I have exported a function to set random color, which returns me a random color for every call.
like,
exports.getRandomColor = function(index) {
//return random color
}
If I put function like this I can be able to get access to that function from another file. But not inside the same file. (i.e) This getRandomColor is not get accessed in the same file,
It works good if I use
function getRandomColor(index) {
//return random color
}
The problem is I cannot able to access this on another file. Suggestions are welcome.
Thanks in advance
So you can have the next in your file
// define named function
function getRandomColor(index) {
return random color
}
// assign it to the exports, like below
exports.getRandomColor = getRandomColor
Then you can reuse this function whenever you want.
Related
How can I import/require a file, and then use the functions in the file natively?
Say I have file 1:
const file2 = require("./file2.js")
const text = "hello"
file2.print()
And in file 2 I have:
module.exports = {
print:()=>{
console.log(text)
}
}
I want to be able to use functions from another file as if they were in the original file, retaining the variables and objects created in the first file, is this possible?
No, the modules are separate, unless you resort to assigning your variables into the global object and hoping that you can keep track of them without going insane. Don't do that.
Either
pass the data you need around (the best option most of the time), or
maybe add a third module containing the shared state you need and require() it from both file 1 and file 2
No!
But
The regular pattern of shared context is that you create a context and share it. The most simple form of it is something like this:
//In file 1 -->
let myContext = {
text: 'hello'
}
file2.print(myContext);
//In file 2 -->
module.exports = {
print:(ctx)=>{
console.log(ctx.text)
}
}
However
JS has some inbuilt support for context. Something like this:
//In file 1 -->
let myContext = {
text: 'hello'
}
let print = file2.print.bind(myContext);
print();
//In file 2 -->
module.exports = {
print: function(){
console.log(this.text)
}
}
Notice the removal of the argument and changing the arrow function to a function expression.
I am completely new to Dialogflow and nodejs. I need to get the entity value from the argument to the function (agent) and apply if the condition on that. How can I achieve this?
I am trying below but every time I get else condition become true.
I have created an entity named about_member.
function about_member_handeller(agent)
{
if(agent.about_member=="Tarun")
{
agent.add('Yes Tarun');
}
else
{
agent.add("No tarun");
}
}
Please help.
In such cases, you may use console.log to help unleash your black box, like below:
function about_member_handeller(agent) {
console.log(JSON.stringify(agent, null, 2));
if(agent.about_member=="Tarun") {
agent.add('Yes Tarun');
}
else {
agent.add("No tarun");
}
}
JSON.stringfy() will serialize your json object into string and console.log will print the same on the stdOut. So once you run your code this will print the object structure for agent and after which you will know on how to access about_member. Because in the above code it's obvious that you are expecting about_member to be a string, but this code will let you know on the actual data in it and how to compare it.
To get the parameter you can use the following;
const valueOfParam = agent.parameters["parameterName"];
I want to use global variables in my project, but they don't work and I don't understand why they don't work. I'm trying to use them in the following way:
global.connection=null;
function create_connection(connection) {
connection=12345;
}
create_connection(global.connection);
console.log(global.connection); // returns null, why doesn't it return 12345?
Javascript always passes variables by value. So in your case you change the string value without keeping reference to global object.
You could have done this instead
function create_connection(global) {
global.connection=12345;
}
create_connection(global);
I copied the code from kraken. I don't understand why there is a space between get and app(). Can someone please explain what's going on here?
var kraken = {
get app() {
return this._app;
},
use: function (route, delegate) {
//.....
}
}
No, in javascript a function cannot contain spaces. The code you are showing is using the get keyword to bind a property to a object.
get
Binds an object property to a function that will be called when that property is looked up.
Have a look to getters and setters in javascript.
It's a getter.
Check out this link.
The function is get and it's exposing a property called app.
I'm trying to write a Greasemonkey script for a hierarchy of websites such that I have a bunch of code modifications for http://www.foo.com/*, then more specific ones for http://www.foo.com/bar/*, and still others for http://www.foo.com/foobar/*.
Is there anyway for me to write all these in the same script, or do I have to make multiple?
Is there anyway for me to write all
these in the same script, or do I have
to make multiple?
Yes, just use those three #includes, then in your user script do something like (depends on specifics of script):
var currentURL = (document.location+'');
if (currentURL .match(/http:\/\/www\.foo\.com\/foobar\/.*/)) {
// do stuff for page set A
} else if (currentURL .match(/http:\/\/www\.foo\.com\/foo\/.*/)) {
// do stuff for page set B
} else if (currentURL .match(/http:\/\/www\.foo\.com\/.*/)) {
// do stuff for page set C
}
One nifty trick I was shown for dealing with different functions at different sub-locations is to use the global directory of function names as a sort of virtual switchboard...
// do anything that is supposed to apply to the entire website above here.
var place = location.pathname.replace(/\/|\.(php|html)$/gi, "").toLowerCase();
// the regex converts from "foo/" or "foo.php" or "foo.html" to just "foo".
var handler;
if ((handler = global["at_" + place])) {
handler();
}
// end of top-level code. Following is all function definitions:
function at_foo() {
// do foo-based stuff here
}
function at_foobar() {
// do foobar stuff here.
}