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PCOUNT()
Determine the position of the last actual parameter passed
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Syntax
PCOUNT() --> nLastArgumentPos
Returns
PCOUNT() returns, as an integer numeric value, the position of the last
argument passed. If no arguments are passed, PCOUNT() returns zero.
Description
PCOUNT() reports the position of the last argument in the list of
arguments passed when a procedure or user-defined function is invoked.
This information is useful when determining whether arguments were left
off the end of the argument list. Arguments skipped in the middle of
the list are still included in the value returned.
To determine if a parameter did not receive a value, test it for NIL.
Skipped parameters are uninitialized and, therefore, return NIL when
accessed. Another method is to test parameters with the VALTYPE()
function. This can establish whether the argument was passed and
enforce the correct type at the same time. If a parameter was not
supplied, a default value can be assigned.
For more information on passing parameters, refer to the "Basic
Concepts" chapter in the Programming and Utilities Guide.
Examples
. This example is a user-defined function that opens a database
file and uses PCOUNT() to determine whether the calling procedure
passed the name of the database file to be opened. If the name was
not passed, OpenFile() asks for the name:
FUNCTION OpenFile( cFile )
IF PCOUNT() = 0
ACCEPT "File to use: " TO cFile
ENDIF
USE (cFile)
RETURN (NETERR())
Files Library is CLIPPER.LIB.
See Also: DO* FUNCTION PARAMETERS PROCEDURE VALTYPE()
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