isNilPointer | R Documentation |
This function allows the caller to determine if the external pointer does not point to a valid address in memory but instead points to 0 or NULL. This is an R equivalent to checking if the external pointer is NULL at the C level
isNilPointer(ref)
ref |
an external pointer or object that is derived from RCReference (or has a 'ref' slot that is an external pointer). |
A logical value that is TRUE
if the external pointer value is 0/NULL.
Duncan Temple Lang
p = new("externalptr") isNilPointer(p) r = new("RCReference", ref = p) isNilPointer(p)
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