var - any variable name, local variable name, or global variable name (see
About naming fields for guidelines on naming variables).
calculation - any calculation expression, field, or constant.
The $ symbol references a local variable and two $$ symbols reference a global variable. An optional repetition number appears in square brackets [ ] immediately after the variable name. For example:
The Let function sets the variables from left to right. You can use previously defined variables (for example, variables that you defined with the Set Variable script step) to define new variable values, and you can nest one
Let function within another. If you use a previously defined variable within a nested
Let function, the variable has scope only within the nested function (as if you had defined a completely unique variable). See the City example shown below.
Once defined, local and global variables can be referenced in any calculation within their scope. The scope of global variables is limited to the current file. The scope of local variables is the current script. Local variables defined in a calculation are scoped to the file but are only available when scripts are not running. A local and global variable (or even two local variables in different scripts) can have the same name but they are treated as different variables and store different values.
The following example shows how to pass named parameters using the Evaluate,
Let, and
Get(ScriptParameter) functions, allowing access only to variable
“a” (the example returns
6):
The following example shows how to pass named parameters, allowing access to both variable “a” and variable
“b”. The simplified first parameter makes the second parameter more complex (the example returns
6, 12):