predicate function

[Lindley]

Lindley, under which circumstances does remove_if() take a binary predicate?
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BTW, how does your first example work at all, as I don't see an operator() in there anywhere? Is there a third way to define predicates I don't know of yet?

You're right, I goofed on the operator. And remove_if is not a good example of this predicate (perhaps std::sort would be better).