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+======Synopsis:======
+[[for]] (//once//, //expression//, //each//) { //[[block]]// } \\
+[[for]] //var// from //firstval// to //lastval// { //[[block]]// } \\
+[[for]] //var// from //firstval// to //lastval// step //stepval// { //[[block]]// } \\
+[[for]] //var// in (//word list//) { //[[block]]// }
+======Description (standard form):======
+[[FOR]] is a general purpose loop.  It is modeled on the C for statement,
+and works in a very similar manner.  Aside from the action, there are
+three parts to a [[FOR]] loop:
+The //once// part is a //[[block]]// executed before the loop begins
+iterating.  This is often used for initializing counters and other
+variables that will be used in the loop.
+Before each loop iteration, the //condition// expression is checked.
+Most often, this is used to see if the counter has exceeded a certain limit.
+The condition may contain any expression legal in the [[IF]] command.
+Because of this, the loop does not necessarily have to iterate at all.
+The //each// part is a //[[block]]// executed each time the loop exits and
+before the //condition// is tested.  This is where you would increment a
+counter that gets checked by the condition statement.
+It is imperative to note that the three sections are separated by commas
+and not semicolons; this is because //once// and //each// may contain
+semicolons if they contain multiple statements.  This is the reverse of C.
+The first and third section are **COMMANDS** and the second section is an
+**EXPRESSION**.
+//Once//, //each//, and //block// are optional and may be left blank.
+======Description (for/next form):======
+This second form of the command provides a FOR .. NEXT type loop that
+enumerates each of the integers between //firstval// and //lastval//.
+Each enumerated integer is assigned to //var// and the //block// is
+executed.
+If you wish enumerate only some of the values in the range, you can
+specify a //step//, which says that each //step//th value should be
+enumerated.
+If //firstval// is greater than //lastval// then you must specify a
+//step// value and it must be negative.  If you do not do this, then
+the loop will not execute.
+The //var// variable should be considered read-only.  Changing it will
+**not** affect how the range is enumerated.
+This form is much cheaper than a standard [[for]], and is cheaper than a [[fe]]
+over a [[jot]] range.
+The [[CONTINUE]] and [[BREAK]] commands are honored in the action body.
+The [[CONTINUE]] command will behave as a "next" operation, and the [[BREAK]]
+command will abort the loop entirely.
+======Description (for/each form):======
+This third and final form is a FOR .. IN LIST type loop that iterates over
+each word in the word list, assiging each value in turn to the //var// and
+executing the //block//.
+This form is cheaper than [[fe]] because it is optimized for iterating
+one word at a time, whereas [[fe]] is general-purpose.
+The [[CONTINUE]] and [[BREAK]] commands are also honored in the same way
+as in the second form above.
+======Examples:======
+Form 1:
+To display a warning message 3 times:
+      for ( @ xx = 3, xx > 0, @ xx-- ) {
+         echo WARNING!  This ship will self destruct in $xx seconds!
+      }
+A infinite loop that behaves like the Unix 'yes' command:
+      for ( ,, ) {
+         echo yes
+      }
+Form 2:
+Display the numbers 1 through 5 each on a separate line:
+      for ii from 1 to 5 {
+         echo $ii
+      }
+Display the numbers 1, 3, and 5 each on a separate line:
+      for ii from 1 to 5 step 2 {
+         echo $ii
+      }
+Form 3:
+Display the words "one", "two", and "three" each on a separate line:
+      for xx in (one two three) {
+         echo $xx
+      }
+======History:======