annotations

问题 In python 3.x, it is common to use return type annotation of a function, such as: def foo() -> str: return "bar" What is the correct annotation for the "void" type? I'm considering 3 options: def foo() -> None: not logical IMO, because None is not a type, def foo() -> type(None): using the best syntax I know for obtaining NoneType , def foo(): omit explicit return type information. Option 2. seems the most logical to me, but I've already seen some instances of 1. 回答1: This is straight from

问题 In python 3.x, it is common to use return type annotation of a function, such as: def foo() -> str: return "bar" What is the correct annotation for the "void" type? I'm considering 3 options: def foo() -> None: not logical IMO, because None is not a type, def foo() -> type(None): using the best syntax I know for obtaining NoneType , def foo(): omit explicit return type information. Option 2. seems the most logical to me, but I've already seen some instances of 1. 回答1: This is straight from

问题 I already tried things here https://symfony.com/doc/master/components/routing.html But i couldn't make it. <?php use Doctrine\Common\Annotations\AnnotationReader; use Symfony\Bundle\FrameworkBundle\Routing\AnnotatedRouteControllerLoader; use Symfony\Component\Config\FileLocator; use Symfony\Component\Routing\Loader\AnnotationDirectoryLoader; use Composer\Autoload\ClassLoader; use Doctrine\Common\Annotations\AnnotationRegistry; /** @var ClassLoader $loader */ $loader = require __DIR__.'/vendor

问题 I would like to restrict on which constant value extension function can be called. For example function like: @IdRes fun <T : View> Int.find() = findViewById<T>(this) If this was called on real id, it's fine: R.id.someView.find<TextView>() // ok But this should make compilation error: 42.find<TextView>() // should be compile error Is annotating extension receiver supported in Kotlin? 回答1: As described in the documentation, you can use the following syntax: fun @receiver:IdRes <T : View> Int

问题 This bounty has ended . Answers to this question are eligible for a +50 reputation bounty. Bounty grace period ends in 17 hours . Dmitry wants to draw more attention to this question: I tried to make annotations within this method fig.update_layout( showlegend=False, annotations=[ dict( x=122.58333, y=45.36667, xref="x", yref="y", text="15", showarrow=True, arrowhead=7, ax=0, ay=-40 ) ] ) But here is problem with coordinate system. So I'm stuck here. In the code below I have marker labels.

问题 We use the annotations @javax.annotation.Nullable and @javax.annotation.Nonnull to document the behavior of method parameters. Is it possible to show this annotations in the JavaDoc popup in Eclipse? I means the popup that occur if I move with the mouse over a method. Currently Eclipse show only the annotations of the method self but not of the parameter. 回答1: I'm using Indigo SR1 [Java EE version], and it does exactly this. I didn't configure it specifically, so I think its something that

问题 Python 3.6 supports type annotation, like: def foo() -> int: return 42 But what is expected to use when a function hasn't return anything? PEP484 examples mostly use None as a return type, but there is also NoReturn type from typing package. So, the question is what is preferable to use and what is considered a best practice: def foo() -> None: #do smth or from typing import NoReturn def foo() -> NoReturn: #do smth 回答1: NoReturn means the function never returns a value . The function either

问题 To create a type annotation that is applicable in type contexts, there is no way other than meta-annotating the annotation type with @Target(ElementType.TYPE_USE) . However, this annotation also becomes applicable in declaration contexts due to the bad decision of the Java designers. According to the Java SE documentation, it reads: The constant TYPE_USE corresponds to the type contexts in JLS 4.11, as well as to two declaration contexts: type declarations (including annotation type

问题 To create a type annotation that is applicable in type contexts, there is no way other than meta-annotating the annotation type with @Target(ElementType.TYPE_USE) . However, this annotation also becomes applicable in declaration contexts due to the bad decision of the Java designers. According to the Java SE documentation, it reads: The constant TYPE_USE corresponds to the type contexts in JLS 4.11, as well as to two declaration contexts: type declarations (including annotation type

问题 To create a type annotation that is applicable in type contexts, there is no way other than meta-annotating the annotation type with @Target(ElementType.TYPE_USE) . However, this annotation also becomes applicable in declaration contexts due to the bad decision of the Java designers. According to the Java SE documentation, it reads: The constant TYPE_USE corresponds to the type contexts in JLS 4.11, as well as to two declaration contexts: type declarations (including annotation type