Fix termination node. Distinction between a variable const and a digi…

…t cause term(-1) to be incorrectly interpreted.

FINE := -1
.term(FINE)
interprets fine, but
.term(-1)
wasn't working.

lib/tp_plus/nodes/termination_node.rb

@@ -18,7 +18,12 @@ def eval(context)
 
         case @valuex
         when DigitNode
-          s += "#{@valuex.eval(context)}"
+          val = @valuex.eval(context)
+          if val[0] == "(" # negative
+            s = "FINE"
+          else
+            s += "#{val}"
+          end
         when VarNode
           if @valuex.constant?
             val = @valuex.eval(context)

test/tp_plus/test_interpreter.rb

@@ -1900,7 +1900,8 @@ def test_motion_arc
     arc_move.to(p3).at(200, 'mm/s').term(100)
     arc_move.to(p4).at(200, 'mm/s').term(100)
     arc_move.to(p5).at(200, 'mm/s').term(FINE)
-    linear_move.to(p6).at(200, 'mm/s').term(FINE)")
+    linear_move.to(p6).at(200, 'mm/s').term(FINE)
+    linear_move.to(p6).at(200, 'mm/s').term(-1)")
 
     assert_prog " ;\n" +
     " ;\n" +
@@ -1909,6 +1910,7 @@ def test_motion_arc
     "A P[3:p3] 200mm/sec CNT100 ;\n" +
     "A P[4:p4] 200mm/sec CNT100 ;\n" +
     "A P[5:p5] 200mm/sec FINE ;\n" +
+    "L P[6:p6] 200mm/sec FINE ;\n" +
     "L P[6:p6] 200mm/sec FINE ;\n"
   end