From a4249fd5738cc37187f177be490d92171527864d Mon Sep 17 00:00:00 2001
From: charliesome <charlie@charliesomerville.com>
Date: Wed, 11 Jan 2012 17:14:23 +1100
Subject: [PATCH 1/2] power operator + tests

---
 src/grammar.coffee    | 2 ++
 src/lexer.coffee      | 1 +
 src/nodes.coffee      | 6 ++++++
 test/operators.coffee | 9 +++++++++
 4 files changed, 18 insertions(+)

diff --git a/src/grammar.coffee b/src/grammar.coffee
index 91ab43c5..7ad4fdd6 100644
--- a/src/grammar.coffee
+++ b/src/grammar.coffee
@@ -526,6 +526,7 @@ grammar =
     o 'Expression -  Expression',               -> new Op '-' , $1, $3
 
     o 'Expression MATH     Expression',         -> new Op $2, $1, $3
+    o 'Expression **       Expression',         -> new Op $2, $1, $3
     o 'Expression SHIFT    Expression',         -> new Op $2, $1, $3
     o 'Expression COMPARE  Expression',         -> new Op $2, $1, $3
     o 'Expression LOGIC    Expression',         -> new Op $2, $1, $3
@@ -560,6 +561,7 @@ operators = [
   ['nonassoc',  '++', '--']
   ['left',      '?']
   ['right',     'UNARY']
+  ['right',     '**']
   ['left',      'MATH']
   ['left',      '+', '-']
   ['left',      'SHIFT']
diff --git a/src/lexer.coffee b/src/lexer.coffee
index 050b3ce1..670edaee 100644
--- a/src/lexer.coffee
+++ b/src/lexer.coffee
@@ -599,6 +599,7 @@ OPERATOR   = /// ^ (
    | ([&|<>])\2=?      # logic / shift
    | \?\.              # soak access
    | \.{2,3}           # range or splat
+   | \*\*              # power
 ) ///
 
 WHITESPACE = /^[^\n\S]+/
diff --git a/src/nodes.coffee b/src/nodes.coffee
index 414f9130..0d3b23a5 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -1406,6 +1406,7 @@ exports.Op = class Op extends Base
     return @compileUnary     o if @isUnary()
     return @compileChain     o if isChain
     return @compileExistence o if @operator is '?'
+    return @compilePower     o if @operator is '**'
     code = @first.compile(o, LEVEL_OP) + ' ' + @operator + ' ' +
            @second.compile(o, LEVEL_OP)
     if o.level <= LEVEL_OP then code else "(#{code})"
@@ -1441,6 +1442,11 @@ exports.Op = class Op extends Base
     parts.push @first.compile o, LEVEL_OP
     parts.reverse() if @flip
     parts.join ''
+  
+  compilePower: (o) ->
+    left = @first.compile o, LEVEL_OP
+    right = @second.compile o, LEVEL_OP
+    "Math.pow(#{left}, #{right})"
 
   toString: (idt) ->
     super idt, @constructor.name + ' ' + @operator
diff --git a/test/operators.coffee b/test/operators.coffee
index 2ae0c6a9..c377410a 100644
--- a/test/operators.coffee
+++ b/test/operators.coffee
@@ -269,3 +269,12 @@ test "Regression with implicit calls against an indented assignment", ->
     1
 
   eq a, 1
+
+test "power operator", ->
+  eq 27, 3 ** 3
+
+test "power operator has higher precedence than other maths operators", ->
+  eq 55, 1 + 3 ** 3 * 2
+
+test "power operator is right associative", ->
+  eq 1, 1 ** 2 ** 3
\ No newline at end of file

From 3bd4dea3054ceb23476a6a743c1f4ef2206caea3 Mon Sep 17 00:00:00 2001
From: charliesome <charlie@charliesomerville.com>
Date: Wed, 11 Jan 2012 21:37:06 +1100
Subject: [PATCH 2/2] fix the precedence test so it's actually meaningful

---
 test/operators.coffee | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/operators.coffee b/test/operators.coffee
index c377410a..716b104a 100644
--- a/test/operators.coffee
+++ b/test/operators.coffee
@@ -277,4 +277,4 @@ test "power operator has higher precedence than other maths operators", ->
   eq 55, 1 + 3 ** 3 * 2
 
 test "power operator is right associative", ->
-  eq 1, 1 ** 2 ** 3
\ No newline at end of file
+  eq 2, 2 ** 1 ** 3
\ No newline at end of file