Chapter 5 Customizing Generation with GTL

Operators

The following operators are supported in GTL:

Symbol Description
* Dereferencing operator - The syntax [*]+local-value [(parameter-list)] returns the object member defined by the evaluation of [*]+ local-value. If the given object member happens to be a template, a parameter list may be specified. Applying the star operator corresponds to a double evaluation (the * operator acts as a dereferencing operator).

If a local variable is defined as: .set_value(C, Code) , then %C% will return "Code" and %*C% will return the result of the evaluation of %Code%. In other words, %*C% can be thought of as %(%C%)% (the latter syntax being invalid).
! Power evaluation operator - Evaluates the results of the evaluation of the variable as a template. For example, you define a comment containing a variable like %Code%. When you use the ! operator in %!Comment% , the actual value of %Code% is substituted for the variable block. Without the ! operator, the variable remains unevaluated.

The ! operator may be applied any number of times. For example: 

%!!template%


This outputs the results of the evaluation of the evaluation of the evaluation of template 'template'
? The ? operator is used to test the existence of a template, a local variable, a volatile or an extended attribute. It returns "true" if the variable exists, "false" otherwise.

For example, if custname is defined whereas custid is not, then the template: 

.set_value(foo, tt)
%custname?%
%custid?%


outputs: 

true
false
+ The + operator is used to test if an object property is visible in the interface.

For example, you could test if the Type box is displayed in the General tab of a database property sheet in an ILM, and thus that the Replication Server or MobiLink XEM is attached to the model.

The %Database.Type+% template will output false if no XEM is attached to the model.

 

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