1190. Setting the maximum load factor should return the previous value

Section: 23.2.8 [unord.req], 23.5 [unord] Status: NAD Submitter: Matt Austern Opened: 2009-08-10 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

The unordered associative container requirements table specifies that a.set_max_load_factor(z) has return type void. However, there is a useful piece of information to return: the previous value. Users who don't need it can always ignore it.

[ 2010 Rapperswil: ]

The benefit seems minor, while breaking with the getter/setter idiom these overloads support. Move to Tentatively NAD.

[ Moved to NAD at 2010-11 Batavia ]

Proposed resolution:

In the unordered associative container requirements table, change:

Table 87 — Unordered associative container requirements (in addition to container)

Expression	Return type	Assertion/note pre-/post-condition	Complexity
a.max_load_factor(z)	void float	Pre: z shall be positive. Changes the container's maximum load load factor, using z as a hint. Returns: the previous value of a.max_load_factor().	constant

Change the return type of set_max_load_factor in the class synopses in 23.5.3 [unord.map], 23.5.4 [unord.multimap], 23.5.6 [unord.set], and 23.5.7 [unord.multiset].

If issue 1188 is also accepted, make the same changes for min_load_factor.