Scripting 101 ? Condition Checking In Different Languages REPACK
ImageJ is able to run scripts written in different languages. Besides all the differences the approach on how to use the API of ImageJ is similar for all of them. This article will introduce the basic concepts and is valid for all scripting languages.
Scripting 101 – Condition Checking in Different Languages
The examples are written in Groovy, which is available with ImageJ2, but not the original ImageJ. It should be straightforward to adapt to other scripting languages supported by ImageJ and/or ImageJ2. For the ImageJ macro language, refer to the dedicated section in Languages.
The command runMacro works only for ijm macro. To call a script written in another scripting languages, one should use the runMacroFile(PathToScript, Arguments) (respectively IJ.runMacroFile of the ImageJ API). Still using the getArgument to pass the variables from mainScript to subScript.
But what is Groovy? Well, Apache Groovy is an object-oriented programming language used for JVM platform. This dynamic language has a lot of features drawing inspiration from Python, Smalltalk & Ruby. It can be used to orchestrate your pipeline in Jenkins and it can glue different languages together meaning that teams in your project can be contributing in different languages.
Groovy can seamlessly interface with the Java language and the syntax of Java and Groovy is very similar. If you forget the syntax when writing Groovy, you can continue to write directly in Java syntax. Groovy can also be used as one of the scripting languages for the Java platform. Groovy scripts can be called in Java, which effectively reduces time spent on Java development.
Groovy also combines the features of Python, Ruby and other scripting languages. It does a lot of syntactic sugar in grammar. When it comes to Java development, there is a lot of code that must be written in Java which can be omitted in Groovy as seen from the previous snippets.
Record/playback systems do generate test scripts behind the scenes but they are typically written in simple scripting languages like VBScript. Advanced users can (and typically will) go in and manipulate the code directly to finetune how a test behaves.
Conditions need to be a single statement that can be evaluated to a Boolean. You can write the entire statement or use a shortened form as it is common in many programming languages. GameState.talkedToNPC can be used instead of GameState.talkedToNPC == true and !GameState.talkedToNPC is the same as GameState.talkedToNPC == false. A whole number of relational operators can be used to compare values. With the help of logical operators we can concatenate multiple comparisons into a condition statement.
The player character Lily is approached by the NPC Mr Starvaz. We want to have different dialogue options available to the player depending on which skills they possess. As we have seen earlier the skills exist as properties in a template, therefore the way to check for them in a condition is a bit different from checking for a variable. As we can see in the comment of this condition node, we want to check if Lily has the conversation skill at least skilled to 1.
Because the condition checking for the Survival property returned true, the story follows the branch leading to more money. Now the credits variable gets updated. 4000 credits, payed up front. Very nice.
The zero for success and any non-zero value for failure seems counterintuitive. In most other programming languages, zero represents false, and one (or greater) represents true. However, in bash scripting, the UNIX convention returns the exit status instead of a truth value, and the two should not be confused.
The elif clause combined with the if else statement creates multiple conditional checks. The if elif creates a series of checks with different results. The syntax is:
An "if" statement is very similar to a Begin/End block. It begins with the keyword "if", followed by the condition which should be checked, and it ends with the keyword "endif". "If" statements are different to Begin/End blocks in that the condition is completely defined by you, as opposed to being chosen from a list of usable conditions. Here is how we will change our script so that the code within the OnAdd block will run when the bobby pin is added to the inventory of any actor, but the message will only be shown if it is added to the player's inventory:
Now, as you can see, our script has pretty much exactly the same functionality as it had previously, although it is slightly less efficient. What we are going to do now is add an alternate section of code that will only run if the scripted item is added to the inventory of a reference other than the player. The most obvious way in which we could do this would be to create a second "if" statement, that checks a different condition:
As you can see, if a bobby pin is added to the inventory of a reference other than the player, the script will then check if the bobby pin has been added to the inventory of the MQDadRef reference. While this will work perfectly, the scripting language used in Fallout 3/New Vegas includes a nifty tool that allows us to use a lot of different conditions together like this without having to nest all of our "if" statements within one another. This tool is known as an "elseif" statement, and can be used like this:
As you can see, the comments here help to explain the true meaning of the conditions. If the comments were absent, then someone reading the script would need to look up the documentation of GetOpenState in order to understand what the conditions really mean. The same concept applies to variables - if you use a variable in which different values represent different states, it is a good idea to use comments when you declare the variable in order to explain what each value represents.
