Install an expression as a function

Source: R/utils.R

Installs an expression in the given environment as a function, and registers debug hooks so that breakpoints may be set in the function. Note: as of Shiny 1.6.0, it is recommended to use quoToFunction() instead.

installExprFunction(
  expr,
  name,
  eval.env = parent.frame(2),
  quoted = FALSE,
  assign.env = parent.frame(1),
  label = deparse(sys.call(-1)[[1]]),
  wrappedWithLabel = TRUE,
  ..stacktraceon = FALSE
)

Arguments

expr

A quoted or unquoted expression
name

The name the function should be given
eval.env

The desired environment for the function. Defaults to the calling environment two steps back.
quoted

Is the expression quoted?
assign.env

The environment in which the function should be assigned.
label

A label for the object to be shown in the debugger. Defaults to the name of the calling function.
wrappedWithLabel, ..stacktraceon

Advanced use only. For stack manipulation purposes; see stacktrace().

Details

This function can replace exprToFunction as follows: we may use func <- exprToFunction(expr) if we do not want the debug hooks, or installExprFunction(expr, "func") if we do. Both approaches create a function named func in the current environment.

See also

Wraps exprToFunction(); see that method's documentation for more documentation and examples.