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21		=== fieldLabel declaration (data dictionary) ===
	21	=== Option One: fieldLabel declaration (data dictionary) ===
22	22
23	23	There is to be a new declaration type, examples:
…	…
39	39	That is: the `r{ ... }` constraint is added by the desugarer (and will be further desugarred to a `Has` constraint).
40	40
	41	=== Option Two: explicit record constraint ===
	42
41	43	[Or perhaps the new `fieldLabel` declaration isn't needed. See a ''__very__ speculative'' discussion at [wiki:Records/DeclaredOverloadedRecordFields/COmpareSORF#TheStringtypeparametertoHasandScopecontrol Wilder aftererthought] ]
	44
	45	Declaring:
	46	{{{
	47	customer_id :: r{ customer_id :: Int } => r -> Int -- explicit record constraint
	48	-- field name same as the function name
	49	}}}
	50	Desugars to the same as for `fieldLabel`. That is the proxy type and the binding:
	51	{{{
	52	data Proxy_customer_id
	53	customer_id r = get r (undefined :: Proxy_customer_id)
	54	}}}
	55	'''Note:''' the desugarring only applies where the field and function are the same name (and record type argument and result type). Otherwise this syntax is declaring a regular function with a record constraint (could be a 'virtual' field).
	56
42	57
43	58	=== Syntactic sugar for `Has` ===