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#ObjectScript

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InterSystems ObjectScript is a scripting language to operate with data using any data model of InterSystems Data Platform (Objects, Relational, Key-Value, Document, Globals) and to develop business logic for serverside applications on InterSystems Data Platform.

Documentation.

First-class functionwiki

In computer science, a programming language is said to have first-class functions if it treats functions as first-class citizens. This means the language supports passing functions as arguments to other functions, returning them as the values from other functions, and assigning them to variables or storing them in data structures. Some programming language theorists require support for anonymous functions (function literals) as well. In languages with first-class functions, the names of functions do not have any special status; they are treated like ordinary variables with a function type.

This post continues the article “Declarative development in Caché”.

[2, 3, 5, 7, 11, 13, 17].forEach(function(i) {
  console.log(i);
});

How to do something like this in Caché using COS?

Below are some exercises on this topic.

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So I know it's been a while, and I hate to let my adoring fans down... just not enough to actually start writing again. But the wait is over and I'm back! Now bask in my beautiful ginger words!

For this series, I am going to look at some common problems we see in the WRC and discuss some common solutions. Of course, even if you find a solution here, you are always welcome to call in and expression you gratitude, or just hear my voice!

This week's common problem: "My query returns no data."

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When there's a performance issue, whether for all users on the system or a single process, the shortest path to understanding the root cause is usually to understand what the processes in question are spending their time doing. Are they mostly using CPU to dutifully march through their algorithm (for better or worse); or are they mostly reading database blocks from disk; or mostly waiting for something else, like LOCKs, ECP or database block collisions?

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Moving over from Studio To VSCode like many other will do now the ObjectScript plugin reached version 1.0, I noticed I was missing some items in the objectscript explorer. For example when creating a Rest API using the spec first approach, 3 classes are generated, an application.impl, application.disp and application.spec class, but the disp class was missing in the Object Explorer.

As the application.disp is a generated class, for showing these classes you need to turn this on by hitting the switch on the object explorer:

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Article
· Jul 25, 2019 1m read
Disabling an Ensemble Production

I'm not saying that this is in anyway "best practices," but I'm in a peculiar situation where I need to restrict users from starting a "retired" Ensemble Production in a namespace that's been renamed. It's still an "Ensemble-activated" namespace; we need to keep it available for Ensemble Message Viewer access ... fortunately, only for a little while.

It's a bit of a hack ...

Open the Production class in Studio and add the following classmethod:

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Article
· Jul 16, 2024 6m read
Method or Class Method?

For programmers new to ObjectScript, one question will inevitably arise: “What is the difference between methods and class methods?” A typical answer would be: “A class method applies to a class, but a method applies to an instance of that class.” While that answer is correct, it lacks important information on how these methods di

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Suppose you have an application that allows users to write posts and comment on them. (Wait... that sounds familiar...)

For a given user, you want to be able to list all of the published posts with which that user has interacted - that is, either authored or commented on. How do you make this as fast as possible?

Here's what our %Persistent class definitions might look like as a starting point (storage definitions are important, but omitted for brevity):

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Hello Community,

SQL language remains the most practical way to retrieve information stored in a database.

The JSON format is very often used in data exchange.

It is therefore common to seek to obtain data in JSON format from SQL queries.

Below you will find simple examples that can help you meet this need using ObjectScript and Python code.

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Hi ObjectScript developers!

How to Protect Your Belongings from Pests While Moving - Delicate ...

InterSystems ObjectScript is perhaps the best language on the planet to deal with globals - and it is an interpretable language.

Yes, it has a compiler. But even the compiler can compile some lines in ObjectScript which will then fire as bugs during the runtime.

There are some technics on how to avoid that such as unit testing, coding guidelines and your coding experience, of course ;)

Here I want to present to you the yet another approach to how you can reduce the number of errors in your ObjectScript runtime and enforce coding guidelines - it's an ObjectScript Quality tool developed by Lite Solutions, InterSystems solution partner.

See the details below.

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Article
· Jan 16, 2021 3m read
Creating and listing XData definitions

Hi InterSystems Community!

The ObjectScript language of InterSystems IRIS has the ability to extend classes using a very interesting feature called XData.

It is a section in your class that can be used to create custom definitions to be used within the class itself and also externally.

To create one or more XData definitions for your class is very easy, see the example:

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This is a series of programming challenges for beginners and experienced Caché programmers.

For an introduction : goto to article https://community.intersystems.com/post/advent-code-2016-day1-no-time-ta...

