fix guide typos

svn: r10862

collects/scribblings/guide/begin.scrbl

@@ -43,7 +43,7 @@ sometimes said to have an @defterm{implicit begin}.
 @defexamples[
 (define (print-triangle height)
   (cond
-    [(not (positive? height))
+    [(positive? height)
      (display (make-string height #\*))
      (newline)
      (print-triangle (sub1 height))]))

collects/scribblings/guide/case.scrbl

@@ -15,7 +15,7 @@ of an expression to the values for the clause:
 
 Each @scheme[_datum] will be compared to the result of the first
 @scheme[_expr] using @scheme[eqv?]. Since @scheme[eqv?] doesn't work on
-many kinds of values, notably symbols and lists, each @scheme[_datum]
+many kinds of values, notably strings and lists, each @scheme[_datum]
 is typically a number, symbol, or boolean.
 
 Multiple @scheme[_datum]s can be supplied for each clause, and the

collects/scribblings/guide/cond.scrbl

@@ -62,15 +62,15 @@ the answer.
 
 @specform[(and expr ...)]
 
-An @scheme[or] form produces @scheme[#f] if any of its @scheme[expr]s
+An @scheme[and] form produces @scheme[#f] if any of its @scheme[_expr]s
 produces @scheme[#f]. Otherwise, it produces the value of its last
 @scheme[_expr]. As a special case, @scheme[(and)] produces
 @scheme[#t].
 
 @specform[(or expr ...)]
 
-The @scheme[and] form produces @scheme[#f] if any of its
-@scheme[_expr]s produces @scheme[#f]. Otherwise, it produces the first
+The @scheme[or] form produces @scheme[#f] if all of its
+@scheme[_expr]s produce @scheme[#f]. Otherwise, it produces the first
 non-@scheme[#f] value from its @scheme[expr]s.  As a special case,
 @scheme[(or)] produces @scheme[#f].
 
@@ -87,7 +87,7 @@ non-@scheme[#f] value from its @scheme[expr]s.  As a special case,
 If evaluation reaches the last @scheme[_expr] of an @scheme[and] or
 @scheme[or] form, then the @scheme[_expr]'s value directly determines
 the @scheme[and] or @scheme[or] result. Therefore, the last
-@scheme[expr] is in tail position, which means that the above
+@scheme[_expr] is in tail position, which means that the above
 @scheme[got-milk?] function runs in constant space.
 
 @guideother{@secref["tail-recursion"] introduces tail calls and tail positions.}

collects/scribblings/guide/lists.scrbl

@@ -99,7 +99,7 @@ extra first argument. Also, a starting ``current'' value must be
 provided before the lists:
 
 @interaction[
-(foldl (lambda (v elem)
+(foldl (lambda (elem v)
          (+ v (* elem elem)))
        0
        '(1 2 3))