Feature Wish List

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• More Enumerable methods for lists, arrays and maps (like map, pluck, invoke, ...)

• Make logical operators (||, &&...) return the value instead of the boolean equivalent
  eg.

  Code Block
  def x = '' || 'test' assert x == 'test' def x = null || 15 assert x == 15

• Make map creation more versatile.  Add constructors that allow creation of a map from 2 collections "HashMap(keys, values)" or a list of entries "HashMap(itemlist)".
• Make a list and create an auto mapping:

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1. Enable operator overloading for logical AND, logical OR, logical NOT. For logical AND and logical OR, the deferred evaluation of the right operand can be maintained by passing a Closure to the method.  The signatures might be something like this:

   Code Block
   Boolean land(Closure)   Boolean lor(Closure) Boolean lnot()

2. Enable assignment operator overloading.  This is needed to allow a semantic like

   Code Block
   MyBooleanClass bool = true

   Note that overriding the assignment operator makes it significantly easier to replace numeric types too since one can handle cases like

   Code Block
   MyNumericClass num = 10

   which is not possible today.

3. Today due to "Groovy Truth" processing, any non-null object reference (that is not a Boolean) will evaluate to true.  To enable user-defined Boolean type data, Groovy Truth would need to be modified to optionally "unbox" a non-null object reference into a Boolean value if it has a booleanValue() method.  This would allow one to do something like this

   Code Block
   MyBooleanType bool = something(); if bool || somethingElse() { ... }

   In such a case, the bool instance can be either false or true and can be directly used for control flow and other operations that normally expect a Boolean.
   With these changes, user-defined boolean replacement classes would get first-class support in the language.

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