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1.0 KiB
[linalg.helpers.abs]
29 Numerics library [numerics]
29.9 Basic linear algebra algorithms [linalg]
29.9.7 Exposition-only helpers [linalg.helpers]
29.9.7.1 abs-if-needed [linalg.helpers.abs]
The name abs-if-needed denotes an exposition-only function object.
The expression abs-if-needed(E) for a subexpression E whose type is T is expression-equivalent to:
E if T is an unsigned integer;
otherwise, std::abs(E) if T is an arithmetic type,
otherwise, abs(E), if that expression is valid, with overload resolution performed in a context that includes the declarationtemplate U abs(U) = delete; If the function selected by overload resolution does not return the absolute value of its input, the program is ill-formed, no diagnostic required.