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Studio User Guide

Last updated Oct 23, 2025

ST-NMG-002 - Arguments Naming Convention

Rule ID: ST-NMG-002

Scope: Workflow

Description

This rule analyzes all arguments in the project and determines whether they follow the specific convention.

Arguments in the project should follow a specific naming convention to make it easier to understand the project and maintain it. The argument name should be meaningful and include an indication of its type:

  • in – the argument can only be used within the given project.
  • out – the argument can be used to pass data outside of a given project.
  • io – the argument can be used both within and outside of a given project.

Recommendation

Make sure all arguments follow the naming convention. The default Regex expression for this rule is:

  • InRegex: ^in_(dt_)?([A-Z]|[a-z])+([0-9])*$
  • OutRegex: ^out_(dt_)?([A-Z]|[a-z])+([0-9])*$
  • InOutRegex: ^io_(dt_)?([A-Z]|[a-z])+([0-9])*$.

According to the above regex expression, the argument matches the expression if it starts with a prefix, followed by a lower or upper case letter, and a number.

For example, if the argument name in the workflow is in_HelloWorld then it is validated by the rule. Other examples of argument names that follow this regex rule are: out_HelloWorld and io_Helloworld.

Modifying the Rule

In the Project Settings window, select the Workflow Analyzer tab. Find and select the rule, as in the image below:



In the Regex section, add or remove characters from the search pattern. For example, if we remove the [A-Z] part of the expression for In arguments, the search pattern becomes ^in_(dt_)?([a-z])+([0-9])*$. Now the rule checks if In arguments start with a lower case letter after the prefix.
If we add [a-z]|[A-Z]), then the rule becomes ^in_(dt_)?([A-Z]|[a-z]|[a-z]|[A-Z])+([0-9])*$, and recognizes in_HelloWonderfulWorld as a valid In argument name.

Examples of Regex Expressions

The default regex expression for this rule can be changed to another naming convention. Check the list below:

Camel case

The camel case convention specifies that each word in the middle of the argument name begins with a capital letter, with no intervening spaces or punctuation.

Example of Regex expression: ^in_(dt_)?([A-Z]|[a-z]|[0-9])+([A-Z]|[a-z]|[0-9]).
Valid argument names: in_Hello1World2, in_helloWorld, in_Hello1World.
Pascal case

The Pascal case naming convention specifies that the argument name must contain concatenated capitalized words.

Example of Regex expression: ^in_(dt_)?([A-Z]|[0-9])+([A-Z]|[a-z]|[0-9]).
Valid names: in_Hello1World2, in_HelloWorld, in_Hello1World.
Kebab case

The Kebab case naming convention is similar to snake case, except that it replaces spaces with hyphens rather than underscores.

Example of Regex expression: ^in_(dt_)?([a-z]|[A-Z]|[0-9])+‐([a-z]|[A-Z]|[0-9])
Valid names: in_Hello1‐World2, in_Hello‐World.

Reset to Default Values

The default values for ST-NMG-002 Regex are:

  • InRegex: ^in_(dt_)?([A-Z]|[a-z])+([0-9])*$
  • OutRegex: ^out_(dt_)?([A-Z]|[a-z])+([0-9])*$
  • InOutRegex: ^io_(dt_)?([A-Z]|[a-z])+([0-9])*$.

To reset these values to default right-click a rule in the Project Settings window, and then click Reset to default.



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