JavaScript Dev

JavaScript Dev

1605680880

A Vanilla.js Package to Convert a Nested List Into a Tree Menu

A tiny package to easily create a tree menu.

Example Usage

Include listree.min.css and listree.min.umd.js in the header and footer respectively. Make sure that the unordered list in the html has class-markers like below (Should be easy to generate via any server side templating language. ). Then just invoke listree(). It will scan the document for the class markers and convert the ul list into a tree

<!DOCTYPE html>
<html>
  <head>
    <link rel="stylesheet" href="https://unpkg.com/listree/dist/listree.min.css"/>
    <title>LisTree</title>
  </head>
  <body>
    <ul class="listree">
        <li>
            <div class="listree-submenu-heading">Metrics</div>
            <ul class="listree-submenu-items">
                <li>
                    <div class="listree-submenu-heading">Daily Metrics</div>
                    <ul class="listree-submenu-items">
                    <li>
                        <div class="listree-submenu-heading">Daily Order Metrics</div>
                        <ul class="listree-submenu-items">
                        <li>
                            <div class="listree-submenu-heading">Categorywise Daily order metrics</div>
                            <ul class="listree-submenu-items">
                                <li>
                                    <a href="">Categorywise daily order count</a>
                                </li>
                                <li>
                                    <a href="">Categorywise daily bookings</a>
                                </li>
                            </ul>
                        </li>
                        <li>
                            <div class="listree-submenu-heading">Storewise Daily order metrics</div>
                            <ul class="listree-submenu-items">
                                <li>
                                    <a href="">Storewise daily order count</a>
                                </li>
                            </ul>
                        </li>
                        </ul>
                    </li>
                    <li>
                        <div class="listree-submenu-heading">Daily Invoice Metrics</div>
                        <ul class="listree-submenu-items">
                            <li>
                                <div class="listree-submenu-heading">Categorywise Daily invoice metrics</div>
                                <ul class="listree-submenu-items">
                                    <li>
                                        <a href="">Categorywise daily invoice count</a>
                                    </li>
                                </ul>
                            </li>
                            <li>
                                <div class="listree-submenu-heading">Storewise Daily invoice metrics</div>
                                <ul class="listree-submenu-items">
                                    <li>
                                        <a href="">Storewise daily invoice count</a>
                                    </li>
                                    <li>
                                        <a href="">Storewise daily revenue</a>
                                    </li>
                                </ul>
                            </li>
                        </ul>
                    </li>
                    </ul>
                </li>
                <li>
                    <div class="listree-submenu-heading">Monthly Metrics</div>
                    <ul class="listree-submenu-items">
                        <li>
                            <div class="listree-submenu-heading">Monthly Order Metrics</div>
                            <ul class="listree-submenu-items">
                                <li>
                                    <div class="listree-submenu-heading">Categorywise Monthly order metrics</div>
                                    <ul class="listree-submenu-items">
                                        <li>
                                            <a href="">Categorywise monthly order count</a>
                                        </li>
                                    </ul>
                                </li>
                                <li>
                                    <div class="listree-submenu-heading">Storewise Monthly order metrics</div>
                                    <ul class="listree-submenu-items">
                                        <li>
                                            <a href="">Storewise monthly order count</a>
                                        </li>
                                    </ul>
                                </li>
                            </ul>
                        </li>
                    </ul>
                </li>
            </ul>
        </li>
        <li>
            <div class="listree-submenu-heading">Settings</div>
            <ul class="listree-submenu-items">
                <li>
                    <div class="listree-submenu-heading">Personal Settings</div>
                    <ul class="listree-submenu-items">
                        <li><a href="">Password Settings</a></li>
                        <li><a href="">Viewing Preferences</a></li>
                    </ul>
                </li>
                <li>
                    <div class="listree-submenu-heading">Org Settings</div>
                    <ul class="listree-submenu-items">
                        <li><a href="">Teams</a></li>
                        <li><a href="">Billing</a></li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>
    <script src="https://unpkg.com/listree/dist/listree.umd.min.js"></script>
    <script>
        listree();
    </script>
  </body>
</html>

Download Details:

Author: SuryaSankar

Source Code: https://github.com/SuryaSankar/listree

#javascript

What is GEEK

Buddha Community

A Vanilla.js Package to Convert a Nested List Into a Tree Menu

NBB: Ad-hoc CLJS Scripting on Node.js

Nbb

Not babashka. Node.js babashka!?

Ad-hoc CLJS scripting on Node.js.

Status

Experimental. Please report issues here.

Goals and features

Nbb's main goal is to make it easy to get started with ad hoc CLJS scripting on Node.js.

Additional goals and features are:

  • Fast startup without relying on a custom version of Node.js.
  • Small artifact (current size is around 1.2MB).
  • First class macros.
  • Support building small TUI apps using Reagent.
  • Complement babashka with libraries from the Node.js ecosystem.

Requirements

Nbb requires Node.js v12 or newer.

How does this tool work?

