#3191 parsing problem: thru 3 for i in [a,b]

[Stavros Macrakis]

thru 3 for i in [2,4] do print(i);
parses as
((MDOIN SIMP) $I ((MLIST SIMP) 2 4) NIL NIL 3 NIL (($PRINT SIMP) $I))
which prints as
for i in [2,3,4] thru 3 do print(i);

When executed, it prints 2 and 3

It is apparently equivalent to
for i in [2,3,4] while i<=3 do print(i)
or
while i<=3 for i in [2,3,4] do print(i)

On the other hand,
for i in [2,4] thru 3 do print(i)
says "A do cannot have a thru with a [sic] in field"

The first version should cause the same parse error.

Maxima branch_5_37_base_528_g802ae7f on SBCL 1.2.11

[Kris Katterjohn]

diff --git a/src/nparse.lisp b/src/nparse.lisp
index b32a03fd4..c2de06e0a 100644
--- a/src/nparse.lisp
+++ b/src/nparse.lisp
@@ -1558,7 +1558,7 @@
   ($do    . ())
   ($for    . ($for))
   ($from   . ($in $from))
-  ($in     . ($in $from $step $next))
+  ($in     . ($in $from $step $next $thru))
   ($step   . ($in       $step $next))
   ($next   . ($in  $step $next))
   ($thru   . ($in $thru)) ;$IN didn't used to get checked for

No problems with the test suite, share test suite or rtest_translator.

Before:

(%i1) '(thru 3 for i in [1, 2, 3, 4] do print (i));
(%o1) for i in [1,2,3,4] thru 3 do print(i)

(%i2) thru 3 for i in [1, 2, 3, 4] do print (i);

1
2
3
(%o2) done

(%i3) '(for i in [1, 2, 3, 4] thru 3 do print (i));

incorrect syntax: A do cannot have a thru with a in field.
n [1, 2, 3, 4] thru
                  ^

After:

(%i4) '(thru 3 for i in [1, 2, 3, 4] do print (i));

incorrect syntax: A do cannot have a in with a thru field.
'(thru 3 for i in
                ^
(%i4) '(for i in [1, 2, 3, 4] thru 3 do print (i));

incorrect syntax: A do cannot have a thru with a in field.
n [1, 2, 3, 4] thru
                  ^

[Kris Katterjohn]

Fixed by commit [f2a4dd].