curr: Partially and fully apply arguments to functions.
In crowding/vadr: Macros, metaprogramming, and pleasant programming idioms.

Description Usage Arguments Details Value Note Author(s)

These operators help in passing arbitrary lists of arguments to functions, with a more convenient interface than do.call. The partial application operator allows saving some arguments with a reference to a function so the resulting function can be passed elsewhere.

f %()% arglist

f %<<% x

f %<<<% x

## S3 method for class '...'
f %<<<% x

curr(f, ...)

curl(f, ...)

x %__% y

`f`	a function, to be called, or to to have arguments attached to.
`arglist`	A ... object (see `dots`.)
`x`	a vector, optionally with names, or an object of class `...` as produced by `dots`.
`...`	Other arguments. to be captured without evaluating.
`y`	a ... object as constructed by `dots`.

These objects have methods for objects of class ... produced by dots, so that you may partially apply argument lists without arguments as yet unevaluated.

For %()%, the result of calling the function with the arguments provided. When x is a ... object, its contents are passed inithout evaluating. When x is another type of sequence its elements are put in the value slots of already-evaluated promises. This is slightly different behavior from do.call(f, as.list(x), quote=TRUE), which passes unevaluated promises with expressions wrapped in link{quote}. This makes a difference if f performs nonstandard evaluation.
For %<<% and %<<<%, a new function with the arguments partially applied. For f %<<<% arglist, the arguments will be placed in the argument list before any further arguments; for f %<<% arglist the arguments will be placed afterwards.
curr and curl are standalone functions that partially apply arguments to functions; curr(f, a=1, b=2) is equivalent to f %<<% dots(a=1, b=2), and curl is the "left curry" corresponding to %>>%.
For %__%, the two operands concatenated together. The result will be a list, or a dots object if any of the operands are dots objects.