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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/functional_section_fun.R
\name{set_default}
\alias{set_default}
\title{Set default values in a functions arguments}
\usage{
set_default(fun, nms, vls = NULL)
}
\arguments{
\item{fun}{A function whose arguments will get new default values.}
\item{nms}{Character vector of argument names, or something coercible to that
(e.g. a call to \code{v()}).}
\item{vls}{Optional vector or list of values to use as defaults.
If \code{nms} is a named list, \code{vls} can be \code{NULL}.}
}
\value{
A new function with updated default values in its formals.
}
\description{
\code{set_default()} takes a function and returns a new version with
updated default values for specified arguments.
}
\details{
This is useful when you want to programmatically create specialized
versions of a function with certain arguments preset to default
values.
\itemize{
\item The specified arguments will be moved to the end of the formal argument list in the returned function.
\item You can supply arguments as a named list or as separate names and values.
}
}
\examples{
## Simple example
f1 <- function(x, y, z) { x + y + z }
## Add defaults for x and y
set_default(f1, list(x = 1, y = 2))
# function (z, x = 1, y = 2) { x + y + z }
## Same using separate vectors of names and values
set_default(f1, c("x", "y"), c(1, 2))
## Works with v() style if supported
# set_default(f1, v(x, y), c(1, 2))
## Another example with more arguments
f2 <- function(a, b, c, d) { a + b + c + d }
set_default(f2, list(b = 10, d = 5))
}
\concept{functional}
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