allowing capital B in binary literals; see #2021; thanks @BrendanEich

lib/coffee-script/lexer.js

@@ -113,7 +113,7 @@
       if (!(match = NUMBER.exec(this.chunk))) return 0;
       number = match[0];
       lexedLength = number.length;
-      if (binaryLiteral = /0b([01]+)/.exec(number)) {
+      if (binaryLiteral = /0b([01]+)/i.exec(number)) {
         number = (parseInt(binaryLiteral[1], 2)).toString();
       }
       this.token('NUMBER', number);

src/lexer.coffee

@@ -134,7 +134,7 @@ exports.Lexer = class Lexer
     return 0 unless match = NUMBER.exec @chunk
     number = match[0]
     lexedLength = number.length
-    if binaryLiteral = /0b([01]+)/.exec number
+    if binaryLiteral = /0b([01]+)/i.exec number
       number = (parseInt binaryLiteral[1], 2).toString()
     @token 'NUMBER', number
     lexedLength

test/numbers.coffee

@@ -15,6 +15,7 @@
 
 test "Parser recognises binary numbers", ->
   eq 4, 0b100
+  eq 5, 0B101
 
 # Decimal Integer Literals