lang_args {rlang} | R Documentation |
Extract arguments from a call
lang_args(lang) lang_args_names(lang)
lang |
Can be a call (language object), a formula quoting a call in the right-hand side, or a frame object from which to extract the call expression. |
A named list of arguments.
lang_tail()
, fn_fmls()
and fn_fmls_names()
call <- quote(f(a, b)) # Subsetting a call returns the arguments converted to a language # object: call[-1] # See also lang_tail() which returns the arguments without # conversion as the original pairlist: str(lang_tail(call)) # On the other hand, lang_args() returns a regular list that is # often easier to work with: str(lang_args(call)) # When the arguments are unnamed, a vector of empty strings is # supplied (rather than NULL): lang_args_names(call)