小编Juh*_*nen的帖子

有没有简洁的方法来检查是否设置了变量,然后回显它而不重复相同的变量名称？

而不是这个:

<?php
    if(!empty($this->variable)) {
        echo '<a href="', $this->variable, '">Link</a>';
    }
?>

我正在考虑这种C风格的伪代码:

<?php
    echo if(!empty($this->variable, '<a href="', %s, '">Link</a>'));
?>

PHP有sprintf,但它并没有完全按我所希望的那样做.如果当然我可以用它来制作一个方法/功能,但肯定必须有一种"本地"的方法吗？

更新:$this->variable如果我理解,三元操作也会重复这一部分？

echo (!empty($this->variable) ? '<a href="',$this->variable,'">Link</a> : "nothing");

一段时间后回到Java,我正在尝试使用命令行在Java 8,Jersey 2.27和Jetty 9.4.9上使用简单的RESTful API.该应用程序确实有效,但我不断收到数百条警告:

2018-04-27 01:17:24.845:WARN:oeja.AnnotationParser:main: Unrecognized runtime asm version, assuming 393216
2018-04-27 01:17:24.945:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.ArrayELResolver scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/ArrayELResolver.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/ArrayELResolver.class
2018-04-27 01:17:24.949:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.BeanELResolver$BeanProperties scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/BeanELResolver$BeanProperties.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/BeanELResolver$BeanProperties.class
2018-04-27 01:17:24.952:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.BeanELResolver$BeanProperty scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/BeanELResolver$BeanProperty.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/BeanELResolver$BeanProperty.class
2018-04-27 01:17:24.954:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.BeanELResolver scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/BeanELResolver.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/BeanELResolver.class
2018-04-27 01:17:24.959:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.CompositeELResolver scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/CompositeELResolver.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/CompositeELResolver.class
2018-04-27 01:17:24.961:WARN:oeja.AnnotationParser:qtp988458918-12: javax.el.ELContext scanned from multiple locations: jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/el-api-2.2.jar!/javax/el/ELContext.class, jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/el/ELContext.class
2018-04-27 01:17:24.962:WARN:oeja.AnnotationParser:qtp988458918-15: javax.annotation.Generated scanned from multiple locations: jar:file:///paste4j/deployment/jetty-runner-9.4.9.v20180320.jar!/javax/annotation/Generated.class, jar:file:///tmp/jetty-0.0.0.0-8081-paste4j.war-_-any-8355640322316327743.dir/webapp/WEB-INF/lib/javax.annotation-api-1.2.jar!/javax/annotation/Generated.class
2018-04-27 01:17:24.962:WARN:oeja.AnnotationParser:qtp988458918-15: …

我不太确定如何将这个简单的旧 Flask-Script manage.py迁移到 Flask 0.11+ 中提供的 CLI

from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand

from app import app, db

migrate = Migrate(app, db)
manager = Manager(app)

manager.add_command('db', MigrateCommand)


if __name__ == "__main__":
    manager.run()

它是这样使用的，与 Flask Migrate 一起使用：

python manage.py db migrate

按照Flask 2.x 文档，我可以获得：

import click
from flask_migrate import Migrate, MigrateCommand

from app import app, db

@app.cli.command("db")
@click.argument("migration_command")
def handle_command(migration_command):
    print("Handling command {}".format(migration_command))

但运行时：

python manage.py db migrate

但它似乎handle_command从未被调用，并且该db migrate命令似乎没有运行。

另外，Flask …

为什么这样做：（有效 = 每个代表文本都出现在前一个下方）

    Column {
        Repeater {
            model: ['test1', 'test2', 'test3']
            delegate: Text {
                text: modelData
            }
        }
    }

但这打破了布局，因为每个文本都出现在彼此之上：

    Column {
        Repeater {
            model: ['test1', 'test2', 'test3']
            delegate: Item {
                Text {
                    text: modelData
                }
            }
        }
    }

如果我创建一个单独的组件，也会发生同样的事情：

我的文本项.qml

import QtQuick 2.5

Item {
    property string myText: ''
    Text {
       text: myText
    }
}

进而：

    Column {
        Repeater {
            model: ['test1', 'test2', 'test3']
            delegate: MyTextItem {
                myText: modelData
            }
        }
    }

我遇到了一个不幸的情况,其中一个特定文件的文件名是Python中的关键字.有没有办法在没有重命名文件的情况下"绕过"这个？

libraries/import.py 有功能 my_function()

from libraries.import import my_function

得到:

E999 - SyntaxError: invalid syntax 

并指向" .import"部分

我试了几件事:

from "libraries.import" import my_function
from libraries."import" import my_function
from libraries import import.my_function
from repr(libraries.import) import my_function
from `libraries.import` import my_function  # deprecated
import libraries.import.my_function

但它们都有相同的结果:SyntaxError.

也无法在Python手册中找到任何提示 - 但也没有关于使用保留名称的警告:)这可能吗？怎么样？