Compiling the expression
The code is recompiled whenever EvaluateExpression is called.
To avoid the compilation step, you can use
Compile and
Execute to build the code of a procedure, compile it once and run it several times. In this case, you will lose the ability to directly use local variables of the current process which will need to be replaced by parameters in the procedure.
Using a procedure of external component
The code is recompiled whenever EvaluateExpression is called.
The call to a procedure of external component must name this procedure with its full name.
EvaluateExpression("MyComponent.MySet.MyProcedure()"))
If the source code used for the dynamic compilation contains names of files, items, controls, windows, reports, queries, ... these names must necessarily be enclosed in quotes.
For example, you must use: HReadFirst("Customer", "Name") instead of HReadFirst(Customer, Name)
The
constants cannot be used in the dynamic code (defined by the
CONSTANT keyword).
When using constants in a code, all the occurrences of the constants are replaced by their value during the compilation in the editor but the correspondence between the name of constants and their value is not "embedded" in the application. Therefore, the dynamic compilation cannot use the constants.
Let's see two alternatives:
1 - Use variables instead of constants:
or
2 - In the string containing the code that must be compiled dynamically, replace the name of the constant by its value:
sCode is string
// In the string containing the code that will be compiled dynamically
// instead of leaving the name of the constant:
sCode=[
Info(CST_Name)
]
// Replace the name of the constant by its value
sCode = Replace(sCode, "CST_Name", CST_Name, WholeWord + IgnoreCase)
// The code can be compiled now
IF Compile("DynProc", sCode) <> "" THEN
Error("Error while compiling the dynamic procedure: ", ...
ErrorInfo())
ELSE
// Then it can be run
WHEN EXCEPTION IN
ExecuteProcess("DynProc", trtProcedure)
DO
Error("Error while running the dynamic procedure: ", ...
ExceptionInfo())
END
END