Lingo Dictionary > O-R > objectP()

 

objectP()

Syntax

objectP(expression)

Description

Function; indicates whether the expression specified by expression is an object produced by a parent script, Xtra, or window (TRUE) or not (FALSE).

The P in objectP stands for predicate.

It is good practice to use objectP to determine which items are already in use when you create objects by parent scripts or Xtra instances.

To see an example of objectP() used in a completed movie, see the Read and Write Text movie in the Learning\Lingo Examples folder inside the Director application folder.

Example

This statement checks whether the global variable gDataBase has an object assigned to it and, if not, assigns one. This check is commonly used when you perform initializations at the beginning of a movie or section that you don't want to repeat.

if objectP(gDataBase) then
	nothing
else
	gDataBase = script("Database Controller").new()
end if

See also

floatP(), ilk(), integerP(), stringP(), symbolP()