Canon | matching output from a command across hosts

The thing the compiler is looking for is a lifetime bound. A lifetime bound of 'a doesn't mean “this type is a reference with lifetime 'a”, but rather “all of the references this type contains have lifetimes of at least 'a”.

(When a lifetime bound is written explicitly, it looks like where T: 'a.)

Thus, any type which does not contain any references (or rather, has no lifetime parameters) automatically satisfies the 'static lifetime bound. If T: 'static, then Arc: 'static (and the same for Box and Rc).

How could Arc::clone(&msg) get a 'static lifetime? The value it points to isn't known at compile-time, and could die before the whole program exits.

It does not point to the value using a reference, so it's fine. The type of your value is Arc>; there are no lifetime parameters here because there are no references. If it were, hypothetically, Arc<'a, Mutex> (a lifetime parameter which Arc doesn't actually have), then that type would not satisfy the bound.

The job of Arc (or Rc or Box) is to own the value it points to. Ownership is not a reference and thus not subject to lifetimes.

However, if you had the type Arc<&'a str>> then that would not satisfy the bound, because it contains a reference which is not 'static.

Define dependencies(The random generator here) as local variables are not recommended, it's much harder to do dependencies injection(Or it won't be possible), so I change the functions Rng_t into template function and pass the Rng as a parameter.

In practice to construct a random generation may be heavy work, it needs to initialize its internal status, to construct it every time we call the function flipCoin is waste.

The non-virtual function can be mocked, one most commonly used strategy is to use the template, here we make the class CoinFlipper's member function as a template function, then we can test the dependency with our MockRng.

Be aware that for the template function, we need to define the member function in the header file.

coinflipper.h:

You can create a new message from transformed and remove headers you don't need

This one should be just two steps, split and replace.

Reference to this document, you can use the publisher and type for your custom script like this.

Check:

1. That you are connecting to the public IP of the EC2.
2. That you do not have any restriction on your NACL (Network Access Lists)

If you're going to assign different roles to different nodes, those nodes cannot use the same configuration. The easiest way to accomplish this is through n1 having "testRole1" in its akka.cluster.roles list and n2 having "testRole2" in its akka.cluster.roles list.

Everything in akka.cluster config is only configuring that node for participation in the cluster (it's configuring the cluster component on that node). A few of the settings have to be the same across the nodes of a cluster (e.g. the SBR settings), but a setting on n1 doesn't affect a setting on n2.

By looking where a "ld.exe" was present in C:\Android\android_sdk\ndk-bundle\toolchains\llvm folder, I found some under C:\Android\r21a_Qt5_14\android_sdk\ndk-bundle\toolchains\llvm\prebuilt\windows-x86_64\\bin so I concluded that target platform was probably missing.

I added:

There is no naming convention in JavaScript to differentiate between pure functions and functions with side-effects.

It doesn't mean you shouldn't have one for your project though. I think it is a good idea.

A possible first approach is following the command–query separation principle, that states that only pure functions (queries) return values, while functions with side-effects (commands) do not.

Then you can look at existing languages following a similar convention.

In Scheme and Ruby (inspired by Scheme) functions causing side-effects end in ! (e.g. set-car!) and predicates end in ? (e.g. number?).

From https://www.cs.cmu.edu/Groups/AI/html/r4rs/r4rs_3.html#SEC14:

By convention, the names of procedures that always return a boolean value usually end in "`?'". Such procedures are called predicates.

By convention, the names of procedures that store values into previously allocated locations (see section Storage model) usually end in "`!'". Such procedures are called mutation procedures. By convention, the value returned by a mutation procedure is unspecified.

Unfortunately you can't use ! and ? as part of a function name in JavaScript.

In Common Lisp, predicates end in p (e.g. EVENP) and destructive functions start with n (that stands for non-consing), e.g. REVERSE vs NREVERSE. While possible and compact, I don't find this particularly appealing.

Some languages use imperative and past verbs. Think about python's sort (in-place) vs sorted (functional).

Swift's API Design Guidelines is explicit about it:

Name functions and methods according to their side-effects

Those without side-effects should read as noun phrases, e.g. x.distance(to: y), i.successor().

Those with side-effects should read as imperative verb phrases, e.g., print(x), x.sort(), x.append(y).

Name Mutating/nonmutating method pairs consistently. A mutating method will often have a nonmutating variant with similar semantics, but that returns a new value rather than updating an instance in-place.

When the operation is naturally described by a verb, use the verb’s imperative for the mutating method and apply the “ed” or “ing” suffix to name its nonmutating counterpart.

Mutating: x.sort()

Nonmutating: z = x.sorted()

Mutating: x.append(y)

Nonmutating: z = x.appending(y)

Prefer to name the nonmutating variant using the verb’s past participle (usually appending “ed”):