – implied default) super – super.method() – looks for method starting from … Read more
Set.retainAll() is how you find the intersection of two sets. If you use HashSet, then converting your ArrayLists to Sets and using retainAll() in a loop over all of them is actually O(n).
The term “referential transparency” comes from analytical philosophy, the branch of philosophy that analyzes natural language constructs, statements and arguments based on the methods of logic and mathematics. In other words, it is the closest subject outside computer science to what we call programming language semantics. The philosopher Willard Quine was responsible for initiating the … Read more
A Y-combinator is a “functional” (a function that operates on other functions) that enables recursion, when you can’t refer to the function from within itself. In computer-science theory, it generalizes recursion, abstracting its implementation, and thereby separating it from the actual work of the function in question. The benefit of not needing a compile-time name … Read more
Well macros don’t directly expand recursively, but there are ways we can work around this. The easiest way of doing recursion in the preprocessor is to use a deferred expression. A deferred expression is an expression that requires more scans to fully expand: #define EMPTY() #define DEFER(id) id EMPTY() #define OBSTRUCT(…) __VA_ARGS__ DEFER(EMPTY)() #define EXPAND(…) … Read more