Low-level pointer details

Source: R/utils.R

  • adbc_xptr_move() allocates a fresh R object and moves all values pointed to by x into it. The original R object is invalidated by zeroing its content. This is useful when returning from a function where lifecycle helpers were used to manage the original object.

  • adbc_xptr_is_valid() provides a means by which to test for an invalidated pointer.

adbc_xptr_move(x, check_child_count = TRUE)

adbc_xptr_is_valid(x)

Arguments

x

An 'adbc_database', 'adbc_connection', 'adbc_statement', or 'nanoarrow_array_stream'

check_child_count

Ensures that x has a zero child count before performing the move. This should almost always be TRUE.

Value

  • adbc_xptr_move(): A freshly-allocated R object identical to x

  • adbc_xptr_is_valid(): Returns FALSE if the ADBC object pointed to by x has been invalidated.

Examples

db <- adbc_database_init(adbc_driver_void())
adbc_xptr_is_valid(db)
#> [1] TRUE
db_new <- adbc_xptr_move(db)
adbc_xptr_is_valid(db)
#> [1] FALSE
adbc_xptr_is_valid(db_new)
#> [1] TRUE