🚀 go-pugleaf

In a different topic, I'm confused about the different purpose ascribed to
exceptions derived from logic_error:

	"The class logic_error defines the type of objects thrown as exceptions
	to report errors presumably *detectable before the program executes*,
	such as violations of logical preconditions or invariants."

and runtime_error:

	"The class runtime_error defines the type of objects thrown as
	exceptions to report errors presumably only detectable when the program
	executes." 

It seems to me that with this wording most exceptions should be derived from
runtime_error. 
However, basic_string<...>::remove(size_type pos = 0, size_type n = npos),
for example, throws out_of_range (derived from logic error).

Unless the program only runs with manifest constants, it can't detect this
problem before the program executs:
	cin >> pos; mystring.remove(pos);

So why does it throw a logic_error rather than a runtime_error? Thanks!

(I'm also interested in learning whether it's a good idea to derive our
exceptions from standard exceptions).

Brian
-- 
        Brian Glendenning - National Radio Astronomy Observatory
bglenden@nrao.edu              Socorro NM               (505) 835-7347
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