Compound Assignments

[kevin.laux]

In article <15823 at smoke.brl.mil>, gwyn at smoke.brl.mil (Doug Gwyn) writes:
> In article <1991Apr11.183942.2195 at mccc.edu> pjh at mccc.edu (Pete Holsberg) writes:
> >In article <15776 at smoke.brl.mil> gwyn at smoke.brl.mil (Doug Gwyn) writes:
> >=In article <1991Apr8.174951.22448 at mccc.edu> pjh at mccc.edu (Pete Holsberg) writes:
> >=>=	A compound assignment of the form E1 op= E2 differs from the
> >=>=	simple assignment expression E1 = E1 op (E2) only in that the
> >=>=	lvalue E1 is evaluated only once.

	[stuff about ambiguity and understanding deleted]

	I think the problem of 'ambiguity' arises from what expressions are
chosen as examples.

	For instance,		(E1 = x)

	x += y		and 	x = x + y

	produce the same result but might cause one to say E1 evaluated only
once?

	Whereas			(E1 = x [i++])

	x [i++] += y	and	x [i++] = x [i++] + y

	do not produce the same result but more clearly illustrates the point
that in compound assignments E1 is evaluated only once.

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