Several small cleanups.
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c.texi
24
c.texi
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@ -2776,7 +2776,7 @@ again @samp{4}.
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Using @samp{++} or @samp{--} @emph{after} an lvalue does something
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peculiar: it gets the value directly out of the lvalue and @emph{then}
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increments or decrement it. Thus, the value of @code{i++} is the same
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increments or decrements it. Thus, the value of @code{i++} is the same
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as the value of @code{i}, but @code{i++} also increments @code{i} ``a
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little later.'' This is called @dfn{postincrement} or
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@dfn{postdecrement}.
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@ -2999,10 +2999,10 @@ if (r && x % r == 0)
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@end example
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@noindent
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A truth value is simply a number, so @code{r}
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as a truth value tests whether it is nonzero.
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But @code{r}'s meaning is not a truth value---it is a number to divide by.
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So it is better style to write the explicit @code{!= 0}.
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A truth value is simply a number, so using @code{r} as a truth value
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tests whether it is nonzero. But @code{r}'s meaning as en expression
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is not a truth value---it is a number to divide by. So it is better
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style to write the explicit @code{!= 0}.
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Here's another equivalent way to write it:
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@ -3021,7 +3021,7 @@ There are cases where assignments nested inside the condition can
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actually make a program @emph{easier} to read. Here is an example
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using a hypothetical type @code{list} which represents a list; it
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tests whether the list has at least two links, using hypothetical
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functions, @code{nonempty} which is true of the argument is a nonempty
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functions, @code{nonempty} which is true if the argument is a nonempty
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list, and @code{list_next} which advances from one list link to the
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next. We assume that a list is never a null pointer, so that the
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assignment expressions are always ``true.''
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@ -3035,8 +3035,8 @@ if (nonempty (list)
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@end example
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@noindent
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Here we get the benefit of the @samp{&&} operator, to avoid executing
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the rest of the code if a call to @code{nonempty} says ``false.'' The
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Here we take advantage of the @samp{&&} operator to avoid executing
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the rest of the code if a call to @code{nonempty} returns ``false.'' The
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only natural place to put the assignments is among those calls.
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It would be possible to rewrite this as several statements, but that
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@ -3071,7 +3071,7 @@ to compute and get the value from. It looks like this:
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@end menu
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@node Conditional Rules
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@subsection Rules for Conditional Operator
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@subsection Rules for the Conditional Operator
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The first operand, @var{condition}, should be a value that can be
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compared with zero---a number or a pointer. If it is true (nonzero),
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@ -3147,7 +3147,7 @@ next_element () ? : default_pointer
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@noindent
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is a way to advance the pointer and use its new value if it isn't
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null, but use @code{default_pointer} if that is null. We must not do
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null, but use @code{default_pointer} if that is null. We cannot do
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it this way,
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@example
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@ -3155,7 +3155,7 @@ next_element () ? next_element () : default_pointer
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@end example
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@noindent
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because it would advance the pointer a second time.
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because that would advance the pointer a second time.
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@node Comma Operator
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@section Comma Operator
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@ -3243,7 +3243,7 @@ which uses the comma operator and passes just one argument
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(with value 6).
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@strong{Warning:} don't use the comma operator around an argument
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of a function unless it helps understand the code. When you do so,
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of a function unless it makes the code more readable. When you do so,
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don't put part of another argument on the same line. Instead, add a
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line break to make the parentheses around the comma operator easier to
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see, like this.
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