Almost anywhere in the EachScape Studio that you can supply text, it is possible to also insert an expression.

An expression is a string that contains the special characters [[ ]]. These special characters indicate the start of an area where a substitution will occur in your app at the time the app is running.

In other words, only when the app is running with the evaluation of these characters occur. This means you can type junk in there, and that will result in an empty value. For example, if you type
The first record contains [[secret]] data.

Because [[secret]] isn't recognized as an known expression, the result will be “The first record contains data.”.

Expression are used extensively to:

In addition to substitution you can use functions ~ formatter to perform many operations on these values.