CLJS code is evaluated through SCI, the same interpreter that powers babashka. Because SCI works with advanced compilation, the bundle size, especially when combined with other dependencies, is smaller than what you get with self-hosted CLJS. That makes startup faster. The trade-off is that execution is less performant and that only a subset of CLJS is available (e.g. no deftype, yet).

Usage

Install nbb from NPM:

$ npm install nbb -g

Omit -g for a local install.

Try out an expression:

$ nbb -e '(+ 1 2 3)'
6

And then install some other NPM libraries to use in the script. E.g.:

$ npm install csv-parse shelljs zx

Create a script which uses the NPM libraries:

(ns script
  (:require ["csv-parse/lib/sync$default" :as csv-parse]
            ["fs" :as fs]
            ["path" :as path]
            ["shelljs$default" :as sh]
            ["term-size$default" :as term-size]
            ["zx$default" :as zx]
            ["zx$fs" :as zxfs]
            [nbb.core :refer [*file*]]))

(prn (path/resolve "."))

(prn (term-size))

(println (count (str (fs/readFileSync *file*))))

(prn (sh/ls "."))

(prn (csv-parse "foo,bar"))

(prn (zxfs/existsSync *file*))

(zx/$ #js ["ls"])

Call the script:

$ nbb script.cljs
"/private/tmp/test-script"
#js {:columns 216, :rows 47}
510
#js ["node_modules" "package-lock.json" "package.json" "script.cljs"]
#js [#js ["foo" "bar"]]
true
$ ls
node_modules
package-lock.json
package.json
script.cljs

Macros

Nbb has first class support for macros: you can define them right inside your .cljs file, like you are used to from JVM Clojure. Consider the plet macro to make working with promises more palatable:

(defmacro plet
  [bindings & body]
  (let [binding-pairs (reverse (partition 2 bindings))
        body (cons 'do body)]
    (reduce (fn [body [sym expr]]
              (let [expr (list '.resolve 'js/Promise expr)]
                (list '.then expr (list 'clojure.core/fn (vector sym)
                                        body))))
            body
            binding-pairs)))

Using this macro we can look async code more like sync code. Consider this puppeteer example:

(-> (.launch puppeteer)
      (.then (fn [browser]
               (-> (.newPage browser)
                   (.then (fn [page]
                            (-> (.goto page "https://clojure.org")
                                (.then #(.screenshot page #js{:path "screenshot.png"}))
                                (.catch #(js/console.log %))
                                (.then #(.close browser)))))))))

Using plet this becomes:

(plet [browser (.launch puppeteer)
       page (.newPage browser)
       _ (.goto page "https://clojure.org")
       _ (-> (.screenshot page #js{:path "screenshot.png"})
             (.catch #(js/console.log %)))]
      (.close browser))

See the puppeteer example for the full code.

Since v0.0.36, nbb includes promesa which is a library to deal with promises. The above plet macro is similar to promesa.core/let.

Startup time

$ time nbb -e '(+ 1 2 3)'
6
nbb -e '(+ 1 2 3)'   0.17s  user 0.02s system 109% cpu 0.168 total

The baseline startup time for a script is about 170ms seconds on my laptop. When invoked via npx this adds another 300ms or so, so for faster startup, either use a globally installed nbb or use $(npm bin)/nbb script.cljs to bypass npx.

Dependencies

NPM dependencies

Nbb does not depend on any NPM dependencies. All NPM libraries loaded by a script are resolved relative to that script. When using the Reagent module, React is resolved in the same way as any other NPM library.

Classpath

To load .cljs files from local paths or dependencies, you can use the --classpath argument. The current dir is added to the classpath automatically. So if there is a file foo/bar.cljs relative to your current dir, then you can load it via (:require [foo.bar :as fb]). Note that nbb uses the same naming conventions for namespaces and directories as other Clojure tools: foo-bar in the namespace name becomes foo_bar in the directory name.

To load dependencies from the Clojure ecosystem, you can use the Clojure CLI or babashka to download them and produce a classpath:

$ classpath="$(clojure -A:nbb -Spath -Sdeps '{:aliases {:nbb {:replace-deps {com.github.seancorfield/honeysql {:git/tag "v2.0.0-rc5" :git/sha "01c3a55"}}}}}')"

and then feed it to the --classpath argument:

$ nbb --classpath "$classpath" -e "(require '[honey.sql :as sql]) (sql/format {:select :foo :from :bar :where [:= :baz 2]})"
["SELECT foo FROM bar WHERE baz = ?" 2]

Currently nbb only reads from directories, not jar files, so you are encouraged to use git libs. Support for .jar files will be added later.

