FilterArgs4Func: Keep Wanted Arguments According to A Function from Dots

In SigBridgeRUtils: Some Utilities & Base Supports for 'SigBridgeR'

Keep Wanted Arguments According to A Function from Dots

Description

FilterArgs4Func filters a list of arguments to include only those that match the formal arguments of a specified function, with optional support for preserving additional arguments via the keep parameter. This is useful for preparing argument lists for function calls, especially when dealing with functions that have many optional parameters or when passing arguments through multiple function layers.

Usage

FilterArgs4Func(args_list, fun, keep = NULL)

Arguments

args_list	A named list of arguments to filter
fun	The target function whose formal arguments will be used for filtering
keep	Character vector of argument names to preserve regardless of whether they appear in fun's formal parameters. Default is NULL. Useful for retaining arguments needed by downstream functions or wrappers that consume ....

Details

This function is particularly useful in scenarios where you have a large list of parameters and want to pass only the relevant ones to a specific function while preserving certain arguments for downstream processing (e.g., arguments consumed by nested ... parameters).

The keep parameter enables flexible argument forwarding patterns common in wrapper functions and pipeline designs.

Value

A filtered list containing:

• Arguments from args_list that match formal parameters of fun (excluding the "..." parameter)

• Additional arguments specified in keep (if not NULL)

See Also

formals() for accessing function formal arguments, do.call() for executing functions with argument lists, names() for working with list names

Examples

## Not run: 
# Example function with specific parameters
example_function <- function(a, b, c = 10, d = 20) {
  return(a + b + c + d)
}

# Create a list with both relevant and irrelevant arguments
all_args <- list(
  a = 1,
  b = 2,
  c = 3,
  e = 4,  # Not in function formals
  f = 5   # Not in function formals
)

# Basic usage: filter to only include arguments matching function parameters
filtered_args <- FilterArgs4Func(all_args, example_function)
print(filtered_args)
#> $a
#> [1] 1
#>
#> $b
#> [1] 2
#>
#> $c
#> [1] 3

# Advanced usage: preserve additional arguments for downstream processing
filtered_with_keep <- FilterArgs4Func(all_args, example_function, keep = c("e", "f"))
print(filtered_with_keep)
#> $a
#> [1] 1
#>
#> $b
#> [1] 2
#>
#> $c
#> [1] 3
#>
#> $e
#> [1] 4
#>
#> $f
#> [1] 5

# Execute with filtered arguments
result <- do.call(example_function, filtered_args)
print(result)
#> [1] 16

## End(Not run)

SigBridgeRUtils documentation built on Sept. 29, 2026, 5:09 p.m.