If the first parameter Argis valid (i.e. the value of attribute VLD of parameter Argis TRUE), the function returns the parameter Arg. If the first parameter Argis invalid, the function returns the second parameter Replacement.
Declaration
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language
esl
theme
Confluence
UNIVAL %IsNull(
UNIVAL in Arg
UNIVAL in Replacement
)
Parameters
Arg
Compared value.
Replacement
Replacement value if Argis invalid.
Example
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language
esl
theme
RDark
INT _i, _j, _k
_i := %IsNull ( Sec, Min) ; returns value of Sec, as it is always valid
_i := %SetInvalid(_i) ; invalidate the value
_j := 999
_k := %IsNull ( _i, _j) ; returns value 999, as the value of _i is invalid