Current file

The name of the file that is currently being executed is available via nbb.core/*file* or on the metadata of vars:

(ns foo
  (:require [nbb.core :refer [*file*]]))

(prn *file*) ;; "/private/tmp/foo.cljs"

(defn f [])
(prn (:file (meta #'f))) ;; "/private/tmp/foo.cljs"

Reagent

Nbb includes reagent.core which will be lazily loaded when required. You can use this together with ink to create a TUI application:

$ npm install ink

ink-demo.cljs:

(ns ink-demo
  (:require ["ink" :refer [render Text]]
            [reagent.core :as r]))

(defonce state (r/atom 0))

(doseq [n (range 1 11)]
  (js/setTimeout #(swap! state inc) (* n 500)))

(defn hello []
  [:> Text {:color "green"} "Hello, world! " @state])

(render (r/as-element [hello]))

Promesa

Working with callbacks and promises can become tedious. Since nbb v0.0.36 the promesa.core namespace is included with the let and do! macros. An example:

(ns prom
  (:require [promesa.core :as p]))

(defn sleep [ms]
  (js/Promise.
   (fn [resolve _]
     (js/setTimeout resolve ms))))

(defn do-stuff
  []
  (p/do!
   (println "Doing stuff which takes a while")
   (sleep 1000)
   1))

(p/let [a (do-stuff)
        b (inc a)
        c (do-stuff)
        d (+ b c)]
  (prn d))
$ nbb prom.cljs
Doing stuff which takes a while
Doing stuff which takes a while
3

Also see API docs.

Js-interop

Since nbb v0.0.75 applied-science/js-interop is available:

(ns example
  (:require [applied-science.js-interop :as j]))

(def o (j/lit {:a 1 :b 2 :c {:d 1}}))

(prn (j/select-keys o [:a :b])) ;; #js {:a 1, :b 2}
(prn (j/get-in o [:c :d])) ;; 1

Most of this library is supported in nbb, except the following:

  • destructuring using :syms
  • property access using .-x notation. In nbb, you must use keywords.

See the example of what is currently supported.

Examples

See the examples directory for small examples.

Also check out these projects built with nbb:

API

See API documentation.

Migrating to shadow-cljs

See this gist on how to convert an nbb script or project to shadow-cljs.

Build

Prequisites:

  • babashka >= 0.4.0
  • Clojure CLI >= 1.10.3.933
  • Node.js 16.5.0 (lower version may work, but this is the one I used to build)

To build:

  • Clone and cd into this repo
  • bb release

Run bb tasks for more project-related tasks.

Download Details:
Author: borkdude
Download Link: Download The Source Code
Official Website: https://github.com/borkdude/nbb 
License: EPL-1.0

#node #javascript

Einar  Hintz

Einar Hintz

1593229920

Android Menu - Steps to implement Menu in Android - DataFlair

Types of Android Menu

Let us see the various types of menu in Android:

1. Android Options Menu

The Options Menu is a collection of options for an activity. It has a set of items that are useful to perform actions. It helps us to combine multiple actions together.

Following is an example of Options Menu:

Options Menu in Android

2. PopUp Menu

Pop-Up menu is a menu that displays a list of items in a popup window. A pop-up menu appears below the view by default, in case there is no space, it appears above it.

Android Pop Up menu

3. Contextual Menu

A contextual menu is a floating menu. It appears only when the users long-press an element or right clicks on that. It generally affects the selected element.

Contextual menu

#android tutorials #android menu #android menu types #contextual menu #menu android #menu in android #options menu #types of menu in android

Eva  Murphy

Eva Murphy

1625778000

Validatioin in Nest JS and DTO objects | Nest JS Node JS tutorials - 04

In this video, we are going to look at how to do validations of the request coming to the controller. Validating the request object is very important, and I will show you in this video how you can create a DTO and then define rules inside that DTO so that you can run validations.

Github code: https://my-lnk.com/r/2233233755

#nest js #node js #node #nest #javascript #dto

August  Larson

August Larson

1624429860

How to Convert Loops to List Comprehension in Python

Do the same but faster

List comprehension is used for creating lists based on iterables. It can also be described as representing for and if loops with a simpler and more appealing syntax. List comprehensions are relatively faster than for loops.

The syntax of a list comprehension is actually easy to understand. However, when it comes to complex and nested operations, it might get a little tricky to figure out how to structure a list comprehension.

In such cases, writing the loop version first makes it easier to write the code for the list comprehension. We will go over several examples that demonstrate how to convert a loop-wise syntax to a list comprehension.

Basic structure of list comprehension (image by author)

Let’s start with a simple example. We have a list of 5 integers and want to create a list that contains the squares of each item. Following is the for loop that performs this operation.

lst_a = [1, 2, 3, 4, 5]

lst_b = []
for i in lst_a:
   lst_b.append(i**2)
print(lst_b)
[1, 4, 9, 16, 25]

#python #programming #how to convert loops to list comprehension in python #convert loops #list comprehension #how to convert loops to list comprehension

Eva  Murphy

Eva Murphy

1625770260

Introduction to Nest JS - A Node JS Framework - From The Basics

#nodejs #javascript

Let’s talk about Nest JS - a Node JS based progressive framework which comes with a lot of potentials.

It allows great modular code architecture and it comes with a lot of stuff already baked in so that you can start focusing on your idea without wasting too much time.

#nest js #node js #node #nest #javascript