Replace 'step' with 'by' in for loops, fixes #1704

xlr/include/basics.tbl

@@ -492,7 +492,8 @@ INFIX(TextAt, text, text, "at", integer,
       SYNOPSIS("")
       DESCRIPTION("")
       RETURNS(text, ""))
-INFIX(ListIndex, tree, tree, "at", tree, return xl_index(context, &l, &r), )
+INFIX(ListIndex, tree, tree, "at", tree,
+      return xl_array_index(context, &l, &r), )
 
 // Some other text primitives
 PREFIX(TextLength, integer, "text_length",
@@ -878,7 +879,7 @@ FORM(IntegerForLoop, tree,
      PARM(Body, source, ""),
      return xl_integer_for_loop(context,self, &Var, Low, High, 1, &Body), )
 FORM(IntegerForLoopStep, tree,
-     "for Var in Low:integer..High:integer step Step:integer loop Body",
+     "for Var in Low:integer..High:integer by Step:integer loop Body",
      PARM(Var, tree, "")
      PARM(Low, integer, "")
      PARM(High, integer, "")
@@ -893,7 +894,7 @@ FORM(RealForLoop, tree,
      PARM(Body, source, ""),
      return xl_real_for_loop(context,self, &Var, Low, High, 1.0, &Body), )
 FORM(RealForLoopStep, tree,
-     "for Var in Low:real..High:real step Step:real loop Body",
+     "for Var in Low:real..High:real by Step:real loop Body",
      PARM(Var, tree, "")
      PARM(Low, real, "")
      PARM(High, real, "")

xlr/tests/05.Control/loops.xl

@@ -16,8 +16,8 @@ for I in 1..9 loop
     writeln
 
 writeln "Step loop"
-for I in 1..9 step 2 loop
-    for J in 1..9 step 3 loop
+for I in 1..9 by 2 loop
+    for J in 1..9 by 3 loop
         write "[", I, ",", J, "]"
     writeln
 
@@ -31,21 +31,21 @@ for A in 0.3..9.1 loop
     writeln
 
 writeln "Step real loop"
-for A in 0.1..2.9 step 1.3 loop
-    for B in 0.3..9.1 step 3.1 loop
+for A in 0.1..2.9 by 1.3 loop
+    for B in 0.3..9.1 by 3.1 loop
         write "[", A, ",", B, "]"
     writeln
 
 
 writeln "Step loop backwards"
-for I in 9..1 step -2 loop
-    for J in 9..1 step -3 loop
+for I in 9..1 by -2 loop
+    for J in 9..1 by -3 loop
         write "[", I, ",", J, "]"
     writeln
 
 writeln "Step real loop backwards"
-for A in 5.1..3.3 step -0.3 loop
-    for B in 9.4..9.1 step -0.1 loop
+for A in 5.1..3.3 by -0.3 loop
+    for B in 9.4..9.1 by -0.1 loop
         write "[", A, ",", B, "]"
     writeln
 

xlr/xl.syntax

@@ -6,7 +6,7 @@ INFIX
         50      then require ensure
         61      ;
         75      with
-        85     := += -= *= /= ^= |= &=
+        85      := += -= *= /= ^= |= &=
         100     STATEMENT
         110     is as 
         120     written
@@ -18,7 +18,7 @@ INFIX
         250     and or xor
         260     in at contains
         271     of to
-        280     .. step
+        280     .. by
         290     = < > <= >= <>
         300     & |
         310     + -