There are a limited number of conditions that can be used for Begin/End blocks, such as OnAdd and OnDeath. Each of these conditions is known as a blocktype. Different types of scripts have different blocktypes available to them, so it can help to think of blocktypes as being split into several categories:
A variable is something that allows you to store information in a script for later use. There are three types of variable available for use in Fallout 3 scripting, each which stores a different type of information.
If you use different testing frameworks (or languages), fear not. With a few tweaks, you should be able to modify the script to suit your needs. In fact, finding something here in Vim script that you can modify or use differently is more in line with the ultimate goal of this case study than simply copy-and-pasting wholesale.
If we want to add conditions and control flow logic, our Vim script starts to look pretty much how we would expect it to look, given the conventions in other modern programming languages. It uses if, elseif, and else.
Where has all this Vim scripting left us? Using maps, we have configured Vim to respond to three simple keystrokes: ta, tf, and tt. These keystrokes run multiple or single tests at our whim, requiring barely a thought from us. This certainly comes in handy if we adhere to test-driven-development's rhythm of alternating rapidly between writing tests and writing code. Thanks to running the tests in a vertically-oriented Vim window terminal, the feedback from the tests persists on screen when we need to fix something in our code. We also have another keystroke, ct, which closes the tests as easily as we opened them. But our configuration has added safeguards to ensure this keystroke does not accidentally close a window with code we are editing. In addition, our keystrokes, quite helpfully, don't care if we've run tests in Ruby or Elixir. Our Vim script has included some abstraction, and the mapped keystrokes work for both languages. And, if our Vim script does not know what test command to use, we get a helpful warning.
Like many other languages, PowerShell has statements for conditionally executing code in yourscripts. One of those statements is the If statement. Today we will take a deep dive into one ofthe most fundamental commands in PowerShell.
Your scripts often need to make decisions and perform different logic based on those decisions.This is what I mean by conditional execution. You have one statement or value to evaluate, thenexecute a different section of code based on that evaluation. This is exactly what the ifstatement does.
? Tip: notice that the two code blocks are indented (if and else). This is essential for Python to be able to differentiate between the code that belongs to the main program and the code that belongs to the conditional.
The concept of conditional logic in programming is not anything new. Conditional logic is a fancy term for first checking for a condition (if something happened) and then doing something as a result of that condition.
Most, if not all, languages use their own version of the conditional logic construct. Think of if/then statement. One of the conditional logic constructs available in PowerShell is the switch statement.
In this article, you will learn what the PowerShell switch statement is, understand its syntax and how it works. You will also learn from the PowerShell switch examples some of the different ways that you can use conditional logic handling in your scripts.
Nevertheless, many invariants express more complex conditions limiting the possible relationships between different objects in the system, usually related through association links. For instance, this NoRentalsBlackListed constraint forbids BlackListed people from renting cars:
There are two different approaches for specifying an operation effect: the imperative and declarative approaches [27]. In an imperative specification, the designer explicitly defines the set of structural events (inserts/updates/deletes) to be applied when executing the operation. Instead, in a declarative specification, a contract for each operation must be provided. The contract consists of a set of pre- and postconditions. A precondition defines a set of conditions on the operation input and the system state that must hold when the operation is issued while postconditions state the set of conditions that must be satisfied by the system state at the end of the operation. OCL is usually the language of choice to express pre- and postconditions for operation contracts at the modeling level.