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Changes between Version 1 and Version 2 of NilableTypes

NilableTypes

v1	v2
40	40	}}}
41	41
42		== nil and not nil detection ~~and coalesce~~ ==
	42	== nil and not nil detection ==
43	43
44	44	You can explicitly test for nil or not nil values using normal conditionals ( true is non-nil)
…	…
54	54	}}}
55	55
56		Nil test and assign or non nil test and process can be done using 'nil coalescing'[[BR]]
	56	== nil and non-nil coalesce ==
	57	Shortcuts for Nil test and assign (coalesce) or non nil test and process [[BR]]
57	58
58		'''?''' coalesce if nil.[[BR]]
	59	'''a ? b''' coalesce to b if (a) nil.[[BR]]
	60	The expression evaluates to a unless that value is nil, in which case, it evaluates to b.[[BR]]
	61	Neither expression will be evaluated more than once and if the first expression is non-nil then b will not be evaluated at all.[[BR]]
	62	( Also the direct augmented assignment version '''a ?= b''' a gets b if a is nil )
59	63
60		'''~~! ''' execute if~~ not nil.
	64	'''a ! b ''' evaluate b if a not nil.
61	65	{{{
62	66	stuff as String? = nil
…	…
64	68
65	69	stuff = stuff ? defaultStuff # coalesce nil
	70	# OR stuff ?= defaultStuff
66	71	# equivalent to stuff = if (not stuff, defaultStuff, stuff)
67	72	# or