xHarbour Reference Documentation > Function Reference

HB_IsNIL()

Tests if the value returned by an expression is NIL.

Syntax

HB_IsNIL( <expression> ) --> lIsNIL

Arguments

<expression>

This is an expression of any data type.

Return

The function returns .T. (true) if the value returned by <expression> is NIL, otherwise .F. (false) is returned.

Description

Function HB_IsNIL() is used to test if a variable contains the value NIL or if the result of an expression is of undefined data type. The function can be used as a replacement for the expression: Valtype(<expression>)=="U".

Info

See also:	HB_IsArray(), HB_IsBlock(), HB_IsByRef(), HB_IsDate(), HB_IsHash(), HB_IsLogical(), HB_IsMemo(), HB_IsNull(), HB_IsNumeric(), HB_IsObject(), HB_IsPointer(), HB_IsString(), Type(), Valtype()
Category:	Debug functions , Logical functions , xHarbour extensions
Source:	rtl\valtype.c
LIB:	xhb.lib
DLL:	xhbdll.dll