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

Section: 26.2.7 [unord.req], 26.5 [unord] Status: NAD Submitter: Matt Austern Opened: 2009-08-10 Last modified: 2016-02-10

Priority: Not Prioritized

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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)
ExpressionReturn typeAssertion/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 26.5.4 [unord.map], 26.5.5 [unord.multimap], 26.5.6 [unord.set], and 26.5.7 [unord.multiset].

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