fixes #141; lexer: overhauled range expansion

lib/lexer.js

@@ -1227,7 +1227,7 @@ function addImplicitBraces(tokens){
   }
 }
 function expandLiterals(tokens){
-  var i, token, sig, lno, from, char, to, tochar, by, ts, n, word, that, __ref, __step, __i, __len;
+  var i, token, sig, lno, from, char, to, tochar, by, byp, ts, n, word, that, __ref, __i, __len;
   i = 0;
   while (token = tokens[++i]) {
     switch (token[0]) {
@@ -1244,16 +1244,22 @@ function expandLiterals(tokens){
       __ref = decode(token[1], lno = token[2]), from = __ref[0], char = __ref[1];
       __ref = decode(tokens[i + 1][1], lno), to = __ref[0], tochar = __ref[1];
       if (char ^ tochar) {
-        carp('bad "to" in range');
+        carp('bad "to" in range', lno);
       }
-      if (by = ((__ref = tokens[i + 2]) != null ? __ref[0] : void 8) === 'RANGE_BY') {
-        if (isNaN(by = (__ref = tokens[i + 3]) != null ? __ref[1] : void 8)) {
-          carp('bad "by" in range');
+      by = 1;
+      if (byp = ((__ref = tokens[i + 2]) != null ? __ref[0] : void 8) === 'RANGE_BY') {
+        if (!(by = +((__ref = tokens[i + 3]) != null ? __ref[1] : void 8))) {
+          carp('bad "by" in range', tokens[i + 2][2]);
+        }
+      }
+      if (token.op === 'til') {
+        to -= by / 2;
+        if (from > to ^ by < 0) {
+          to = from;
         }
       }
       ts = [];
-      to -= token.op === 'til' && 1e-15;
-      for (n = from, __step = +by || 1; __step < 0 ? n >= to : n <= to; n += __step) {
+      for (n = from; by < 0 ? n >= to : n <= to; n += by) {
         if (0x10000 < ts.push([
           'STRNUM', char
             ? character(n)
@@ -1263,7 +1269,7 @@ function expandLiterals(tokens){
         }
       }
       ts.pop() || carp('empty range', lno);
-      tokens.splice.apply(tokens, [i, by ? 4 : 2].concat(__slice.call(ts)));
+      tokens.splice.apply(tokens, [i, 2 + 2 * byp].concat(__slice.call(ts)));
       i += ts.length - 1;
       break;
     case 'WORDS':

src/lexer.co

@@ -827,17 +827,21 @@ character = if JSON!? then uxxxx else ->
         tokens.splice i++ 0 [\+- sig, token.2]
       continue if token.callable
     case \RANGE
-      [from, char] = decode token.1, lno = token.2
+      [from, char] = decode token.     1, lno = token.2
       [to, tochar] = decode tokens[i+1]1, lno
-      carp 'bad "to" in range' if char ^ tochar
-      if by = tokens[i+2]?0 is \RANGE_BY
-        carp 'bad "by" in range' if isNaN by = tokens[i+3]?1
-      ts = []; to -= token.op is \til and 1e-15
-      for n from from to to by +by or 1
+      carp 'bad "to" in range' lno if char ^ tochar
+      by = 1
+      if byp = tokens[i+2]?0 is \RANGE_BY
+        carp 'bad "by" in range' tokens[i+2]2 unless by = +tokens[i+3]?1
+      if token.op is \til
+        to -= by / 2
+        to = from if from > to ^ by < 0
+      ts = []
+      for n from from to to by by
         carp 'range limit exceeded' lno if 0x10000 < ts.push \
           [\STRNUM, if char then character n else "#n", lno] [\, \, lno]
       ts.pop! or carp 'empty range' lno
-      tokens.splice i, if by then 4 else 2, ...ts
+      tokens.splice i, 2 + 2 * byp, ...ts
       i += ts.length - 1
     case \WORDS
       ts = [[\[ \[ lno = token.2]]

test/literal.co

@@ -20,16 +20,6 @@ eq 36, 0XF + 36RT
 eq 100m2, 10m ** 2
 eq 3000c, 30$ * 100
 
-# [#31](https://github.com/satyr/coco/issues/31): Numeric Ranges
-eq '1,2,3'  String [1 to +3]
-eq '1,0,-1' String Array 1 to -1 by -1
-
-til = String
-eq 2, [Number]0 til 2
-
-throws 'range limit exceeded on line 1' -> Coco.tokens '0 to 1 by 1e-5'
-throws 'empty range on line 3'          -> Coco.tokens '\n\n 1 to 0'
-
 # [coffee#764](https://github.com/jashkenas/coffee-script/issues/764)
 # Boolean/Number should be indexable.
 ok 42['toString']
@@ -419,5 +409,33 @@ eq o.3, 3
 eq o.5, 5
 
 
+### Numeric/Character Ranges
+show = -> @@ * ' '
+
+eq '-1 0 1 2' show -1 to +2
+eq '1 0 -1'   show +1 to -1 by -1
+
+eq '999 1000' show 999     til 1001
+eq '1e-9'     show 1e-9    til 1e-8
+eq '9999999'  show 9999999 til 1e7
+eq '10000000' show 1e7     til 9999999 by -1
+
+eq '0.5 0.75 1' show 0.5 til 1.2 by 0.25
+
+til = String
+eq 2, [Number]0 til 2
+
+eq 'A F K P U Z' show \A to  \Z by 5
+eq 'y u q m i e' show \y til \a by -4
+
+ok \\u2028 to \\u2029
+
+throws 'range limit exceeded on line 2' -> Coco.tokens '\n0 to 1 by 1e-5'
+throws 'empty range on line 2'          -> Coco.tokens '\n1 to 0'
+throws 'bad "to" in range on line 2'    -> Coco.tokens '\n0 to "q"'
+throws 'bad "by" in range on line 2'    -> Coco.tokens '\n0 to 9 by "2"'
+throws 'bad string in range on line 2'  -> Coco.tokens '\n"a" to "bc"'
+
+
 ### Misc
 throws \unimplemented -> ...

test/string.co

@@ -205,14 +205,6 @@ eq('+', \+)
 eq '\\', [\\\].0
 eq '$', {\$}.\$
 
-eq 'AFKPUZ' [\A to \Z by 5]*''
-
-throws 'bad "to" in range on line 1'   -> Coco.tokens '0 to "q"'
-throws 'bad "by" in range on line 1'   -> Coco.tokens '0 to 9 by "2"'
-throws 'bad string in range on line 1' -> Coco.tokens '"a" to "bc"'
-
-ok \\u2028 to \\u2029
-
 
 # [coffee#923](https://github.com/jashkenas/coffee-script/issues/923)
 eq "#{ "{" }", "{"