From c4b72fcc794e235da11248a8a0f39624df5cf13a Mon Sep 17 00:00:00 2001
From: Michael Ficarra <git@michael.ficarra.me>
Date: Wed, 23 Mar 2011 13:49:15 -0400
Subject: [PATCH] improved range compilation

---
 lib/lexer.js     |  2 +-
 lib/nodes.js     | 13 ++++++-------
 src/nodes.coffee | 15 +++++++--------
 3 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/lib/lexer.js b/lib/lexer.js
index 945f11d7..8fdee451 100644
--- a/lib/lexer.js
+++ b/lib/lexer.js
@@ -459,7 +459,7 @@
     Lexer.prototype.balancedString = function(str, end) {
       var i, letter, prev, stack, _ref;
       stack = [end];
-      for (i = 1, _ref = str.length; (1 <= _ref ? i < _ref : i > _ref); (1 <= _ref ? i += 1 : i -= 1)) {
+      for (i = 1, _ref = str.length; 1 <= _ref ? i < _ref : i > _ref; 1 <= _ref ? i++ : i--) {
         switch (letter = str.charAt(i)) {
           case '\\':
             i++;
diff --git a/lib/nodes.js b/lib/nodes.js
index 7b2ccd5e..4a50faed 100644
--- a/lib/nodes.js
+++ b/lib/nodes.js
@@ -782,7 +782,7 @@
       }
     };
     Range.prototype.compileNode = function(o) {
-      var compare, idx, incr, intro, step, stepPart, vars;
+      var compare, cond, idx, incr, step, vars;
       this.compileVariables(o);
       if (!o.index) {
         return this.compileArray(o);
@@ -793,10 +793,9 @@
       idx = del(o, 'index');
       step = del(o, 'step');
       vars = ("" + idx + " = " + this.from) + (this.to !== this.toVar ? ", " + this.to : '');
-      intro = "(" + this.fromVar + " <= " + this.toVar + " ? " + idx;
-      compare = "" + intro + " <" + this.equals + " " + this.toVar + " : " + idx + " >" + this.equals + " " + this.toVar + ")";
-      stepPart = step ? step.compile(o) : '1';
-      incr = step ? "" + idx + " += " + stepPart : "" + intro + " += " + stepPart + " : " + idx + " -= " + stepPart + ")";
+      cond = "" + this.fromVar + " <= " + this.toVar;
+      compare = "" + cond + " ? " + idx + " <" + this.equals + " " + this.toVar + " : " + idx + " >" + this.equals + " " + this.toVar;
+      incr = step ? "" + idx + " += " + (step.compile(o)) : "" + cond + " ? " + idx + "++ : " + idx + "--";
       return "" + vars + "; " + compare + "; " + incr;
     };
     Range.prototype.compileSimple = function(o) {
@@ -816,7 +815,7 @@
       if (this.fromNum && this.toNum && Math.abs(this.fromNum - this.toNum) <= 20) {
         range = (function() {
           _results = [];
-          for (var _i = _ref = +this.fromNum, _ref2 = +this.toNum; _ref <= _ref2 ? _i <= _ref2 : _i >= _ref2; _ref <= _ref2 ? _i += 1 : _i -= 1){ _results.push(_i); }
+          for (var _i = _ref = +this.fromNum, _ref2 = +this.toNum; _ref <= _ref2 ? _i <= _ref2 : _i >= _ref2; _ref <= _ref2 ? _i++ : _i--){ _results.push(_i); }
           return _results;
         }).apply(this, arguments);
         if (this.exclusive) {
@@ -834,7 +833,7 @@
       } else {
         vars = ("" + i + " = " + this.from) + (this.to !== this.toVar ? ", " + this.to : '');
         clause = "" + this.fromVar + " <= " + this.toVar + " ?";
-        body = "var " + vars + "; " + clause + " " + i + " <" + this.equals + " " + this.toVar + " : " + i + " >" + this.equals + " " + this.toVar + "; " + clause + " " + i + " += 1 : " + i + " -= 1";
+        body = "var " + vars + "; " + clause + " " + i + " <" + this.equals + " " + this.toVar + " : " + i + " >" + this.equals + " " + this.toVar + "; " + clause + " " + i + "++ : " + i + "--";
       }
       post = "{ " + result + ".push(" + i + "); }\n" + idt + "return " + result + ";\n" + o.indent;
       return "(function() {" + pre + "\n" + idt + "for (" + body + ")" + post + "}).apply(this, arguments)";
diff --git a/src/nodes.coffee b/src/nodes.coffee
index 99370609..c139d23c 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -642,10 +642,9 @@ exports.Range = class Range extends Base
     idx      = del o, 'index'
     step     = del o, 'step'
     vars     = "#{idx} = #{@from}" + if @to isnt @toVar then ", #{@to}" else ''
-    intro    = "(#{@fromVar} <= #{@toVar} ? #{idx}"
-    compare  = "#{intro} <#{@equals} #{@toVar} : #{idx} >#{@equals} #{@toVar})"
-    stepPart = if step then step.compile(o) else '1'
-    incr     = if step then "#{idx} += #{stepPart}" else "#{intro} += #{stepPart} : #{idx} -= #{stepPart})"
+    cond     = "#{@fromVar} <= #{@toVar}"
+    compare  = "#{cond} ? #{idx} <#{@equals} #{@toVar} : #{idx} >#{@equals} #{@toVar}"
+    incr     = if step then "#{idx} += #{step.compile(o)}" else "#{cond} ? #{idx}++ : #{idx}--"
     "#{vars}; #{compare}; #{incr}"
 
   # Compile a simple range comprehension, with integers.
@@ -671,11 +670,11 @@ exports.Range = class Range extends Base
     pre    = "\n#{idt}#{result} = [];"
     if @fromNum and @toNum
       o.index = i
-      body = @compileSimple o
+      body    = @compileSimple o
     else
-      vars = "#{i} = #{@from}" + if @to isnt @toVar then ", #{@to}" else ''
-      clause = "#{@fromVar} <= #{@toVar} ?"
-      body   = "var #{vars}; #{clause} #{i} <#{@equals} #{@toVar} : #{i} >#{@equals} #{@toVar}; #{clause} #{i} += 1 : #{i} -= 1"
+      vars    = "#{i} = #{@from}" + if @to isnt @toVar then ", #{@to}" else ''
+      cond    = "#{@fromVar} <= #{@toVar}"
+      body    = "var #{vars}; #{cond} ? #{i} <#{@equals} #{@toVar} : #{i} >#{@equals} #{@toVar}; #{cond} ? #{i}++ : #{i}--"
     post   = "{ #{result}.push(#{i}); }\n#{idt}return #{result};\n#{o.indent}"
     "(function() {#{pre}\n#{idt}for (#{body})#{post}}).apply(this, arguments)"