[GROOVY-4144] Closures should have rcurry and ncurry as well as curry

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7.1
• Fix Version/s: 1.7.2, 1.8-beta-1
• Assignee: Paul King
• Reporter: Paul King
• Created: 03/Apr/10 02:35
• Updated: 07/Apr/15 19:12
• Resolved: 03/Apr/10 17:35

Description

Sometimes you don't want to curry from the left hand side. You can always fake it by rewriting a reversed method or Closure manually but most functional languages support currying from the right or an arbitrary index.

An rcurry method allows examples like this:

def divide = { a, b -> a / b }
def halver = divide.rcurry(2)
assert halver(8) == 4

An ncurry method would allow, as an example, to curry the middle parameter of a three argument method, e.g.:

// curry middle param of this utility method:
// Collections#binarySearch(List list, Object key, Comparator c)
def catSearcher = Collections.&binarySearch.ncurry(1, "cat")
def result = catSearcher(myList, myComparator)