P1619 Functions for Testing Boundary Conditions on Integer Operations

[wg21bot]

P1619R0 Functions for Testing Boundary Conditions on Integer Operations (Lisa Lippincott)

[tituswinters]

This R0 should be seen by the relevant SG before going to LEWG.

[jensmaurer]

SG6 in Cologne: "Forward to LEWG? unanimous consent."

[wg21bot]

P1619R1 Functions for Testing Boundary Conditions on Integer Operations (Lisa Lippincott)

[Cpp-Lisa]

Additions in R1 were shown in SG6 in Belfast.

[tituswinters]

Discussed in Prague.

We are OK with the predicate design, even though we’re potentially discarding information.
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We want to open naming discussion for “can_remainder”.

Author: please consider “can_take_remainder”

We want “can_compare” even though we have P0586 (safe integral comparisons).
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Choose a header.
Go for <limits>

Support only standard and extended integral types (ruling out bool, wchar, etc).
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For the non-in_place functions, add a template parameter specifying a final conversion (specifying where the result will be stored).
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Forward to LWG for C++23 (with a TR).
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