keep entries from list of flags by name, name/value pair, or index

keep entries from list of flags by name, name/value pair, or index

cmd_list_keep(flags, keep)

Arguments

flags	named list output of cmd_list_interp
keep	vector of flag entries to keep. Pass a character vector to keep flags by name. Pass a named vector to keep flags by name/value pairs. Pass a numeric vector to keep by position.

Value

flags list with values not in keep removed

Examples

exFlags <- list("flag1" = 2, "flag2" = "someText")
cmd_list_keep(exFlags, "flag1")
#> $flag1
#> [1] 2
#> 
# will keep flag2 because its name and value match 'keep' vector
cmd_list_keep(exFlags, c("flag2" = "someText"))
#> $flag2
#> [1] "someText"
#> 
# Will keep "flag1" by position index
cmd_list_keep(exFlags, 1)
#> $flag1
#> [1] 2
#> 

# won't keep flag2 because its value isn't 'someText'
exFlags2 <- list("flag1" = 2, "flag2" = "otherText")
cmd_list_keep(exFlags, c("flag2" = "someText"))
#> $flag2
#> [1] "someText"
#>