Quick Option-like Feature

Source: R/options.R

mkoptions is a function that returns a function that behaves like options, with an attached internal/local list of key-value pairs.

mkoptions(...)

.options(..., .DATA)

Arguments

...

list of keys or key-value pairs. For mkoptions these define inital/default key-value pairs.
.DATA

a list or an environment with an element .options.

Functions

  • .options: is a low-level function that mimics the behaviour of the base function options, given a set of key-value pairs. It is the workhorse function used in mkoptions and package-specific option sets (see setupPackageOptions)

See also

setupPackageOptions

Examples

f <- mkoptions(a=3, b=list(1,2,3))
str(f())

#> List of 2
#>  $ a: num 3
#>  $ b:List of 3
#>   ..$ : num 1
#>   ..$ : num 2
#>   ..$ : num 3
f('a')

#> $a
#> [1] 3
#> 
f('b')

#> $b
#> $b[[1]]
#> [1] 1
#> 
#> $b[[2]]
#> [1] 2
#> 
#> $b[[3]]
#> [1] 3
#> 
#> 
str(old <- f(a = 10))

#> List of 1
#>  $ a: num 3
str(f())

#> List of 2
#>  $ a: num 10
#>  $ b:List of 3
#>   ..$ : num 1
#>   ..$ : num 2
#>   ..$ : num 3
f(old)
str(f())

#> List of 2
#>  $ a: num 3
#>  $ b:List of 3
#>   ..$ : num 1
#>   ..$ : num 2
#>   ..$ : num 3