The options environment stores primarily, the default values for options. In addition, it stores metadata pertaining to each option in the form of attributes.
options_initialized(env, inherits = FALSE)init_options_env(env = parent.frame())
as_options_list(x, ...)
# S3 method for list
as_options_list(x, ...)
# S3 method for options_env
as_options_list(x, ...)
get_option_default_value(x, env = parent.frame())
get_options_spec(env = parent.frame())
get_option_spec(
name,
env = parent.frame(),
inherits = FALSE,
on_missing = warning
)
set_option_spec(name, details, env = parent.frame())
An environment in which to search for an options environment
Whether to search upward through parent environments
Additional arguments unused
options_initialized()
: Test whether options is initialized in environment
init_options_env()
: Initialize an options object
as_options_list()
: Convert into an options list
get_option_default_value()
: Get the option's default value
get_options_spec()
: Get all options specifications as named list
get_option_spec()
: Get single option specification
set_option_spec()
: Set single option specification
spec
: A named list of option specifications
option_name_fn
: A function used to derive default option names for
newly defined options. See set_option_name_fn()
.
envvar_name_fn
: A function used to derive default environment variable
names for newly defined options. See set_envvar_name_fn()
.