sym creates a symbol from a string and
syms creates a list of symbols from a
character vector.
enquo and
enquos delay the execution of one or
several function arguments. enquo() returns a single quoted
expression, which is like a blueprint for the delayed computation.
enquos() returns a list of such quoted expressions.
expr quotes a new expression locally. It
is mostly useful to build new expressions around arguments
captured with enquo() or enquos():
expr(mean(!!enquo(arg), na.rm = TRUE)).
as_name transforms a quoted variable name
into a string. Supplying something else than a quoted variable
name is an error.
That's unlike as_label which also returns
a single string but supports any kind of R object as input,
including quoted function calls and vectors. Its purpose is to
summarise that object into a single label. That label is often
suitable as a default name.
If you don't know what a quoted expression contains (for instance
expressions captured with enquo() could be a variable
name, a call to a function, or an unquoted constant), then use
as_label(). If you know you have quoted a simple variable
name, or would like to enforce this, use as_name().
To learn more about tidy eval and how to use these tools, visit the Metaprogramming section of Advanced R.
Nothing returned.
This is to document important functions from rlang that are used internal to this R package.