Value Source Expressions

The most common way to edit a value source is with the inline value source editor, which allows creation of value sources using simple expressions.

Value Source Expressions provide a textual representation for value sources that is typically quicker to edit than using the Advanced Value Source Editor. Here are some examples of common expressions:

Source type Type Id Examples
Text string string "my text string", "\"string with quotes \""
Integer integer 1234
Boolean boolean true, false
Add or concatenate add "this concatenated " + " with this", 123 + 456
Local variable variable $"variable_name"
Project resource resource #"resource_id"
Equality comparison equals 123 == 456
Selenium element locator element-id <id:"element_id">
Method call (various) method_name(param1, param2…)

Rather than providing a comprehensive list (that would soon be out of date), I suggest looking through the examples and edit those of interest to see the expressions that are produced for them. Also, you can build a complex value source using the Advanced Value Source Editor and then inspect the expression created for it.

Parenthesis are supported for specifying operator precedence

Note: not all value source configurations can be converted to, or parsed from, an expression string.

Default Value Source Editor

When value sources are edited inline or within the step editor, they are editable using value source expressions (when the step and value sources allow it). But they can also be edited more directly, with the more link beside the inline editor.

As described in the Muse Framework docs, value sources are composed of other sub-sources and/or a raw value (quoted string, integer, true/false or null). This editor allows you to choose the value source type and set the sub-sources.

In this example, the while step has a single value source, which is the condition to evaluate. In this case, the condition is

$"counter" < 4

In the advanced editor, you can see that it is a Less Than value source, which contains two named sub-sources, left and right. If you further expanded the left source, you would see that it is a variable value source that contains a single sub-source (type string), which contains the name of the variable to be used.


Note that value sources can have sub-sources that have sub-sources and so on. They can be nested arbitrarily deep.

Expert Value Source Editor

Use the expert mode link to switch to Expert mode. The expert editor allows configuration of parameters in a very general way. While it enforces a configuration that is coherent with the underlying data structures, it does not enforce a configuration that is valid for the specific value source. This may cause unexpected behavior - use at your own risk. Refer to the value source documentation for the valid sub-sources. The Getting Started Guide demonstrates the command-line documentation tools.