The challenge of day 5 is to calculate a password of 8 characters by finding the MD5 hash of the input and an increasing integer index.
The password is constructed by taking the 6th character of the first 8 hashes that start with 5 zeroes (in hex representation).

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Have you ever needed a math function but could not find what you needed and ended up writing your own? Look no further! ObjectScript-Math is here to solve all your math related function needs.

ObjectScript-Math is an Open Source library for ObjectScript Math functions. It is now available on Open Exchange. This library contains a mix of new functions that are not currently available and functions that are available. The existing functions will be wrapped for use from ObjectScript-Math so that all Math functions can have a central location.

This library will continue to grow, so give it a try and give your feedback!

Don't see what you are looking for? Please feel free to submit requests for additional functions or contribute code yourself!

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This is a series of programming challenges for beginners and experienced Caché programmers.

For an introduction : go to article https://community.intersystems.com/post/advent-code-2016-day1-no-time-ta...

The challenge today is about some basic cryptography : you will have to generate data for a one-time pad (OTP) (see https://en.wikipedia.org/wiki/One-time_pad for more info).

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This is a series of programming challenges for beginners and experienced Caché programmers.

For an introduction : go to article https://community.intersystems.com/post/advent-code-2016-day1-no-time-ta...

Today's challenge is a variation on the White Elephant gift exchange (https://en.wikipedia.org/wiki/White_elephant_gift_exchange), in this case, by a bunch of Elves where only one can have all gifts.

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Recently I needed a classmethod that returns annotation value based on a name of a activity.

As doing it at runtime seemed inefficient, I wrote compile-time utility that iterates over all business process activities and generates relevant code.

This code could be used in a variety of situations when you need to iterate over business process activities, just add it as a secondary superclass to your BPL processes.

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NewBie's Corner Session 4 The Plus Sign and Concatenation Operators

Welcome to NewBie's Corner, a weekly or biweekly post covering basic Caché Material.

Click on the Caché Cube in your system tray and select Terminal to try out the commands.

Plus Sign (+) operator

Typically, the Plus sign (+) adds two numbers together. This is true in COS (Caché ObjectScript), but COS uses it in other ways as well.

Set the variable X to a value of +12

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InterSystems FAQ rubric

ObjectScript allows you to pass any number of arguments using arrays. Do it by adding ... after the argument name.

An example is as follows. In the example statement, the argument information is set in a global variable (a variable stored in the database) so that it can be easily checked after the method is executed.

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InterSystems technologies are renowned for their high performing databases, which support the systems and operations of many organisations. However a key ingredient to this success is the quality and maintainability of their code.

The quality of code can impact everything from speed and ease of fixing bugs and making enhancements, to the overall performance of your organization and your ability to get ahead in the marketplace.

By ensuring your code is maintainable, you can reduce approximately 75% of the systems life cycle costs*. This is why, at George James Software, the solutions we build are always straightforward and written in high quality code - because we know that this solid foundation can positively impact the rest of your organization.

With a maintainable system you're able to reduce your overall maintenance as any issues that occur are significantly faster to identify and fix. This means you're free to allocate that time and budget to enhancements, enabling you to get the most value out of your applications and ultimately better support your organization.

Keep an eye out for our next few posts about what a maintainable system looks like and the tools that can help you keep your code maintainable, in order to help you to reduce those maintenance costs.

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Here in %SYS, we have already examined users, resources, and roles. Now that we know how to set all of that up, we should give it a purpose. Next we will talk about applications! As you may expect, we will see various identical class methods defined here that we have seen in the previous classes. However, some of them will have some tiny yet significant differences.

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Article
· Aug 21, 2019 2m read
ToolBox-4-Iris

Hello everyone,
After some work with IRIS we want to share our ToolBox-4-Iris with you.

What is this about?

The ToolBox-4-Iris is an API for IRIS with a collection of handy and useful tools - features that are not available in IRIS, but greatly simplify application development. To save time and effort on the "typical tools" that every developer needs. This includes additional classes, individual methods or even more efficient macros, which are described in the respective packages.

Content

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InterSystems FAQ rubric

Using the Config.Configuration class and SYS.Database class methods, you can create and register a namespace database from the terminal.

Below is a series of execution examples that create database file /CacheDB/AAA/cache.dat and register database AAA and namespace AAA in the configuration file (cache.cpf).
* Execute in the %SYS namespace. *

* Make sure that this script runs as the user that is used for all IRIS processes to ensure that the directory has appropriate ownership and permissions *

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