calledby(
DATABASE
,
PROCEDURE
)
The calledby( function returns true if this function is in code called by the specified database, the specified procedure, or both.
Parameters
This function has two parameters:
database – database to check for. If this parameter is empty (""
) or ommitted, then any database will match.
procedure – procedure to check for. If this parameter is empty (""
), then any procedure will match (allowing you to check for any procedure in a specific dataabase).
Description
This function checks to see if the current code is running as a subroutine of a specific datbase and/or procedure. For example, suppose you want to check if the current code is initializing a database.
if calledby(".Initialize")
... do something special only when initializing
endif
In the example above, the calledby( function will return true in any subroutine that has been called by .Initialize
. (It will also return true for code in the .Initialize
procedure itself.
If you need to be more specific, the calledby( function can narrow the check to a procedure in a specific database. In this example, the extra code will only run if it has been called by the .Initialize
procedure in this database. It won’t be called if some other database is being initialized.
if calledby(info("proceduredatabase"),".Initialize")
... do something special only when initializing THIS database
endif
If the database is specified but the procedure is left blank, the function will return true if it has been called by any procedure in the specified database.
if calledby("Zork","")
returnerror "We don't like zork"
endif
Probably a more common use for this would be to check if the code is being called from another database. Perhaps for security reasons you don’t want to allow that.
if calledby(info("proceduredatabase"),"")=false()
returnerror "Can't call this from other databases"
endif
See Also
- call -- allows a procedure to call a separate procedure within the current database as a subroutine.
- call( -- allows a procedure to be called as a subroutine within a formula and return a result.
- callerslocalvariablevalue( -- allows a subroutine to access a local variable in the procedure that called it.
- callingdatabase( -- returns the name of the database that called this procedure as a subroutine, if any.
- callingprocedure( -- returns the name of the procedure that called this procedure as a subroutine, if any.
- callwithin -- allows a procedure to call a mini-procedure within a separate procedure within the current database as a subroutine.
- callwithin( -- allows a "mini-procedure" to be called as a subroutine within a formula and return a result.
- callwithindatabase( -- returns true if the current procedure was called by another procedure in the same database, false if it was called by a procedure in another database.
- case -- allows multiple decisions to be chained together (also see the elseif statement).
- catch -- works with try and endcatch to trap errors in a sequence of statements.
- Custom Database Initialization -- using an .Initialize procedure to automatically run custom code when a database opens.
- debug -- stops the current program, allowing you to examine variables or single step.
- defaultcase -- works together with the case statement to specify statements that will be executed if none of the *case* statements are true.
- disableabort -- prevents loops from being stopped early by pressing SHIFT-COMMAND-ESCAPE or by exceeding the maximum allowed loop time.
- else -- works together with the if statement to specify statements that will be executed for both the *true* and *false* cases.
- elseif -- allows multiple if decisions to be chained together.
- enableabort -- allows the SHIFT-COMMAND-ESCAPE key sequence to stop an endless loop.
- endcase -- marks the end of statements controlled by a previoius case statement.
- endcatch -- works with try and catch to trap errors in a sequence of statements.
- endif -- marks the end of statements controlled by a previoius if statement.
- endloop -- is used at the end of a loop.
- Error Handling -- Techniques for trapping runtime errors instead of letting them abort the program.
- Error Wizard -- Advanced dialog for displaying program errors.
- execute -- allows a procedure to call a sequence of statements within the current procedure as a "mini-subroutine".
- execute( -- allows a formula to execute a sequence of statements and return a result.
- executeasap -- executes the specified code at the first possible opportunity, non-atomically.
- executecatcherrors -- is the same as the execute statement, except for the fact that if an error occurs while running, it can be trapped by an if error statement immediately following the executecatcherrors statement.
- executelocal -- is the same as the execute statement, but it shares local variables with the procedure that called it.
- farcall -- allows a procedure to call a separate procedure within a different database as a subroutine.
- farcallwithin -- allows a procedure to call a mini-procedure within a separate procedure in a different database as a subroutine.
- for -- is used at the beginning of a loop that loops a fixed number of times.
- goto -- allows a procedure to arbitrarily jump from one spot to another
within the procedure.
- if -- decides what code to execute next.
- info("callerslocalvariables") -- returns a list of local variables defined in the procedure that called the current procedure.
- info("error") -- returns the most recent error message.
- info("labels") -- lists the labels in the current procedure.
- info("procedurestack") -- returns the contents of Panorama's procedure call stack.
- loop -- is used at the beginning of a loop.
- looparray -- is used at the beginning of a loop that loops over the elements of an array.
- loopdataarray -- is used at the beginning of a loop that loops over the elements of a data array.
- loopindex -- allows a procedure to determine how many times a loop has been repeated.
- loopwhile -- is used at the beginning of a loop.
- noimplicitassignment -- does nothing, and is only retained for compatibility with earlier versions.
- nop -- does nothing (**n**o **op**eration).
- onerror -- can be used to catch all errors that are not trapped by if error or try statements.
- onfailedresume -- is used to setup a semi-graceful recovery if a resume statement fails because there was no pause statement.
- parameter( -- is used to transfer data between a main procedure and a subroutine.
- pause -- temporarily pauses a procedure.
- Preventing Endless Loops -- setting up a timeout limit to prevent endless loops.
- quit -- quits Panorama.
- repeatloopif -- decides whether to continue with a loop or to start over again from the top.
- resume -- resumes a procedure that has been temporarily halted with the pause statement.
- resumeaftertask -- resumes after a waitfortask statement.
- return -- ends a subroutine.
- returnerror -- passes an error back to the current subroutines calling procedure.
- setcallerslocal -- allows a subroutine to modify a local variable in the procedure that called it.
- seterror -- changes the error message returned by info("error").
- setparameter -- is used to transfer data from a subroutine back to the main
procedure that called it.
- setwaitinglocal -- assigns a value to a local variable in the parent procedure of an asynchronous task, allowing the asynchronouse code to pass a value back to the code that spawned it.
- shortcall -- allows a procedure to call a sequence of statements within the current procedure as a "mini-subroutine".
- stop -- stops all running procedures immediately.
- stoploopif -- decides whether to continue with a loop or to exit the loop immediately.
- throwerror -- causes an immediate error.
- try -- works with catch and endcatch to trap errors in a sequence of statements.
- until -- is used at the end of a loop, and can control how many times the loop is executed.
- usecallerslocalvariables -- temporarily swaps out a subroutine's current local variables with the local variables of the procedure that called this subroutine. The statement can be used only in a subroutine, not in a calling procedure.
- usefunctioncallerslocalvariables -- temporarily swaps out a procedures current local variables with the local variables of the procedure that called this the call(, callwithin( or execute( function.
- usemylocalvariables -- reverses the action of the UseCallersLocalVariables statement, switching back to the current procedure's normal local variables.
- waitfortask -- temporarily pauses a procedure until the specified task is complete.
- while -- is used at the end of a loop, and can control how many times the loop is executed.
History
10.2 | New | New in this version. |